Atom economical synthesis of di- and trithiocarbonates by the lithium tert-butoxide catalyzed addition of carbon disulfide to epoxides and thiiranes
作者:J. Diebler、A. Spannenberg、T. Werner
DOI:10.1039/c6ob01081d
日期:——
selective catalyst for this reaction. The influence of different reaction parameters as well as the substrate scope under optimized reactionconditions has been studied. Terminal and highly substituted epoxides as well as thiiranes were converted. In total 28 products were prepared and isolated in yields up to 95%. Notably, the reactions were performed undermildconditions without additional solvents
研究了碱金属醇盐作为将CS 2加到环氧化物中的催化剂。几种市售醇盐的筛选显示叔丁醇锂是该反应的活性和选择性催化剂。研究了在最佳反应条件下不同反应参数以及底物范围的影响。末端和高度取代的环氧化物以及硫烷被转化。总共制备并分离了28种产品,收率高达95%。值得注意的是,该反应在温和的条件下进行,无需额外的溶剂。已经研究了反应的区域和立体选择性,例如,通过转化(R)-苯乙烯和(R)-环氧丙烷。此外,通过13 C NMR监测测试反应,并给出了末端和内部环氧化物转化的合理机理。该提议与观察到的反应的区域选择性和立体选择性一致。
Access to nonisocyanate poly(thio)urethanes: A comparative study
This article describes the synthesis of new cyclic compounds able to react with amines to get nonisocyanate polyurethanes (NIPUs). The contribution of the most studied five‐membered cyclic carbonate was compared to five‐membered cyclic dithiocarbonate analogous and to a six‐membered cyclic carbonate. Difunctional reactive species were obtained by a simple substitution reaction or an efficient thiol–ene
Selectively synthesis of cyclic di- and trithiocarbonates by N -heterocyclic carbene/LiCl(Br) catalyzed addition of carbon disulfide to epoxides
作者:Congmin Mei、Xu Li、Lihuai Liu、Changsheng Cao、Guangsheng Pang、Yanhui Shi
DOI:10.1016/j.tet.2017.08.009
日期:2017.9
Carbon disulfide is an abundant, inexpensive and readily available material. One of the main challenges in the reaction of epoxides with CS2 is to control the chemoselectivity as a variety of compounds would be formed in the reaction. A simple and convenient method toward selectively synthesis of oxathiolane and trithiocarbonate from epoxides with CS2 catalyzed by NHC/LiCl(Br) under the neat conditions
An efficient one-pot synthesis of functionalized 1,3--oxathiolane-2-thiones is described via reaction of carbon disulfide with oxiranes in the presence of sodium hydride (10 mol%) and methanol.