The sulfinyl moiety in Lewis base-promoted allylations
摘要:
By employing Senanayake's oxathiazolidine-2-oxide reagent, a collection of sulfinamides was prepared and provided the first examples of sulfinamides promoting the allylation of benzaldehyde and N-benzoylhydrazones with allyltrichlorosilane. The optimum sulfinamide-derived Lewis base promoter displays comparable activity to the best sulfinyl-based Lewis bases reported. The use of bis-sulfoxides is also discussed. (C) 2009 Elsevier Ltd. All rights reserved.
Treatment of sulphinamides with alcohols in the presence of strong acids results in the formation of sulphinates in good yields; this reaction has been shown to proceed with inversion of configuration at the sulphinyl centre and high stereospecificity which is dependent on the structure of the alcohol used.
Acid Catalyzed Alcoholysis of Sulfinamides: Unusual Stereochemistry, Kinetics and a Question of Mechanism Involving Sulfurane Intermediates and Their Pseudorotation
formed in this reaction with a full or predominant inversion of configuration at chiral sulfur or with predominant retention of configuration. The steric course of the reaction depends mainly on the size of the dialkylamido group in the sulfinamides and of the alcohols used as nucleophilic reagents. It has been found that bulky reaction components preferentially form sulfinates with retention of configuration
Studies on Chiral Organosulfur Compounds. V. Palladium-Catalyzed Intramolecular Asymmetric Metallo-Ene Reactions via Chiral Allylic Sulfinate-Sulfone Rearrangements.
作者:Kunio HIROI、Kazushige HIRASAWA
DOI:10.1248/cpb.42.1036
日期:——
A palladium-catalyzed intramolecular asymmetric metallo-ene reaction was accomplished using a chiral allylic sulfone (prepared by thermal rearrangement of an optically active allylic sulfinate) as an enophile. The stereoselectivity of the reaction was determined by high-performance liquid chromatography with a chiral column. A plausible mechanistic pathway for this asymmetric cyclization is presented.
Stereochemical studies of the palladium-catalyzed rearrangements of chiral 2-alkynyl sulfinates into chiral allenyl sulfones
作者:Kunio Hiroi、Fumiko Kato
DOI:10.1016/s0040-4020(00)01111-x
日期:2001.2
determined. The conversion rate was measured by the HPLC analysis in accordance with the elapse of the reaction time, and the rather marked difference of the rate was observed between the diastereomeric sulfinates. A novel mechanism for this transformation with palladium catalysts is proposed.
The first stereoselective synthesis of optically active thiosulfinates
作者:Józef Drabowicz、Marian Mikoł
DOI:10.1016/s0040-4039(01)80925-4
日期:1985.1
Treatment of opticallyactive -toluenesulfinamides (1) with thiols (2) in the presence of trifluoroacetic acid was found to give opticallyactive -toluenethio-sulfinates (3) with predominant inversion of configuration. Stereospecificity of this reaction varies from 30 to 80%. Some mechanistic aspects of the reaction are also discussed.