The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
Rocío Gámez-montaño - One of the best experts on this subject based on the ideXlab platform.
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The Ugi Reaction of Cyanoacetic Acid as a Route to Tetramic Acid Derivatives.
ChemInform, 2016Co-Authors: Nancy V. Alvarez-rodríguez, Aurélie Dos Santos, Laurent El Kaim, Rocío Gámez-montañoAbstract:The Ugi one-pot reaction of Cyanoacetic Acid (I), aromatic aldehydes [e.g. (III)], amines [e.g. (II)], and isocyanides [e.g. (IV)] produces aminopyrrolinone derivatives [e.g. (V)].
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The Ugi Reaction of Cyanoacetic Acid as a Route to Tetramic Acid Derivatives
Synlett, 2015Co-Authors: Nancy V. Alvarez-rodríguez, Aurélie Dos Santos, Laurent El Kaim, Rocío Gámez-montañoAbstract:Ugi adducts of Cyanoacetic Acid and aromatic aldehydes are readily cyclized under basic conditions leading to one-pot formation of aminopyrrolinone derivatives.
Mohd. Shkir - One of the best experts on this subject based on the ideXlab platform.
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electro optical and charge injection investigations of the donor π acceptor triphenylamine oligocene thiophene pyrimidine and Cyanoacetic Acid based multifunctional dyes
Journal of King Saud University - Science, 2015Co-Authors: Ahmad Irfan, Shabbir Muhammad, Aijaz Rasool Chaudhry, Abul Kalam, Abdullah G Alsehemi, M S Alassiri, Mohd. ShkirAbstract:Abstract The corner stone of present study is to tune the electro-optical and charge transport properties of donor-bridge-acceptor (D- π -A) triphenylamine (TPA) derivatives. In the present investigation, an electron deficient moiety (pyrimidine), electron-rich moiety (thiophene) and oligocene (benzene, naphthalene, anthracene, tetracene and pentacene) have been incorporated as π -spacer between the donor TPA unit and Cyanoacetic Acid acceptor and anchoring group. The elongation of bridge usually affects the energy levels, i.e., higher the highest occupied molecular orbital (HOMO) while lower the lowest unoccupied molecular orbital (LUMO) thus reduces the HOMO–LUMO energy gap. The lowered LUMO energy levels of cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-tetraceno[2,3-b]thiophen-8-yl}-acetic Acid (TPA-PTT4) and cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-pentaceno[2,3-b]thiophen-9-yl}-acetic Acid (TPA-PPT5) dyes revealed that electron injected from dye to semiconductor surface might be auxiliary stable resulting in impediment of quenching. The broken co-planarity between the π -spacer conceiving LUMO and the TPA moiety would help to impede the recombination process. Moreover, it is expected that TPA derivatives with the tetracenothiophene and pentacenothiophene moieties as π -bridge would show better photovoltaic performance due to lowered LUMO energy level, higher electronic coupling constant, light harvesting efficiency and electron injection values.
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Electro-optical and charge injection investigations of the donor-π-acceptor triphenylamine, oligocene–thiophene–pyrimidine and Cyanoacetic Acid based multifunctional dyes
Journal of King Saud University - Science, 2015Co-Authors: Ahmad Irfan, Abdullah G. Al-sehemi, Shabbir Muhammad, Mohammad S. Al-assiri, Aijaz Rasool Chaudhry, Abul Kalam, Mohd. ShkirAbstract:Abstract The corner stone of present study is to tune the electro-optical and charge transport properties of donor-bridge-acceptor (D- π -A) triphenylamine (TPA) derivatives. In the present investigation, an electron deficient moiety (pyrimidine), electron-rich moiety (thiophene) and oligocene (benzene, naphthalene, anthracene, tetracene and pentacene) have been incorporated as π -spacer between the donor TPA unit and Cyanoacetic Acid acceptor and anchoring group. The elongation of bridge usually affects the energy levels, i.e., higher the highest occupied molecular orbital (HOMO) while lower the lowest unoccupied molecular orbital (LUMO) thus reduces the HOMO–LUMO energy gap. The lowered LUMO energy levels of cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-tetraceno[2,3-b]thiophen-8-yl}-acetic Acid (TPA-PTT4) and cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-pentaceno[2,3-b]thiophen-9-yl}-acetic Acid (TPA-PPT5) dyes revealed that electron injected from dye to semiconductor surface might be auxiliary stable resulting in impediment of quenching. The broken co-planarity between the π -spacer conceiving LUMO and the TPA moiety would help to impede the recombination process. Moreover, it is expected that TPA derivatives with the tetracenothiophene and pentacenothiophene moieties as π -bridge would show better photovoltaic performance due to lowered LUMO energy level, higher electronic coupling constant, light harvesting efficiency and electron injection values.
V. Mahadevan - One of the best experts on this subject based on the ideXlab platform.
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Redox polymerization of 2‐hydroxyethyl methacrylate, 2. Kinetics, mechanism and solvent effect using manganese triacetate/Cyanoacetic Acid as the redox system
Macromolecular Chemistry and Physics, 1996Co-Authors: Jainamma Mathew, V. MahadevanAbstract:Polymerization of 2-hydroxyethyl methacrylate (HEMA) initiated by the redox system manganese triacetate (Mn(III)/Cyanoacetic Acid (CAA) was investigated kinetically in DMF and in HOAc/water (80:20 v/v). Monomer (M) conversion was followed gravimetrically. Polymerization was carried out at 31°C and at 41°C. The rate of polymerization R p in DMF is expressed by the equation, R p α [M] 1,4 [Mn(III)] 0,4 [CAA] 0,4 . In HOAc/water, the polymerization exhibited a strong dependence on the concentration of Mn(III). That is, at low concentrations of Mn(III), the rate variations are [M] 1,0 , [CAA] 0,5 and [Mn(III)] 0,5 , while at high Mn(III) concentration the polymerization rates are independent of [Mn(III)] and vary as a function of [M] 1,5 and [CAA] 0,5 . Enhanced oxidation of the primary radicals by Mn(III) at higher concentrations has been elicited to explain the observed orders. The degree of polymerization was found to increase with increase in concentrations of monomer and decrease in concentrations of CAA and Mn(III). The polymerization rates as well as the molecular weights of the polymers are higher in HOAc/water than in DMF. The enhanced polymerization rates have been attributed to the increased propagation and the reduced termination rates.
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redox polymerization of 2 hydroxyethyl methacrylate 2 kinetics mechanism and solvent effect using manganese triacetate Cyanoacetic Acid as the redox system
Macromolecular Chemistry and Physics, 1996Co-Authors: Jainamma Mathew, V. MahadevanAbstract:Polymerization of 2-hydroxyethyl methacrylate (HEMA) initiated by the redox system manganese triacetate (Mn(III)/Cyanoacetic Acid (CAA) was investigated kinetically in DMF and in HOAc/water (80:20 v/v). Monomer (M) conversion was followed gravimetrically. Polymerization was carried out at 31°C and at 41°C. The rate of polymerization R p in DMF is expressed by the equation, R p α [M] 1,4 [Mn(III)] 0,4 [CAA] 0,4 . In HOAc/water, the polymerization exhibited a strong dependence on the concentration of Mn(III). That is, at low concentrations of Mn(III), the rate variations are [M] 1,0 , [CAA] 0,5 and [Mn(III)] 0,5 , while at high Mn(III) concentration the polymerization rates are independent of [Mn(III)] and vary as a function of [M] 1,5 and [CAA] 0,5 . Enhanced oxidation of the primary radicals by Mn(III) at higher concentrations has been elicited to explain the observed orders. The degree of polymerization was found to increase with increase in concentrations of monomer and decrease in concentrations of CAA and Mn(III). The polymerization rates as well as the molecular weights of the polymers are higher in HOAc/water than in DMF. The enhanced polymerization rates have been attributed to the increased propagation and the reduced termination rates.
Nancy V. Alvarez-rodríguez - One of the best experts on this subject based on the ideXlab platform.
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The Ugi Reaction of Cyanoacetic Acid as a Route to Tetramic Acid Derivatives.
ChemInform, 2016Co-Authors: Nancy V. Alvarez-rodríguez, Aurélie Dos Santos, Laurent El Kaim, Rocío Gámez-montañoAbstract:The Ugi one-pot reaction of Cyanoacetic Acid (I), aromatic aldehydes [e.g. (III)], amines [e.g. (II)], and isocyanides [e.g. (IV)] produces aminopyrrolinone derivatives [e.g. (V)].
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The Ugi Reaction of Cyanoacetic Acid as a Route to Tetramic Acid Derivatives
Synlett, 2015Co-Authors: Nancy V. Alvarez-rodríguez, Aurélie Dos Santos, Laurent El Kaim, Rocío Gámez-montañoAbstract:Ugi adducts of Cyanoacetic Acid and aromatic aldehydes are readily cyclized under basic conditions leading to one-pot formation of aminopyrrolinone derivatives.
Ahmad Irfan - One of the best experts on this subject based on the ideXlab platform.
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electro optical and charge injection investigations of the donor π acceptor triphenylamine oligocene thiophene pyrimidine and Cyanoacetic Acid based multifunctional dyes
Journal of King Saud University - Science, 2015Co-Authors: Ahmad Irfan, Shabbir Muhammad, Aijaz Rasool Chaudhry, Abul Kalam, Abdullah G Alsehemi, M S Alassiri, Mohd. ShkirAbstract:Abstract The corner stone of present study is to tune the electro-optical and charge transport properties of donor-bridge-acceptor (D- π -A) triphenylamine (TPA) derivatives. In the present investigation, an electron deficient moiety (pyrimidine), electron-rich moiety (thiophene) and oligocene (benzene, naphthalene, anthracene, tetracene and pentacene) have been incorporated as π -spacer between the donor TPA unit and Cyanoacetic Acid acceptor and anchoring group. The elongation of bridge usually affects the energy levels, i.e., higher the highest occupied molecular orbital (HOMO) while lower the lowest unoccupied molecular orbital (LUMO) thus reduces the HOMO–LUMO energy gap. The lowered LUMO energy levels of cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-tetraceno[2,3-b]thiophen-8-yl}-acetic Acid (TPA-PTT4) and cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-pentaceno[2,3-b]thiophen-9-yl}-acetic Acid (TPA-PPT5) dyes revealed that electron injected from dye to semiconductor surface might be auxiliary stable resulting in impediment of quenching. The broken co-planarity between the π -spacer conceiving LUMO and the TPA moiety would help to impede the recombination process. Moreover, it is expected that TPA derivatives with the tetracenothiophene and pentacenothiophene moieties as π -bridge would show better photovoltaic performance due to lowered LUMO energy level, higher electronic coupling constant, light harvesting efficiency and electron injection values.
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The effect of anchoring groups on the electro-optical and charge injection in triphenylamine derivatives@Ti6O12
Journal of Theoretical and Computational Chemistry, 2015Co-Authors: Ahmad Irfan, Abdullah G. Al-sehemi, Shabbir Muhammad, Mohammad S. Al-assiri, Abul Kalam, Aijaz Rasool ChaudhryAbstract:The triphenylamine (TPA), thiophene and pyrimidine are being used as efficient advanced functional semiconductor materials. In the present study, some new TPA donor–π–acceptor derivatives were designed where TPA moiety acts as donor, thiophene-pyrimidine π-bridge and acetic/Cyanoacetic Acid as acceptor. The ground-state geometries were optimized at B3LYP/6-31G** level of theory. The excitation energies and oscillator strengths were computed at TD-CAM-B3LYP/6-31G** (polarizable continuum model (PCM), in methanol) level of theory. The electronic, photophysical and charge transport properties were calculated wherever possible the computed values were compared with the available experimental as well as computational data. The electron injection (ΔGinject), relative electron injection , electron coupling constants (∣VRP∣) and light harvesting efficiencies (LHE) have been calculated and compared with referenced compounds. The energies of the lowest unoccupied molecular orbitals (ELUMOs), diagonal bandgaps and energy level offsets were studied to shed light on the electron transport behavior. The effect of anchoring groups (acetic Acid and Cyanoacetic Acid) was studied on the properties of interests in the dye and dye@Ti6O12. It was observed that after interaction of dye with the TiO2 cluster intra-molecular charge transport enhanced from HOMO of the dye to LUMO of the semiconductor cluster. The Cyanoacetic Acid anchoring group leads the superior LHE, ΔGinject and ∣VRP∣ which might improve the solar cell performance.
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Electro-optical and charge injection investigations of the donor-π-acceptor triphenylamine, oligocene–thiophene–pyrimidine and Cyanoacetic Acid based multifunctional dyes
Journal of King Saud University - Science, 2015Co-Authors: Ahmad Irfan, Abdullah G. Al-sehemi, Shabbir Muhammad, Mohammad S. Al-assiri, Aijaz Rasool Chaudhry, Abul Kalam, Mohd. ShkirAbstract:Abstract The corner stone of present study is to tune the electro-optical and charge transport properties of donor-bridge-acceptor (D- π -A) triphenylamine (TPA) derivatives. In the present investigation, an electron deficient moiety (pyrimidine), electron-rich moiety (thiophene) and oligocene (benzene, naphthalene, anthracene, tetracene and pentacene) have been incorporated as π -spacer between the donor TPA unit and Cyanoacetic Acid acceptor and anchoring group. The elongation of bridge usually affects the energy levels, i.e., higher the highest occupied molecular orbital (HOMO) while lower the lowest unoccupied molecular orbital (LUMO) thus reduces the HOMO–LUMO energy gap. The lowered LUMO energy levels of cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-tetraceno[2,3-b]thiophen-8-yl}-acetic Acid (TPA-PTT4) and cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-pentaceno[2,3-b]thiophen-9-yl}-acetic Acid (TPA-PPT5) dyes revealed that electron injected from dye to semiconductor surface might be auxiliary stable resulting in impediment of quenching. The broken co-planarity between the π -spacer conceiving LUMO and the TPA moiety would help to impede the recombination process. Moreover, it is expected that TPA derivatives with the tetracenothiophene and pentacenothiophene moieties as π -bridge would show better photovoltaic performance due to lowered LUMO energy level, higher electronic coupling constant, light harvesting efficiency and electron injection values.
