82202-15-1Relevant academic research and scientific papers
Competition between electroauxiliaries. Selective electrochemical oxidation of heteroatom compounds having silicon and tin on the same carbon
Yoshida, Jun-Ichi,Watanabe, Mitsuru,Toshioka, Hideaki,Imagawa, Masayuki,Suga, Seiji
, p. 1011 - 1012 (2007/10/03)
The selective electrochemical oxidation of heteroatom compounds having two different types of electroauxiliaries, i.e. silicon and tin on the same α carbon has been achieved. The C-Sn bond was cleaved selectively and a nucleophile was introduced. The seco
Carbonium Ion Rearrangements Controlled by the Presence of a Silyl Group
Fleming, Ian,Patel, Shailesh K.,Urch, Christopher J.
, p. 115 - 124 (2007/10/02)
γ-Silyl tertiary alcohols rearrange in protic acid with 1,2-shift of hydride, phenyl, or alkyl groups, and loss of the silyl group to give alkenes.The placing of the silyl group thus controls the carbonium ion rearrangement in a preparatively useful way.Methoxycarbonyl groups do not migrate; instead, cyclopropanes are formed, except when the conformation suitable for cyclopropane formation is unattainable.When the alkene product is 2,2-disubstituted, it can be reprotonated under the reaction conditions and does not therefore always survive.This can be avoided by carrying out the reaction using a Lewis acid on the silyl ether.The starting γ-silyl alcohols are prepared by a variety of versatile methods.
α-ALKYLATION AND α-ALKYLIDENATION OF CARBONYL COMPOUNDS BY O-SILYLATED ENOLATE PHENYLTHIOALKYLATION
Paterson, Ian
, p. 4207 - 4220 (2007/10/02)
For many reactions next to a carbonyl group, the use of O-silylated enolate chemistry offers improvements in yield and selectivity over the corresponding reactions of Group I metal enolates.In the case of α-alkylation of carbonyl compounds, Lewis acid (TiCl4 or ZnBr2) promoted phenylthioalkylation of O-silylated enolates 3 by α-chlorosulphides 4 (R3=H, Me, Prn, Pri, Bui, and Me3Si), followed by reductive sulphur removal by Raney nickel, 5->6, is found to be a reliable method for this synthetically important C-C bond forming step.An alternative sulphur elimination pathway via the sulphoxide, 5->7, allows the regio- and stereocontrolled α-alkylidenation of carbonyl compounds.The phenylthioalkylation reaction is applicable to ketones, aldehydes, esters, and lactones.
THE PREPARATION β-KETOALDEHYDES
Ager, David J.
, p. 419 - 422 (2007/10/02)
β-Ketoaldehydes(7) were prepared by the addition of bromophenylthiotrimethylsilylmethane(6) to trimethylsilyl enol ethers(3) followed by a sila-Pummerer rearrangement and hydrolysis.
THE SYNTHESIS OF αβ-UNSATURATED KETONES FROM β-SILYLENONES AND β-SILYLYNONES
Fleming, Ian,Perry, David A.
, p. 4027 - 4034 (2007/10/02)
Conjugate addition, followed by alkylation, bromination and desilyl-bromination make the β-silylketone (4) an a3d2-synthon (5) and the β-silylynone (6) a 2a3d2-synthon (7).
