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Y Attafi - One of the best experts on this subject based on the ideXlab platform.
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oxygen broadening and shift coefficients in the ν6 band of Methyl Iodide 12ch3i at room temperature
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: Y Attafi, Ben A Hassen, H Aroui, Kwabia F Tchana, Laurent Manceron, Vander J Auwera, A Perrin, S Galalou, D DoiziAbstract:Abstract In this study we report the high-resolution measurements of oxygen pressure- broadening and pressure-induced shift coefficients for rovibrational transitions in the ν6 band of Methyl Iodide (12CH3I), centered at 892.918 cm–1. The results were obtained by analyzing fourteen high-resolution room temperature laboratory absorption spectra with a mono-spectrum non-linear least squares fitting of Voigt profiles. The data were recorded with the Bruker IF125HR Fourier transform spectrometer located at the LISA facility in Creteil, using a White type cell with a path length of 564.9 cm and total pressures up to 295 hPa. The measured oxygen-broadening coefficients range from 0.0648 to 0.1207 cm–1atm–1 at 295 K. The measured shift coefficients were all negative and varied between −0.00044 and −0.04984 cm–1atm–1. The average accuracy on the measured O2-broadening coefficients and pressure shift coefficients was estimated to about 4% and 11%, respectively. The O2-broadening coefficients obtained in the present work are compared with values reported in the literature for the ν5 band of CH3I, showing a satisfactory agreement with an average difference of about 8%. The shift coefficients are compared with values reported in the literature for the ν6 band of CH3F-Ar system, exhibiting the same order of magnitude and trend. The J and K rotational dependences of the O2-broadening coefficients have been observed and the latter modeled using empirical polynomial expansions. On average, the empirical expression reproduces the measured O2-broadening coefficients to within 3%. Using the measured broadening coefficients of the CH3I-O2 and CH3I-N2 [Attafi et al., J Quant Spectrosc Radiat Transf 231 (2019) 1–8] systems, we produced CH3I-air broadening coefficients, ranging from 0.0783 to 0.1385 cm–1atm–1 at 295 K. The present results and the data already available should be valuable not only for predicting the CH3I infrared spectrum in the atmosphere, but also for verifying theoretical calculations of pressure-broadening and pressure-shift coefficients in the ν6 region of Methyl Iodide spectra.
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self and n2 collisional broadening of rovibrational lines in the ν6 band of Methyl Iodide 12ch3i at room temperature the j and k dependence
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: Y Attafi, Ben A Hassen, H Aroui, Kwabia F Tchana, Laurent Manceron, D Doizi, Vander J Auwera, A PerrinAbstract:Abstract Following our recent study devoted to measurements of intensities of rovibrational lines in the ν6 band of Methyl Iodide (12CH3I) centered at 892.918 cm−1, room temperature infrared spectra of Methyl Iodide diluted in nitrogen at fourteen total pressures between 20 and 300 hPa have been recorded using the Fourier transform spectrometer Bruker IF125HR located at the LISA facility in Creteil. Three hundred and forty six N2-broadening coefficients of Methyl Iodide rovibrational lines have been measured in the 824–951 cm−1 spectral range using mono-spectrum non-linear least squares fitting of Voigt profiles. Pressure-induced line shifts were not needed to fit the spectra to the noise level and line mixing effects could be neglected. Six hundred and eight self-broadening coefficients have also been measured in the same spectral range using the pure Methyl Iodide spectra recorded in our previous work. The measured self-broadening coefficients range from 0.1460 to 0.3786 cm−1 atm−1 and the N2-broadening coefficients range from 0.0723 to 0.1481 cm−1 atm−1 at 295 K. The average accuracy on the measured self- and N2-broadening coefficients was estimated to 3%. Comparisons with measurements reported in the literature for the ν5 band of CH3I shows a satisfactory agreement with average differences of 7% and 4% for the self- and N2-broadening coefficients, respectively. The J and K rotational dependences of these coefficients have been observed and the latter modeled using an empirical polynomial expansion. On average, the empirical expression reproduces the measured self- and N2-broadening coefficients to within 3% and 4%, respectively. The data obtained in the present work represent a significant contribution to the determination of broadening coefficients of CH3I and complement the list of line positions and intensities generated in our previous work, thus providing useful spectroscopic information for atmospheric remote sensing and industrial detection of CH3I.
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line intensities for the ν6 and 2ν3 bands of Methyl Iodide 12ch3i
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: F Kwabiatchana, Y Attafi, Laurent Manceron, D Doizi, Vander J Auwera, A PerrinAbstract:Abstract The goal of this study is to measure for the first time absolute line intensities for the ν6 band of Methyl Iodide (CH3I) centered at 892.918 cm–1. High-resolution Fourier transform spectra were recorded at various pressures for the whole 500–1450 cm–1 spectral range. Using these spectra, a large set of CH3I individual line intensities was measured for the ν6 band. These experimental intensities were least squares fitted to derive the expansion of the ν6 transition moment operator. The theoretical model used to describe the line positions and intensities accounts for the hyperfine structure in the 61 and ground states and for the vibration-rotation resonances that couple the 61 energy levels with those of the 32 and 21 vibrational states [Perrin et al., J. Mol. Spectrosc. 324 (2016) 28–35]. As the 2ν3 band is extremely weak, its associated transition moment operator was estimated from band strength available in the literature. A comprehensive list of line positions and intensities was generated for the ν6 and 2ν3 bands of CH3I at 11 µm, which should be useful for the possible detection of this species by the future IASI-NG satellite instrument (Infrared Atmospheric Sounding Interferometer New Generation), now under preparation ( https://iasi-ng.cnes.fr/en/IASI-NG/index.htm ).
A Perrin - One of the best experts on this subject based on the ideXlab platform.
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oxygen broadening and shift coefficients in the ν6 band of Methyl Iodide 12ch3i at room temperature
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: Y Attafi, Ben A Hassen, H Aroui, Kwabia F Tchana, Laurent Manceron, Vander J Auwera, A Perrin, S Galalou, D DoiziAbstract:Abstract In this study we report the high-resolution measurements of oxygen pressure- broadening and pressure-induced shift coefficients for rovibrational transitions in the ν6 band of Methyl Iodide (12CH3I), centered at 892.918 cm–1. The results were obtained by analyzing fourteen high-resolution room temperature laboratory absorption spectra with a mono-spectrum non-linear least squares fitting of Voigt profiles. The data were recorded with the Bruker IF125HR Fourier transform spectrometer located at the LISA facility in Creteil, using a White type cell with a path length of 564.9 cm and total pressures up to 295 hPa. The measured oxygen-broadening coefficients range from 0.0648 to 0.1207 cm–1atm–1 at 295 K. The measured shift coefficients were all negative and varied between −0.00044 and −0.04984 cm–1atm–1. The average accuracy on the measured O2-broadening coefficients and pressure shift coefficients was estimated to about 4% and 11%, respectively. The O2-broadening coefficients obtained in the present work are compared with values reported in the literature for the ν5 band of CH3I, showing a satisfactory agreement with an average difference of about 8%. The shift coefficients are compared with values reported in the literature for the ν6 band of CH3F-Ar system, exhibiting the same order of magnitude and trend. The J and K rotational dependences of the O2-broadening coefficients have been observed and the latter modeled using empirical polynomial expansions. On average, the empirical expression reproduces the measured O2-broadening coefficients to within 3%. Using the measured broadening coefficients of the CH3I-O2 and CH3I-N2 [Attafi et al., J Quant Spectrosc Radiat Transf 231 (2019) 1–8] systems, we produced CH3I-air broadening coefficients, ranging from 0.0783 to 0.1385 cm–1atm–1 at 295 K. The present results and the data already available should be valuable not only for predicting the CH3I infrared spectrum in the atmosphere, but also for verifying theoretical calculations of pressure-broadening and pressure-shift coefficients in the ν6 region of Methyl Iodide spectra.
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self and n2 collisional broadening of rovibrational lines in the ν6 band of Methyl Iodide 12ch3i at room temperature the j and k dependence
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: Y Attafi, Ben A Hassen, H Aroui, Kwabia F Tchana, Laurent Manceron, D Doizi, Vander J Auwera, A PerrinAbstract:Abstract Following our recent study devoted to measurements of intensities of rovibrational lines in the ν6 band of Methyl Iodide (12CH3I) centered at 892.918 cm−1, room temperature infrared spectra of Methyl Iodide diluted in nitrogen at fourteen total pressures between 20 and 300 hPa have been recorded using the Fourier transform spectrometer Bruker IF125HR located at the LISA facility in Creteil. Three hundred and forty six N2-broadening coefficients of Methyl Iodide rovibrational lines have been measured in the 824–951 cm−1 spectral range using mono-spectrum non-linear least squares fitting of Voigt profiles. Pressure-induced line shifts were not needed to fit the spectra to the noise level and line mixing effects could be neglected. Six hundred and eight self-broadening coefficients have also been measured in the same spectral range using the pure Methyl Iodide spectra recorded in our previous work. The measured self-broadening coefficients range from 0.1460 to 0.3786 cm−1 atm−1 and the N2-broadening coefficients range from 0.0723 to 0.1481 cm−1 atm−1 at 295 K. The average accuracy on the measured self- and N2-broadening coefficients was estimated to 3%. Comparisons with measurements reported in the literature for the ν5 band of CH3I shows a satisfactory agreement with average differences of 7% and 4% for the self- and N2-broadening coefficients, respectively. The J and K rotational dependences of these coefficients have been observed and the latter modeled using an empirical polynomial expansion. On average, the empirical expression reproduces the measured self- and N2-broadening coefficients to within 3% and 4%, respectively. The data obtained in the present work represent a significant contribution to the determination of broadening coefficients of CH3I and complement the list of line positions and intensities generated in our previous work, thus providing useful spectroscopic information for atmospheric remote sensing and industrial detection of CH3I.
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line intensities for the ν6 and 2ν3 bands of Methyl Iodide 12ch3i
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: F Kwabiatchana, Y Attafi, Laurent Manceron, D Doizi, Vander J Auwera, A PerrinAbstract:Abstract The goal of this study is to measure for the first time absolute line intensities for the ν6 band of Methyl Iodide (CH3I) centered at 892.918 cm–1. High-resolution Fourier transform spectra were recorded at various pressures for the whole 500–1450 cm–1 spectral range. Using these spectra, a large set of CH3I individual line intensities was measured for the ν6 band. These experimental intensities were least squares fitted to derive the expansion of the ν6 transition moment operator. The theoretical model used to describe the line positions and intensities accounts for the hyperfine structure in the 61 and ground states and for the vibration-rotation resonances that couple the 61 energy levels with those of the 32 and 21 vibrational states [Perrin et al., J. Mol. Spectrosc. 324 (2016) 28–35]. As the 2ν3 band is extremely weak, its associated transition moment operator was estimated from band strength available in the literature. A comprehensive list of line positions and intensities was generated for the ν6 and 2ν3 bands of CH3I at 11 µm, which should be useful for the possible detection of this species by the future IASI-NG satellite instrument (Infrared Atmospheric Sounding Interferometer New Generation), now under preparation ( https://iasi-ng.cnes.fr/en/IASI-NG/index.htm ).
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new analysis of the ν 6 and 2ν 3 bands of Methyl Iodide ch 3 i
Journal of Molecular Spectroscopy, 2016Co-Authors: A Perrin, D Doizi, F Kwabiatchana, I Haykal, L Manceron, G DucrosAbstract:Abstract A new rovibrational study of the ν6 band of Methyl Iodide was conducted to obtain a rather complete line list. A new analysis of line positions was accomplished. The spectrum of this band has been first recorded using the Bruker IFS125HR Fourier transform spectrometer (FTS) at the AILES beamline of the SOLEIL Synchrotron facility and later with the Bruker IFS125HR FTS located at the LISA facility in Creteil. Altogether, about 10,000 lines were assigned for the ν6 and 2ν3 bands up to high quantum numbers (J ⩽ 85 and K ⩽ 20). Because of the large value of the 127I nuclear quadrupole hyperfine constant, a significant portion of these assignments concerns clusters of hyperfine subcomponents, which are easily observable at 11 μm. These infrared data were combined in a least squares fit together with the existing microwave data on rotational transitions within the v6 = 1 and v3 = 2 vibrational states to get the upper state rotational constants and interacting parameters for the v6 = 1 and v3 = 2 states. Due to the high values of quantum numbers achieved during this infrared analysis, the final energy level calculation accounts for aCx ( Δ l = ± 1 ; Δ K = ± 1 ) and an α ( Δ l = ∓ 1 ; Δ K = ± 2 ) types of Coriolis interactions coupling the v6 = 1 energy levels with those from the v3 = 2 and v2 = 1 states, respectively. On the other hand, it proved unnecessary to update the existing hyperfine parameters for the v6 = 1 and v3 = 2 states.
Masaaki Suzuki - One of the best experts on this subject based on the ideXlab platform.
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pd0 mediated rapid coupling between Methyl Iodide and heteroarylstannanes an efficient and general method for the incorporation of a positron emitting 11c radionuclide into heteroaromatic frameworks
Chemistry: A European Journal, 2009Co-Authors: Masaaki Suzuki, Takamitsu Hosoya, Kengo Sumi, Hiroko Koyama, Misato Takashimahirano, Hisashi DoiAbstract:The Pd(0)-mediated rapid trapping of Methyl Iodide with an excess amount of a heteroaryl-substituted tributylstannane has been investigated with the aim of incorporating a short-lived (11)C-labelled Methyl group into the heteroaromatic carbon frameworks of important organic compounds, such as drugs with various heteroaromatic structures, in order to execute a positron emission tomography (PET) study of vital systems. The reaction was first performed by using our previously developed CH(3)I/stannane/[Pd(2)(dba)(3)]/P(o-CH(3)C(6)H(4))(3)/CuCl/K(2)CO(3) (1:40:0.5:2:2:2) system in DMF at 60 degrees C for 5 min (conditions A), however, the reaction gave low yields for various heteroaromatic compounds. Increasing the amount of phosphine ligand (conditions B) led to a significant improvement in the yield, but the conditions were still not suitable for a range of basic heteroaromatic structures. Use of the CuBr/CsF system (conditions C) also provided a result similar to that obtained under conditions B with an increased amount of the phosphine. Thus, pyridine and related heteroaromatic compounds remained less reactive substrates. The problem was overcome by replacing the DMF solvent with N-Methyl-2-pyrolidinone (NMP). The reaction in NMP at 60-100 degrees C for 5 min using a CH(3)I/stannane/[Pd(2)(dba)(3)]/P(o-CH(3)C(6)H(4))(3)/CuBr/CsF (1:40:0.5:16:2:5) combination (conditions D) gave the Methylated products in yields of more than 80 % (based on the reaction of CH(3)I) for all of the heteroaromatic compounds listed in this study. Thus, the combined use of NMP and an increased amount of phosphine is important for promoting the reaction efficiently. The use of this general approach to rapid Methylation has been well demonstrated by the synthesis of the PET tracers 2- and 3-[(11)C]Methylpyridines by using [Pd(2)(dba)(3)]/P(o-CH(3)C(6)H(4))(3)/CuBr/CsF (1:16:2:5) in NMP at 60 degrees C for 5 min, which gives the desired products in HPLC analytical yields of 88 and 91 %, respectively.
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rapid Methylation on carbon frameworks useful for the synthesis of 11ch3 incorporated pet tracers pd 0 mediated rapid coupling of Methyl Iodide with an alkenyltributylstannane leading to a 1 Methylalkene
ChemInform, 2006Co-Authors: Takamitsu Hosoya, Hisashi Doi, Masahiro Wakao, Kengo Sumi, Masaaki SuzukiAbstract:The Pd(0)-mediated rapid coupling of Methyl Iodide with an excess of alkenyltributylstannane was examined with the aim of incorporating a short-lived 11C-labeled Methyl group into a biologically significant organic compound with a 1-Methylalkene unit for the synthesis of a PET tracer. Four sets of reaction conditions (A–D) were used, all performed in DMF at 60 °C for 5 min. Condition B, using CH3I/stannane/Pd2(dba)3/P(o-tolyl)3/CuCl/K2CO3 (1 : 40 : 0.5 : 4–6 : 2 : 5), works well in almost all cases. Condition D, using CH3I/stannane/Pd2(dba)3/P(o-tolyl)3/CuX (X = Br, Cl, or I)/CsF (1 : 40 : 0.5–5 : 2–20 : 2–20 : 5–50), shows the best results with regard to general applicability to tin substrates, affording the corresponding Methylated product in >90% yield based on consumption of Methyl Iodide. P(t-Bu)2Me was less effective than P(o-tolyl)3, particularly for α,β-unsaturated carbonyl substrates. No regio- or stereoisomerization occurred under these reaction conditions. The efficiency of the protocol was demonstrated by synthesis of an 11C-Methylated compound.
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rapid Methylation of terminal acetylenes by the stille coupling of Methyl Iodide with alkynyltributylstannanes a general protocol potentially useful for the synthesis of short lived 11ch3 labeled pet tracers with a 1 propynyl group
ChemInform, 2004Co-Authors: Takamitsu Hosoya, Hisashi Doi, Masahiro Wakao, Yurie Kondo, Masaaki SuzukiAbstract:The Pd(0)-mediated rapid coupling (trapping) reaction of Methyl Iodide with an excess amount of alkynyltributylstannane has been developed with the aim to incorporate a short-lived 11C-labeled Methyl group into biologically active organic compounds with a 1-propynyl structural unit.
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synthesis of a 11c labelled prostaglandin f2α analogue using an improved method for stille reactions with 11c Methyl Iodide
Journal of Labelled Compounds and Radiopharmaceuticals, 2000Co-Authors: Margareta Bjorkman, Ryoji Noyori, Masaaki Suzuki, Hisashi Doi, Bahram Resul, Yasuyoshi Watanabe, Bengt LangstromAbstract:17-(3-[11C]Methylphenyl)-18,19,20-trinor-PGF2αisopropyl ester 2 was synthesised using an improved method for cross-coupling reactions with [11C]Methyl Iodide. The decay-corrected radiochemical yield of 2 was 34 % based on [11C]Methyl Iodide in a synthesis time of 30 min from end of radionuclide production. The specific radioactivity was approximately 100 GBq/µmol and the radiochemical purity was higher than 95 % as determined by analytical LC. In a typical experiment 1.3 GBq of 2 was obtained from 11 GBq of [11C]Methyl Iodide. Copyright © 2000 John Wiley & Sons, Ltd.
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synthesis of 11c 13c labelled prostacyclins
Acta Chemica Scandinavica, 1998Co-Authors: Margareta Bjorkman, Ryoji Noyori, Koichi Kato, Masaaki Suzuki, Yvonne Andersson, Hisashi Doi, Bengt LangstromAbstract:A one-pot synthesis of (15R)-16-(3-[11C]Methylphenyl)-17,18,19, 20-tetranoriso-carbacyclin Methyl ester was performed using a palladium-promoted reaction of [11C]Methyl Iodide with (15R)-16-(3-tri-n-butylstannylphenyl)-17,18,19, 20-tetranorisocarbacyclin Methyl ester. The C-15 epimer (15S)-16-(3-[11C]Methylphenyl)-17,18,19,20-tetranorisocarbacyclin Methyl ester was synthesised in the same way starting from (15S)-16-(3-tributylstannylphenyl)-17,18,19,20-tetranorisocarba cyclin Methyl ester. The decay-corrected radiochemical yields were 33-45% based on [11C]Methyl Iodide produced, and the radiochemical purity of the product was > 95%. The total synthesis time was 35 min, counted from end of radionuclide production to product ready for administration. The 11C-labelled prostacyclin Methyl esters were easily hydrolysed using sodium hydroxide affording the 11C-labelled prostacyclin acids in quantitative yields. The stereoisomers (15R)-16-(3-Methylphenyl)-17,18,19,20-tetranorisocarbacyclin [11C]Methyl ester and (15S)-16-(3-Methylphenyl)-17,18,19,20-tetranorisocarbacyclin [11C]Methyl ester were synthesised by esterification using [11C]Methyl Iodide and the tetrabutylammonium salts of (15R)-16-(3-Methylphenyl)-17,18,19,20-tetranorisocarbacyclin acid and (15S)-16-(3-Methylphenyl)-17,18,19,20-tetranorisocarbacyclin acid, respectively. The decay-corrected radiochemical yields were in the range of 55% counting from [11C]Methyl Iodide produced, and the radiochemical purity of the product was > 95%. The total synthesis time was 35 min, counting from end of radionuclide production to product ready for administration. Both of these labelling methods can be used for labelling with 13C when (13C)Methyl Iodide is used. The methods described herein have already proved important since they enable the in vivo use of PET to study the action of prostacyclins in the brain.
Hisashi Doi - One of the best experts on this subject based on the ideXlab platform.
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pd mediated rapid cross couplings using 11c Methyl Iodide groundbreaking labeling methods in 11c radiochemistry
Journal of Labelled Compounds and Radiopharmaceuticals, 2015Co-Authors: Hisashi DoiAbstract:Prof. Bengt Langstrom is a pioneer in the field of chemistry-driven positron emission tomography (PET) imaging. He has developed a variety of excellent radiolabeling methodologies using the methods of organic chemistry, with the aim of widening the potential of PET in the study of life. Among his groundbreaking achievements in (11) C radiochemistry, there is the discovery of the Pd-mediated rapid cross-coupling reaction using [(11) C]Methyl Iodide. It was first reported by his Uppsala group in 1994-1995 and was further investigated by his and other groups with a view of enhancing its generality and practicability. This reaction is currently considered one of the basic methods for (11) C-labeling of low-weight organic compounds. This paper presents a short summary of the background and the development of Pd-mediated rapid cross-couplings of [(11) C]Methyl Iodide, with a focus not only on organostannanes, but also on organoboranes, organozincs, and terminal acetylene compounds. All these reactions have proven to be dependable (11) C-labeling methodologies that use chemically reliable carbon-carbon bond formation reactions.
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pd0 mediated rapid coupling between Methyl Iodide and heteroarylstannanes an efficient and general method for the incorporation of a positron emitting 11c radionuclide into heteroaromatic frameworks
Chemistry: A European Journal, 2009Co-Authors: Masaaki Suzuki, Takamitsu Hosoya, Kengo Sumi, Hiroko Koyama, Misato Takashimahirano, Hisashi DoiAbstract:The Pd(0)-mediated rapid trapping of Methyl Iodide with an excess amount of a heteroaryl-substituted tributylstannane has been investigated with the aim of incorporating a short-lived (11)C-labelled Methyl group into the heteroaromatic carbon frameworks of important organic compounds, such as drugs with various heteroaromatic structures, in order to execute a positron emission tomography (PET) study of vital systems. The reaction was first performed by using our previously developed CH(3)I/stannane/[Pd(2)(dba)(3)]/P(o-CH(3)C(6)H(4))(3)/CuCl/K(2)CO(3) (1:40:0.5:2:2:2) system in DMF at 60 degrees C for 5 min (conditions A), however, the reaction gave low yields for various heteroaromatic compounds. Increasing the amount of phosphine ligand (conditions B) led to a significant improvement in the yield, but the conditions were still not suitable for a range of basic heteroaromatic structures. Use of the CuBr/CsF system (conditions C) also provided a result similar to that obtained under conditions B with an increased amount of the phosphine. Thus, pyridine and related heteroaromatic compounds remained less reactive substrates. The problem was overcome by replacing the DMF solvent with N-Methyl-2-pyrolidinone (NMP). The reaction in NMP at 60-100 degrees C for 5 min using a CH(3)I/stannane/[Pd(2)(dba)(3)]/P(o-CH(3)C(6)H(4))(3)/CuBr/CsF (1:40:0.5:16:2:5) combination (conditions D) gave the Methylated products in yields of more than 80 % (based on the reaction of CH(3)I) for all of the heteroaromatic compounds listed in this study. Thus, the combined use of NMP and an increased amount of phosphine is important for promoting the reaction efficiently. The use of this general approach to rapid Methylation has been well demonstrated by the synthesis of the PET tracers 2- and 3-[(11)C]Methylpyridines by using [Pd(2)(dba)(3)]/P(o-CH(3)C(6)H(4))(3)/CuBr/CsF (1:16:2:5) in NMP at 60 degrees C for 5 min, which gives the desired products in HPLC analytical yields of 88 and 91 %, respectively.
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rapid Methylation on carbon frameworks useful for the synthesis of 11ch3 incorporated pet tracers pd 0 mediated rapid coupling of Methyl Iodide with an alkenyltributylstannane leading to a 1 Methylalkene
ChemInform, 2006Co-Authors: Takamitsu Hosoya, Hisashi Doi, Masahiro Wakao, Kengo Sumi, Masaaki SuzukiAbstract:The Pd(0)-mediated rapid coupling of Methyl Iodide with an excess of alkenyltributylstannane was examined with the aim of incorporating a short-lived 11C-labeled Methyl group into a biologically significant organic compound with a 1-Methylalkene unit for the synthesis of a PET tracer. Four sets of reaction conditions (A–D) were used, all performed in DMF at 60 °C for 5 min. Condition B, using CH3I/stannane/Pd2(dba)3/P(o-tolyl)3/CuCl/K2CO3 (1 : 40 : 0.5 : 4–6 : 2 : 5), works well in almost all cases. Condition D, using CH3I/stannane/Pd2(dba)3/P(o-tolyl)3/CuX (X = Br, Cl, or I)/CsF (1 : 40 : 0.5–5 : 2–20 : 2–20 : 5–50), shows the best results with regard to general applicability to tin substrates, affording the corresponding Methylated product in >90% yield based on consumption of Methyl Iodide. P(t-Bu)2Me was less effective than P(o-tolyl)3, particularly for α,β-unsaturated carbonyl substrates. No regio- or stereoisomerization occurred under these reaction conditions. The efficiency of the protocol was demonstrated by synthesis of an 11C-Methylated compound.
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rapid Methylation of terminal acetylenes by the stille coupling of Methyl Iodide with alkynyltributylstannanes a general protocol potentially useful for the synthesis of short lived 11ch3 labeled pet tracers with a 1 propynyl group
ChemInform, 2004Co-Authors: Takamitsu Hosoya, Hisashi Doi, Masahiro Wakao, Yurie Kondo, Masaaki SuzukiAbstract:The Pd(0)-mediated rapid coupling (trapping) reaction of Methyl Iodide with an excess amount of alkynyltributylstannane has been developed with the aim to incorporate a short-lived 11C-labeled Methyl group into biologically active organic compounds with a 1-propynyl structural unit.
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synthesis of a 11c labelled prostaglandin f2α analogue using an improved method for stille reactions with 11c Methyl Iodide
Journal of Labelled Compounds and Radiopharmaceuticals, 2000Co-Authors: Margareta Bjorkman, Ryoji Noyori, Masaaki Suzuki, Hisashi Doi, Bahram Resul, Yasuyoshi Watanabe, Bengt LangstromAbstract:17-(3-[11C]Methylphenyl)-18,19,20-trinor-PGF2αisopropyl ester 2 was synthesised using an improved method for cross-coupling reactions with [11C]Methyl Iodide. The decay-corrected radiochemical yield of 2 was 34 % based on [11C]Methyl Iodide in a synthesis time of 30 min from end of radionuclide production. The specific radioactivity was approximately 100 GBq/µmol and the radiochemical purity was higher than 95 % as determined by analytical LC. In a typical experiment 1.3 GBq of 2 was obtained from 11 GBq of [11C]Methyl Iodide. Copyright © 2000 John Wiley & Sons, Ltd.
D Doizi - One of the best experts on this subject based on the ideXlab platform.
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oxygen broadening and shift coefficients in the ν6 band of Methyl Iodide 12ch3i at room temperature
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: Y Attafi, Ben A Hassen, H Aroui, Kwabia F Tchana, Laurent Manceron, Vander J Auwera, A Perrin, S Galalou, D DoiziAbstract:Abstract In this study we report the high-resolution measurements of oxygen pressure- broadening and pressure-induced shift coefficients for rovibrational transitions in the ν6 band of Methyl Iodide (12CH3I), centered at 892.918 cm–1. The results were obtained by analyzing fourteen high-resolution room temperature laboratory absorption spectra with a mono-spectrum non-linear least squares fitting of Voigt profiles. The data were recorded with the Bruker IF125HR Fourier transform spectrometer located at the LISA facility in Creteil, using a White type cell with a path length of 564.9 cm and total pressures up to 295 hPa. The measured oxygen-broadening coefficients range from 0.0648 to 0.1207 cm–1atm–1 at 295 K. The measured shift coefficients were all negative and varied between −0.00044 and −0.04984 cm–1atm–1. The average accuracy on the measured O2-broadening coefficients and pressure shift coefficients was estimated to about 4% and 11%, respectively. The O2-broadening coefficients obtained in the present work are compared with values reported in the literature for the ν5 band of CH3I, showing a satisfactory agreement with an average difference of about 8%. The shift coefficients are compared with values reported in the literature for the ν6 band of CH3F-Ar system, exhibiting the same order of magnitude and trend. The J and K rotational dependences of the O2-broadening coefficients have been observed and the latter modeled using empirical polynomial expansions. On average, the empirical expression reproduces the measured O2-broadening coefficients to within 3%. Using the measured broadening coefficients of the CH3I-O2 and CH3I-N2 [Attafi et al., J Quant Spectrosc Radiat Transf 231 (2019) 1–8] systems, we produced CH3I-air broadening coefficients, ranging from 0.0783 to 0.1385 cm–1atm–1 at 295 K. The present results and the data already available should be valuable not only for predicting the CH3I infrared spectrum in the atmosphere, but also for verifying theoretical calculations of pressure-broadening and pressure-shift coefficients in the ν6 region of Methyl Iodide spectra.
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self and n2 collisional broadening of rovibrational lines in the ν6 band of Methyl Iodide 12ch3i at room temperature the j and k dependence
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: Y Attafi, Ben A Hassen, H Aroui, Kwabia F Tchana, Laurent Manceron, D Doizi, Vander J Auwera, A PerrinAbstract:Abstract Following our recent study devoted to measurements of intensities of rovibrational lines in the ν6 band of Methyl Iodide (12CH3I) centered at 892.918 cm−1, room temperature infrared spectra of Methyl Iodide diluted in nitrogen at fourteen total pressures between 20 and 300 hPa have been recorded using the Fourier transform spectrometer Bruker IF125HR located at the LISA facility in Creteil. Three hundred and forty six N2-broadening coefficients of Methyl Iodide rovibrational lines have been measured in the 824–951 cm−1 spectral range using mono-spectrum non-linear least squares fitting of Voigt profiles. Pressure-induced line shifts were not needed to fit the spectra to the noise level and line mixing effects could be neglected. Six hundred and eight self-broadening coefficients have also been measured in the same spectral range using the pure Methyl Iodide spectra recorded in our previous work. The measured self-broadening coefficients range from 0.1460 to 0.3786 cm−1 atm−1 and the N2-broadening coefficients range from 0.0723 to 0.1481 cm−1 atm−1 at 295 K. The average accuracy on the measured self- and N2-broadening coefficients was estimated to 3%. Comparisons with measurements reported in the literature for the ν5 band of CH3I shows a satisfactory agreement with average differences of 7% and 4% for the self- and N2-broadening coefficients, respectively. The J and K rotational dependences of these coefficients have been observed and the latter modeled using an empirical polynomial expansion. On average, the empirical expression reproduces the measured self- and N2-broadening coefficients to within 3% and 4%, respectively. The data obtained in the present work represent a significant contribution to the determination of broadening coefficients of CH3I and complement the list of line positions and intensities generated in our previous work, thus providing useful spectroscopic information for atmospheric remote sensing and industrial detection of CH3I.
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line intensities for the ν6 and 2ν3 bands of Methyl Iodide 12ch3i
Journal of Quantitative Spectroscopy & Radiative Transfer, 2019Co-Authors: F Kwabiatchana, Y Attafi, Laurent Manceron, D Doizi, Vander J Auwera, A PerrinAbstract:Abstract The goal of this study is to measure for the first time absolute line intensities for the ν6 band of Methyl Iodide (CH3I) centered at 892.918 cm–1. High-resolution Fourier transform spectra were recorded at various pressures for the whole 500–1450 cm–1 spectral range. Using these spectra, a large set of CH3I individual line intensities was measured for the ν6 band. These experimental intensities were least squares fitted to derive the expansion of the ν6 transition moment operator. The theoretical model used to describe the line positions and intensities accounts for the hyperfine structure in the 61 and ground states and for the vibration-rotation resonances that couple the 61 energy levels with those of the 32 and 21 vibrational states [Perrin et al., J. Mol. Spectrosc. 324 (2016) 28–35]. As the 2ν3 band is extremely weak, its associated transition moment operator was estimated from band strength available in the literature. A comprehensive list of line positions and intensities was generated for the ν6 and 2ν3 bands of CH3I at 11 µm, which should be useful for the possible detection of this species by the future IASI-NG satellite instrument (Infrared Atmospheric Sounding Interferometer New Generation), now under preparation ( https://iasi-ng.cnes.fr/en/IASI-NG/index.htm ).
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new analysis of the ν 6 and 2ν 3 bands of Methyl Iodide ch 3 i
Journal of Molecular Spectroscopy, 2016Co-Authors: A Perrin, D Doizi, F Kwabiatchana, I Haykal, L Manceron, G DucrosAbstract:Abstract A new rovibrational study of the ν6 band of Methyl Iodide was conducted to obtain a rather complete line list. A new analysis of line positions was accomplished. The spectrum of this band has been first recorded using the Bruker IFS125HR Fourier transform spectrometer (FTS) at the AILES beamline of the SOLEIL Synchrotron facility and later with the Bruker IFS125HR FTS located at the LISA facility in Creteil. Altogether, about 10,000 lines were assigned for the ν6 and 2ν3 bands up to high quantum numbers (J ⩽ 85 and K ⩽ 20). Because of the large value of the 127I nuclear quadrupole hyperfine constant, a significant portion of these assignments concerns clusters of hyperfine subcomponents, which are easily observable at 11 μm. These infrared data were combined in a least squares fit together with the existing microwave data on rotational transitions within the v6 = 1 and v3 = 2 vibrational states to get the upper state rotational constants and interacting parameters for the v6 = 1 and v3 = 2 states. Due to the high values of quantum numbers achieved during this infrared analysis, the final energy level calculation accounts for aCx ( Δ l = ± 1 ; Δ K = ± 1 ) and an α ( Δ l = ∓ 1 ; Δ K = ± 2 ) types of Coriolis interactions coupling the v6 = 1 energy levels with those from the v3 = 2 and v2 = 1 states, respectively. On the other hand, it proved unnecessary to update the existing hyperfine parameters for the v6 = 1 and v3 = 2 states.
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line positions in the v6 1 band of Methyl Iodide validation of the c3v tds package based on the tensorial formalism
Journal of Quantitative Spectroscopy & Radiative Transfer, 2016Co-Authors: I Haykal, D Doizi, V Boudon, El A Hilali, L Manceron, G DucrosAbstract:Abstract A tensorial formalism adapted to the case of symmetric-top molecules has been recently developed in Dijon (El Hilali et al., J Quant Spectrosc Radiat Transf 2010;111, 1305–1315) [18]. It is based on the O ( 3 ) ⊃ C ∞ v ⊃C3v group chain and allows a systematic expansion of the Hamiltonian and dipole moment operators, including all possible interactions for a given rovibrational polyad system. This suite of programs is used to analyze and simulate the mid-infrared spectrum of Methyl Iodide in order to test its performance. The v6 fundamental band has been recorded using the FTIR Bruker HR125 at the AILES beamline of the SOLEIL Synchrotron facility with the Globar internal source. 3882 lines up to J=61 were assigned and fitted with only 16 tensorial parameters.