Enantioselective preparation of 2-substituted- 1,3-dithiane 1-oxides using modified sharpless sulphoxidation procedures
作者:Philip C. Bulman Page、Robin D. Wilkes、Emest S. Namwindwa、Michael J. Witty
DOI:10.1016/0040-4020(95)01029-7
日期:1996.2
carried out using modified Sharpless conditions to furnish the corresponding sulphoxides in optically enriched form. Deacylation of 2-acyl-1,3-dithiane 1-oxide derivatives allows the preparation of 2-alkyl-1,3-dithiane 1-oxides and the parent 1,3-dithiane 1-oxide itself in high enantiomeric excesses.
High Stereocontrol in Aldol Reaction with Ketones: Enantioselective Synthesis of β-Hydroxy γ-Ketoesters by Ester Enolate Aldol Reactions with 2-Acyl-2-alkyl-1,3-dithiane 1-Oxides
作者:José L. García Ruano、David Barros、M. Carmen Maestro、Alexandra M. Z. Slawin、Philip C. Bulman Page
DOI:10.1021/jo000494i
日期:2000.9.1
2-acyl dithiane oxides, with lithiumenolates derived from several esters and lactones, proceeds with a high degree of stereocontrol at both carbonyl and enolate prochiral centers, the stereocontrol mainly determined by the configuration of the sulfoxide sulfur atom. The sense of induced stereochemistry observed for ester enolates is different from that seen for lactone enolates. Hydrolysis of the dithiane
Diastereoselective electrophilic amination of ketone enolates in 2-substituted 2-acyl-1,3-dithiane 1-oxides
作者:Philip C.Bulman Page、Steven M. Allin、Eric W. Collington、Robin A.E. Carr
DOI:10.1016/0040-4039(94)85237-5
日期:1994.4
Enolate anions derived from 2-substituted 2-acyl-1,3-dithiane 1-oxides react readily with the nitrogen electrophile di-tert-butyl azodicarboxylate (DBAD) to give α-aminoketones with good diastereoselectivity and in reasonable yields; in some cases diastereoselectivity appears sufficiently high that the minor isomer cannot be detected by 400 MHz 1H NMR spectroscopy.
由2-取代的2-酰基-1,3-二硫杂环丁烷1-氧化物衍生的乙醇酸根阴离子易于与亲电氮的偶氮二羧酸二叔丁酯(DBAD)反应生成具有良好非对映选择性和合理收率的α-氨基酮。在某些情况下,非对映选择性显得足够高,以至于较小的异构体无法通过400 MHz 1 H NMR光谱法检测到。
Enhanced diastereo and enantioselectivity in the formation of acyldithiolane sulphoxides by the asymmetric oxidation of their enolsilyl ethers
作者:M.Teresa Barros、Alcino J. Leitão、Christopher D. Maycock
DOI:10.1016/s0040-4039(97)01101-5
日期:1997.7
The sulphoxidation of the enol ethers of some acyldithiolanes using the Sharpless epoxidation reagents followed by fluorolysis results in better overall stereoselectivity than direct oxidation of the acyldithiolane thus providing a highly stereoselective route to acyldithiolane sulphoxides. Fluorolysis under acid conditions of non terminal enol ethers results in complete racemisation of the product. (C) 1997 Published by Elsevier Science Ltd.
BULMAN, PAGE PHILIP C.;PRODGER, JEREMY C., SYNLETT.,(1990) N, C. 460-462