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Takeaki Naito - One of the best experts on this subject based on the ideXlab platform.
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radical cyclization in heterocycle synthesis part 13 Sulfanyl radical addition cyclization of oxime ethers and hydrazones connected with alkenes for synthesis of cyclic β amino acids
Tetrahedron, 2002Co-Authors: Okiko Miyata, Kanami Muroya, Tomoko Kobayashi, Rina Yamanaka, Seiko Kajisa, Junko Koide, Takeaki NaitoAbstract:Abstract A combination of Sulfanyl radical addition–cyclization of the oxime ethers and hydrazones connected with alkenes and subsequent conversion of a phenylSulfanylmethyl group to a carboxyl group provides a novel method for the construction of the cyclic β-amino acids. Upon treatment with thiophenol in the presence of AIBN, the oxime ethers and hydrazones smoothly underwent Sulfanyl radical addition-cyclization to give the 2-(phenylSulfanylmethyl)cycloalkylamine. This method was successfully applied to the practical synthesis of 2-aminocyclopentanecarboxylic acid and 4-amino-3-pyrrolidinecarboxylic acid.
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Radical cyclization in heterocycle synthesis. Part 13: Sulfanyl radical addition–cyclization of oxime ethers and hydrazones connected with alkenes for synthesis of cyclic β-amino acids
Tetrahedron, 2002Co-Authors: Okiko Miyata, Kanami Muroya, Tomoko Kobayashi, Rina Yamanaka, Seiko Kajisa, Junko Koide, Takeaki NaitoAbstract:Abstract A combination of Sulfanyl radical addition–cyclization of the oxime ethers and hydrazones connected with alkenes and subsequent conversion of a phenylSulfanylmethyl group to a carboxyl group provides a novel method for the construction of the cyclic β-amino acids. Upon treatment with thiophenol in the presence of AIBN, the oxime ethers and hydrazones smoothly underwent Sulfanyl radical addition-cyclization to give the 2-(phenylSulfanylmethyl)cycloalkylamine. This method was successfully applied to the practical synthesis of 2-aminocyclopentanecarboxylic acid and 4-amino-3-pyrrolidinecarboxylic acid.
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Sulfanyl radical addition-cyclization and its synthetic application
Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule C-chimie, 2001Co-Authors: Okiko Miyata, Takeaki NaitoAbstract:Abstract This review summarizes a new efficient carbon–carbon bond-forming reaction based on Sulfanyl radical addition–cyclization, which proceeds by the formation of a carbon-centered radical species generated by the addition of a Sulfanyl radical to a multiple bond and then intramolecular addition of the resulting carbon-centered radical to a multiple bond. The synthetic potentiality was demonstrated by the syntheses of anantine, oxo-parabenzlactone, cispentacin, vitamin D, and α-kainic acid.
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Radical cyclisation in heterocycle synthesis. Part 1. Sulfanyl radical addition–cyclisation of dienylamides for lactam synthesis
Journal of The Chemical Society-perkin Transactions 1, 1995Co-Authors: Takeaki Naito, Yuko Honda, Okiko Miyata, Ichiya NinomiyaAbstract:A new method for the synthesis of five- to eight-membered lactams by Sulfanyl radical mediated addition–cyclisation of dienylamides is described. The Sulfanyl radical addition–cyclisation of the dienylamide 1 was systematically investigated under four different conditions and was found to give the cyclised lactams 2–6 in 54–79% yield. The stereo- and regio-selectivity of Sulfanyl radical addition–cyclisation was established from the preferential formation of the trans-cyclised lactam 3 and also from the substituent effects in the Cyclisation of the dienylamides 11–18. The Sulfanyl radical mediated addition–cyclisation was successfully applied to the construction of the six- and eight-membered lactams 28a, b.
Okiko Miyata - One of the best experts on this subject based on the ideXlab platform.
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radical cyclization in heterocycle synthesis part 13 Sulfanyl radical addition cyclization of oxime ethers and hydrazones connected with alkenes for synthesis of cyclic β amino acids
Tetrahedron, 2002Co-Authors: Okiko Miyata, Kanami Muroya, Tomoko Kobayashi, Rina Yamanaka, Seiko Kajisa, Junko Koide, Takeaki NaitoAbstract:Abstract A combination of Sulfanyl radical addition–cyclization of the oxime ethers and hydrazones connected with alkenes and subsequent conversion of a phenylSulfanylmethyl group to a carboxyl group provides a novel method for the construction of the cyclic β-amino acids. Upon treatment with thiophenol in the presence of AIBN, the oxime ethers and hydrazones smoothly underwent Sulfanyl radical addition-cyclization to give the 2-(phenylSulfanylmethyl)cycloalkylamine. This method was successfully applied to the practical synthesis of 2-aminocyclopentanecarboxylic acid and 4-amino-3-pyrrolidinecarboxylic acid.
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Radical cyclization in heterocycle synthesis. Part 13: Sulfanyl radical addition–cyclization of oxime ethers and hydrazones connected with alkenes for synthesis of cyclic β-amino acids
Tetrahedron, 2002Co-Authors: Okiko Miyata, Kanami Muroya, Tomoko Kobayashi, Rina Yamanaka, Seiko Kajisa, Junko Koide, Takeaki NaitoAbstract:Abstract A combination of Sulfanyl radical addition–cyclization of the oxime ethers and hydrazones connected with alkenes and subsequent conversion of a phenylSulfanylmethyl group to a carboxyl group provides a novel method for the construction of the cyclic β-amino acids. Upon treatment with thiophenol in the presence of AIBN, the oxime ethers and hydrazones smoothly underwent Sulfanyl radical addition-cyclization to give the 2-(phenylSulfanylmethyl)cycloalkylamine. This method was successfully applied to the practical synthesis of 2-aminocyclopentanecarboxylic acid and 4-amino-3-pyrrolidinecarboxylic acid.
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Sulfanyl radical addition-cyclization and its synthetic application
Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule C-chimie, 2001Co-Authors: Okiko Miyata, Takeaki NaitoAbstract:Abstract This review summarizes a new efficient carbon–carbon bond-forming reaction based on Sulfanyl radical addition–cyclization, which proceeds by the formation of a carbon-centered radical species generated by the addition of a Sulfanyl radical to a multiple bond and then intramolecular addition of the resulting carbon-centered radical to a multiple bond. The synthetic potentiality was demonstrated by the syntheses of anantine, oxo-parabenzlactone, cispentacin, vitamin D, and α-kainic acid.
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Radical cyclisation in heterocycle synthesis. Part 1. Sulfanyl radical addition–cyclisation of dienylamides for lactam synthesis
Journal of The Chemical Society-perkin Transactions 1, 1995Co-Authors: Takeaki Naito, Yuko Honda, Okiko Miyata, Ichiya NinomiyaAbstract:A new method for the synthesis of five- to eight-membered lactams by Sulfanyl radical mediated addition–cyclisation of dienylamides is described. The Sulfanyl radical addition–cyclisation of the dienylamide 1 was systematically investigated under four different conditions and was found to give the cyclised lactams 2–6 in 54–79% yield. The stereo- and regio-selectivity of Sulfanyl radical addition–cyclisation was established from the preferential formation of the trans-cyclised lactam 3 and also from the substituent effects in the Cyclisation of the dienylamides 11–18. The Sulfanyl radical mediated addition–cyclisation was successfully applied to the construction of the six- and eight-membered lactams 28a, b.
Jose L Garciaruano - One of the best experts on this subject based on the ideXlab platform.
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synthesis of optically pure vic Sulfanyl amines mediated by a remote sulfinyl group
ChemInform, 2012Co-Authors: Yolanda Arroyo, Inés Alonso, Ascension M Sanztejedor, Jose L GarciaruanoAbstract:Treatment of the sulfoxide (I) with N-phenyl and N-methoxyphenyl aldimines allows highly stereoselective access to syn-Sulfanyl amines.
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synthesis of optically pure vic Sulfanyl amines mediated by a remote sulfinyl group
Organic Letters, 2011Co-Authors: Yolanda Arroyo, Inés Alonso, Ascension M Sanztejedor, Jose L GarciaruanoAbstract:Enantiomerically pure syn-1,2-diaryl-1,2-Sulfanylamine derivatives can be obtained in a completely stereoselective manner by reaction of the benzylcarbanion Li-(S)-1 with N-phenyl (or PMP)-arylidene aldimines and further desulfinylation with t-BuLi. Theoretical studies at the DFT (mPW1PW91) level with the CPCM model, by using the Gaussian09 program, provide a good explanation for the stereochemical results.
Yolanda Arroyo - One of the best experts on this subject based on the ideXlab platform.
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synthesis of optically pure vic Sulfanyl amines mediated by a remote sulfinyl group
ChemInform, 2012Co-Authors: Yolanda Arroyo, Inés Alonso, Ascension M Sanztejedor, Jose L GarciaruanoAbstract:Treatment of the sulfoxide (I) with N-phenyl and N-methoxyphenyl aldimines allows highly stereoselective access to syn-Sulfanyl amines.
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synthesis of optically pure vic Sulfanyl amines mediated by a remote sulfinyl group
Organic Letters, 2011Co-Authors: Yolanda Arroyo, Inés Alonso, Ascension M Sanztejedor, Jose L GarciaruanoAbstract:Enantiomerically pure syn-1,2-diaryl-1,2-Sulfanylamine derivatives can be obtained in a completely stereoselective manner by reaction of the benzylcarbanion Li-(S)-1 with N-phenyl (or PMP)-arylidene aldimines and further desulfinylation with t-BuLi. Theoretical studies at the DFT (mPW1PW91) level with the CPCM model, by using the Gaussian09 program, provide a good explanation for the stereochemical results.
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Stereoselective addition of alpha-methylsulfenyl benzyl carbanions to N-sulfinylketimines: asymmetric synthesis of alpha,alpha-dibranched beta-Sulfanyl amines.
Journal of Organic Chemistry, 2009Co-Authors: Yolanda Arroyo, Angela Meana, M. Ascension Sanz‐tejedor, Inés Alonso, José L. García RuanoAbstract:(R)- and (S)-N-sulfinylketimines react with the ortho-sulfinyl benzyl carbanion derived from (S)-1 affording epimeric mixtures at the benzylic carbon of α,α-dibranched β-Sulfanyl amines. The N-sulfinyl group completely controls the configuration at the quaternary carbon bonded to the nitrogen, whereas the C-sulfinyl group is responsible for the level of asymmetric induction. High stereoselectivity can be achieved when the configuration at the sulfur atoms of the reagents are opposite (matched pair). After a two-step desulfinylation process, this reaction provides a procedure for synthesizing diastereomerically pure syn-1,2-Sulfanyl amines containing a chiral quaternary carbon adjacent to nitrogen.
Kristine A Nolin - One of the best experts on this subject based on the ideXlab platform.
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synthesis of β Sulfanyl ketones via a tandem rearrangement conjugate addition reaction catalyzed by a re v oxo complex
Tetrahedron Letters, 2013Co-Authors: Alyson E Garst, Alexandra D Badiceanu, Kristine A NolinAbstract:A method for synthesizing β-Sulfanyl ketones via a tandem rearrangement and conjugate addition reaction has been developed. This methodology provides access to a range of β-Sulfanyl ketones through the rearrangement of propargyl alcohols to the corresponding enones followed by the conjugate addition of unactivated thiols. The one-pot, tandem transformation is catalyzed by ReOCl3(OPPh3)(S(CH3)2) affording aryl and alkyl β-Sulfanyl ketones in good to excellent yield.
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conjugate addition of unactivated thiols to α β unsaturated ketones catalyzed by a bifunctional rhenium v oxo complex
ChemInform, 2012Co-Authors: Allan Peng, Ross Rosenblatt, Kristine A NolinAbstract:A moisture-tolerant complex is described as convenient catalyst for the title reaction which affords biologically interesting β-Sulfanyl ketone structures.