A new strategy for chemoselective O-acylation of β-mercapto alcohols via alkylsilyl and stannyl protection
摘要:
Chemoselective preparation of O-acylated derivatives from bis-protected mercapto alcohols was described. Trialkylsilyl and trialkylstannyl chloride are used to generate an intermediate with O- and S-protection. The intermediates from beta-mercapto alcohols are reactive toward acylating agents and selective to provide O-acylated derivatives. The present preparation involves the direct conversion of alcohol to the corresponding O-acylated compounds without deprotection. (C) 2008 Elsevier Ltd. All rights reserved.
Phthalimidosulfenyl chloride. Part 5. Reaction with enolizable carbonyl compounds and synthesis of functionalized thiones.
作者:Giuseppe Capozzi、Stefano Menichetti、Cristina Nativi、Alessandro Rosi、Giovanni Valle
DOI:10.1016/s0040-4020(01)82000-7
日期:1992.1
β-Ketothio derivatives 4, prepared by reaction of phthalimidosulphenyl chloride with enolizable carbonyl compounds, afford, in presence of pyridine, unstable functionalized thiones which can be trapped with 1,3-dienes to give the corresponding cycloaddition products8and9.
conversion are sulfur or mercaptan acids. An alternative way to convert H2S is still desirable. Herein, we have developed a green and mild method to convert H2S into mercaptan alcohols by the addition reaction with epoxide mediated in tertiary amine-functionalized protic ionicliquids (PILs). Reaction kinetics, substrate scope, and regeneration experiments have all been explored. Almost quantitative conversion
硫化氢(H 2 S)的资源化利用是能源化工领域的一个重要且具有发展前景的课题。我们集团以前通过 H 2 S 转化开发的产品是硫或硫醇酸。转化H 2 S的替代方法仍然是可取的。在此,我们开发了一种绿色温和的方法来转化 H 2在叔胺官能化的质子离子液体 (PIL) 中,通过与环氧化物的加成反应将 S 转化为硫醇。反应动力学、底物范围和再生实验都已被探索。在 30°C 下通过催化负载 PIL 实现了底物的几乎定量转化。水萃取用于从反应系统中回收催化剂。据信,优异的结果,加上其操作简单性和连续重复使用催化剂的能力,使这种新方法对环境无害且具有成本效益。H 2 S 资源方法的普遍性使其具有在工业规模上应用的潜力。
Reductions with Sulfurated Borohydrides. VII. Reactions with Epoxides
作者:J. M. Lalancette、A. Frêche
DOI:10.1139/v71-673
日期:1971.12.15
The reaction of NaBH2S3 with epoxides gives symmetrical bis-(2-hydroxyethyl) disulfides. The stereochemistry of the reaction is similar to the attack of H2S on the epoxides in basic solution. Substituted epoxides are opened from the less hindered side. The reaction proceeds with good yield and is general. An improved method of preparation of the 1,2-mercaptols is presented.
TBAF-catalyzed reaction of a range of substituted epoxides with hexamethyldisilathiane smoothly affords a direct and simple access to β-mercaptoalcohols in a highly regio- and stereoselective way.
syn -2,3-Disubstituted-2,3-dihydro-1,4-benzoxathiin rings: preparation from quinone ketals and 2-mercaptoethanols
作者:Peter G. Dormer、Amude M. Kassim、Johnnie L. Leazer、Fengrui Lang、Feng Xu、Kimberly A. Savary、Edward G. Corley、Lisa DiMichele、Jimmy O. DaSilva、Anthony O. King、David M. Tschaen、Robert D. Larsen
DOI:10.1016/j.tetlet.2004.05.047
日期:2004.7
A general method for the preparation of syn-2,3-disubstituted-2,3-dihydro-1,4-benzoxathiin rings from 2-mercaptoethanols and quinone ketals is presented. This ring system is produced by Michael addition of a 2-mercaptoethanol to a quinone ketal, followed by cyclization of the initial Michael adduct, and subsequent aromatization to afford a syn-2,3-disubstituted-1,4-benzoxathiin in fair to good chemical