The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform
Samir Z Zard - One of the best experts on this subject based on the ideXlab platform.
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Iminyl, amidyl, and carbamyl radicals from O-benzoyl oximes and O-benzoyl hydroxamic acid derivatives
Tetrahedron, 1995Co-Authors: Jean Boivin, Annemarie Schiano, Anne-claude Callier-dublanchet, Béatrice Quiclet-sire, Samir Z ZardAbstract:Abstract Oxime benzoates and O-benzoyl hydroxamic acid derivatives react with Tributylstannane in the presence of AIBN to give iminyl, amidyl, and carbamyl radicals which can be captured by an internal olefin.
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A new source of nitrogen centered radicals
Tetrahedron Letters, 1995Co-Authors: Anne-claude Callier-dublanchet, Béatrice Quiclet-sire, Samir Z ZardAbstract:Abstract Exposure of thiocarbazone derivatives 6b–10b, 11c–13c, and 14a–15a to Tributylstannane in the presence of AIBN leads to various nitrogen centered radicals which are easily captured by an internal olefin.
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amidyl and carbamyl radicals by stannane mediated cleavage of o benzoyl hydroxamic acid derivatives
Tetrahedron Letters, 1994Co-Authors: Anneclaude Callier, Samir Z Zard, Beatrice QuicletsireAbstract:Abstract O-Benzoyl hydroxamic acids react with Tributylstannane in the presence of AIBN to give amidyl or carbamyl radicals which can be captured by an internal olefin.
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iminyl radicals by stannane mediated cleavage of oxime esters
Tetrahedron Letters, 1994Co-Authors: Jean Boivin, Annemarie Schiano, Samir Z ZardAbstract:Abstract Oxime benzoates react with Tributylstannane in the presence of AIBN to give iminyl radicals which can be captured by an internal olefin.
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Iminyl radicals: part II. ring opening of cyclobutyl- and cyclopentyliminyl radicals.
Tetrahedron, 1994Co-Authors: Jean Boivin, Eric Fouquet, Samir Z ZardAbstract:Abstract Slow addition of Tributylstannane to sulphenylimines 2 give the corresponding cycloiminyl radicals 3 which can undergo ring opening, a process that is easily incorporated into complex reaction sequences.
David Crich - One of the best experts on this subject based on the ideXlab platform.
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design synthesis application and recovery of a minimally fluorous diaryl diselenide for the catalysis of stannane mediated radical chain reactions
Tetrahedron, 1999Co-Authors: David Crich, Mathew A LucasAbstract:Abstract The synthesis of a minimally fluorous (52% F) diaryl diselenide is described. On reduction in situ with Tributylstannane this diselenide provides a fluorous selenol which is effective in inhibiting a range of stannane-mediated radical rearrangements, including a cyclopropylcarbinyl ring opening. A method for the recovery of the fluorous diselenide involving continuous extraction in a modified, cooled continuous extractor is described.
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Diverging Effects of Steric Congestion on the Reaction of Tributylstannyl Radicals with Areneselenols and Aryl Bromides and Their Mechanistic Implications
The Journal of organic chemistry, 1999Co-Authors: David Crich, Jae-taeg Hwang, Stéphane Gastaldi, Francesco Recupero, Donald J. WinkAbstract:The effects of bulky ortho,ortho‘ groups on the reactions of aryl bromides and areneselenols with Tributylstannane have been studied. Bulky ortho,ortho‘ groups accelerate the reaction of the bromides with the stannane but retard the reactions of the selenols. On the other hand, ab initio and force field calculations show that introducing bulky ortho substituents into selenols causes a greater increase in strain than in the corresponding bromides. Two possible explanations for the divergent reactivity patterns are advanced. On one hand, it is possible that bromine abstraction by stannyl radicals from aryl bromides proceeds in a single step through a linear transition state whereas the abstraction of SeH from the selenols involves a T-shaped, hypervalent intermediate. Alternatively, it may be that both reactions are concerted with the bromine abstraction having a late transition state and the SeH abstraction an early one. Approximate second-order rate constants for the reaction of Tributylstannane with a ra...
Morris J Robins - One of the best experts on this subject based on the ideXlab platform.
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Biomimetic Simulation of Free Radical-Initiated Cascade Reactions Postulated To Occur at the Active Site of Ribonucleotide Reductases1
Journal of the American Chemical Society, 1999Co-Authors: Morris J Robins, Zhiqiang Guo, And Mirna C. Samano, Stanislaw F. WnukAbstract:Treatment of 5‘-O-nitro esters of nucleosides with Tributylstannane and AIBN at elevated temperatures caused β-scission of the resulting 5‘-oxygen radical to give formaldehyde and dehomologated ery...
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nucleic acid related compounds 77 2 3 didehydro 2 3 dideoxy 2 and 3 methylnucleosides via 3 3 sigmatropic rearrangements of 2 and 3 methylene 3 and 2 o thiocarbonyl derivatives and radical reduction of a 2 chloro 3 methylene analogue
Canadian Journal of Chemistry, 1993Co-Authors: Vincente Samano, Morris J RobinsAbstract:Treatment of 5′-O-(tert-butyldiphenylsilyl)-2′(and 3′)-deoxy-2′(and 3′)-methyleneuridine (and adenosine) derivatives with phenyl chlorothionocarbonate gave the 3′(and 2′)-O-phenoxythiocarbonyl intermediates, which underwent spontaneous [3,3]-sigmatropic rearrangement to give the 2′,3′-didehydro-2′,3′-dideoxy-2′(and 3′)-(phenoxycarbonylthio)methyl analogues. These allylic thioesters were subjected to Tributylstannane-mediated hydrodesulfurization and deprotection to give 2′,3′-didehydro-2′,3′-dideoxy-2′(and 3′)-methyluridine (and adenosine). Tributylstannane-mediated hydrodehalogenation of a 2′-chloro-2′,3′-dideoxy-3′-methyleneuridine derivative afforded the 2′,3′-didehydro-2′,3′-dideoxy-3′-methyl product of allylic transposition exclusively.
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Nucleic acid related compounds. 77. 2′,3′-Didehydro-2′,3′-dideoxy-2′(and 3′)-methylnucleosides via [3,3]-sigmatropic rearrangements of 2′(and 3′)-methylene-3′(and 2′)-O-thiocarbonyl derivatives and radical reduction of a 2′-chloro-3′-methylene analog
Canadian Journal of Chemistry, 1993Co-Authors: Vincente Samano, Morris J RobinsAbstract:Treatment of 5′-O-(tert-butyldiphenylsilyl)-2′(and 3′)-deoxy-2′(and 3′)-methyleneuridine (and adenosine) derivatives with phenyl chlorothionocarbonate gave the 3′(and 2′)-O-phenoxythiocarbonyl intermediates, which underwent spontaneous [3,3]-sigmatropic rearrangement to give the 2′,3′-didehydro-2′,3′-dideoxy-2′(and 3′)-(phenoxycarbonylthio)methyl analogues. These allylic thioesters were subjected to Tributylstannane-mediated hydrodesulfurization and deprotection to give 2′,3′-didehydro-2′,3′-dideoxy-2′(and 3′)-methyluridine (and adenosine). Tributylstannane-mediated hydrodehalogenation of a 2′-chloro-2′,3′-dideoxy-3′-methyleneuridine derivative afforded the 2′,3′-didehydro-2′,3′-dideoxy-3′-methyl product of allylic transposition exclusively.
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Efficient reduction of azides to amines with Tributylstannane. High-yield syntheses of amino and diamino deoxynucleosides
Tetrahedron Letters, 1991Co-Authors: Mirna C. Samano, Morris J RobinsAbstract:Abstract Treatment of unprotected azido-deoxynucleosides with Tributylstannane/AIBN in hot benzene/DMAC (or silyl-protected derivatives in benzene) resulted in formation of the corresponding amino-deoxynucleosides in high isolated yields. A radical process is indicated.
Bernd Giese - One of the best experts on this subject based on the ideXlab platform.
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Tris(Trimethylsilyl)Silane
Organic Syntheses, 2003Co-Authors: Joachim Dickhaut, Bernd GieseAbstract:Tris(trimethylsilyl)silane product: Tris(trimethylsilyl)silane 1 reactant: Tributylstannane Keywords: metalation reactions, silicon; reduction, miscellaneous; silylation; tetrakis(trimethylsilyl)silane-methyllithium solid residue, potentially pyrophoric
Masahiro Funato - One of the best experts on this subject based on the ideXlab platform.
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Palladium-catalyzed silylation of allylic acetates with hexamethyldisilane or (trimethylsilyl)Tributylstannane
The Journal of Organic Chemistry, 1993Co-Authors: Yasushi Tsuji, Satoshi Kajita, Shinya Isobe, Masahiro FunatoAbstract:Various allylic acetates (1a-j) are silylated with hexamethyldisilane (Me 3 SiSiMe 3 , 2) in the presence of a catalytic amount of Pd(DBA) 2 and LiCl at 100 o C to afford the corresponding allylic silanes in high yields. In addition, (trimethylsilyl)Tributylstannane (Me 3 SiSnBu 3 , 3) can be used for the silylation of aromatic allylic acetates 1g-j at room temperature
