Catalytic Carbonylation of β-Lactones to Succinic Anhydrides
摘要:
A well-defined, highly active and selective catalyst for the synthesis of succinic anhydrides from CO and beta-lactones is reported. At 200 psi of CO, the catalyst [(N,N'-bis(3,5-di-tert-butylsalicylidene)phenylenediamino)Al(THF)2][Co(CO)4] carbonylates beta-propiolactones to succinic anhydrides in high yield. (R)-beta-Butyrolactone is carbonylated to (S)-methylsuccinic anhydride with clean inversion of stereochemistry, while cis-2,3-dimethyl-beta-propiolactone yields exclusively trans-2,3-dimethylsuccinic anhydride. These data are consistent with a mechanism involving nucleophilic attack by [Co(CO)4]- on the beta carbon of the lactone, followed by CO insertion and anhydride formation.
Synthesis and inhibitory action on HMG-CoA synthase of racemic and optically active oxetan-2-ones (β-Lactones)
作者:Daniel Romo、Paul H.M. Harrison、Stephen I. Jenkins、R.William Riddoch、Kaapjoo Park、Hong Woon Yang、Cunxiang Zhao、Gerard D. Wright
DOI:10.1016/s0968-0896(98)00114-x
日期:1998.8
but variable enantioselectivity (22-85% ee). In in vitro assays using both native and recombinant HMG-CoA synthase from Saccharomyces cerevisiae, oxetan-2-ones mono-substituted at C4 with linear alkyl chains gave IC50s that decreased monotonically with chain length up to 10 carbons and then rose rapidly for longer chains. The transisomers of 3-methyl-4-alkyl-oxetan-2-ones showed a similar trend but had
Practical β-Lactone Synthesis: Epoxide Carbonylation at 1 atm
作者:John W. Kramer、Emil B. Lobkovsky、Geoffrey W. Coates
DOI:10.1021/ol061292x
日期:2006.8.1
text] A readily prepared bimetallic catalyst is capable of effecting epoxide carbonylation to produce beta-lactones at substantially lower CO pressures than previously reported catalyst systems. A functionally diverse array of beta-lactones is produced in excellent yields at CO pressures as low as 1 atm. This procedure allows for epoxide carbonylation on a multigram scale without the requirement of specialized
Chromium(III) Octaethylporphyrinato Tetracarbonylcobaltate: A Highly Active, Selective, and Versatile Catalyst for Epoxide Carbonylation
作者:Joseph A. R. Schmidt、Emil B. Lobkovsky、Geoffrey W. Coates
DOI:10.1021/ja051874u
日期:2005.8.1
of a tetracarbonylcobaltate anion and an octahedral chromium porphyrin complex axially ligated by two THF ligands. Regarding the carbonylation of epoxides to beta-lactones, catalyst 1 exhibits excellent turnover numbers (up to 10,000) and turnover frequencies (up to 1670 h(-1)), with regioselective carbonyl insertion occurring between the oxygen and the sterically less hindered carbon of the epoxide
Carbonylative Ring Expansion of Epoxides to β‐Lactones Using Inorganic Salt as Catalytic Species Precursor
作者:L. He、J.‐C. Yang、T.‐T. Song、Y. Liu、X.‐B. Lu
DOI:10.1002/ejic.202200496
日期:2022.12.16
cobalt bromide was developed for carbonylative ring expansion of epoxides to β-lactone products in moderate to excellent yields. This work also represents a rare example of epoxide carbonylationunderatmospheric CO pressure.
开发了一种从廉价、空气稳定的溴化钴原位生成低价钴物种的策略,用于环氧化物羰基化扩环生成 β-内酯产品,收率中等至极佳。这项工作也代表了大气 CO2 压力下环氧化物羰基化的罕见例子。