Catalyst-Free Conjugated Addition of Thiols to α,β-Unsaturated Carbonyl Compounds in Water
作者:Gopal L. Khatik、Raj Kumar、Asit K. Chakraborti
DOI:10.1021/ol060846t
日期:2006.5.1
[reaction: see text] Catalyst-free conjugateaddition of thiols to alpha,beta-unsaturated carbonylcompounds in water is reported. beta-Sulfido carbonylcompounds were formed at room temperature, in short times and with excellent chemoselectivity. Competitive dithiane/dithiolane formation, transesterification, and ester cleavage were not observed. Water played a dual role in simultaneously activating
Disclosed herein are novel analogs of cyclosporin, pharmaceutical compositions containing them, and methods for their use in the treatment of dry eye and other conditions.
CsF-Celite, an Efficient Solid State Reagent for the Syntheses of Thioesters and Thioethers
作者:Syed T. A. Shah、Khalid M. Khan、Hidayat Hussain、Safdar Hayat、Wolfgang Voelter
DOI:10.1007/s00706-005-0351-6
日期:2005.9
Coupling reactions of a number of aliphatic, aromatic, and heterocyclic compounds bearing an acidic hydrogen atom attached to sulfur, with alkyl, acyl, benzyl, or benzoyl halides in acetonitrile with cesium fluoride-Celite are described. This procedure is convenient, efficient, and practical for the preparation of thioethers and thioesters.
It was established that, in the presence of TiCl4, α,β-unsaturated carbonyl compounds react with ethanethiol at room temperature to afford the addition products, 3-ethylthiocarbonyl compounds, in good yields.
An alternative approach towards the syntheses of thioethers and thioesters using CsF–Celite in acetonitrile
作者:Syed Tasadaque Ali Shah、Khalid Mohammed Khan、Angelica Martinez Heinrich、Wolfgang Voelter
DOI:10.1016/s0040-4039(02)02028-2
日期:2002.11
It has been found that syntheses of thioethers and thioesters of aliphatic, aromatic and heterocyclic compounds, bearing thiol groups, can be accomplished with alkyl, acyl, benzyl or benzoyl halides in acetonitrile and cesium fluoride–Celite. In this manner, compounds like ethanethiol, 1-pentanethiol, thiophenol, 4-methoxythiophenol, 4-nitrothiophenol, and 2-mercaptobenzoxazole, 2-mercaptobenzothiazole