A total synthesis of tarchonanthuslactone exploiting N-pyrrole carbinols as efficient stereocontrolling elements

[reaction: see text] A short stereoselective total synthesis of the polyketide natural product, tarchonanthuslactone, has been achieved. The key sequence involves the first reported catalytic enantioselective reduction of an N-acyl pyrrole and subsequent use of this stereocenter in a diastereoselective reductive cascade. This proceeded with unprecedentedly high stereocontrol and offered an elegant method of generating the desired syn stereochemistry present in the final target in one step.     

Clean osmium-catalyzed asymmetric dihydroxylation of olefins in ionic liquids and supercritical CO2 product recovery

The combination of ionic liquids (ILs) as solvents in the asymmetric Sharpless dihydroxylation (AD) with the use of scCO(2) in the separation process allows a very simple, efficient, clean and robust system for the reuse of the AD catalytic system, which also does not need the use of organic solvents either for the reaction or for the separation of products and allows the isolation of the diol, in high yield and enantiomeric excess and basically without contamination with osmium.     

我国国家科学基金化学科学重大项目简介

稀土化学基础及应用研究——项目简介之九我国的稀土资源占世界首位,随着南(离子型矿)北(包头矿)两个稀土基地的建成,将对世界稀土市场产生举足轻重的影响.因此,研究稀土的分离、提取及开拓新应用领域,将对我国国民经济建设产生重要作用. 我国稀土研究已有近30多年的历史.目前,中科院、高等学校及产业部门已形成了一支很强的稀土研究和生产的队伍.若干领域已达到国际先进水平,如稀土萃取及工艺、稀土催     

3种全烷基化β—环糊精作毛细管气相色谱固定相的研究

作者合成了３种全烷基化β－环糊精，并将其涂溃石英毛细管色谱柱分离位置异构体和光学异构体得了良好的结果，其中全甲基化β－环糊精具有最好的选择性。