提出了阳离子Au I /手性磷酰胺配合物催化的1,6-烯炔的高度对映选择性氧化环丙烷化反应。该新方法可方便地获得具有三个高对映选择性(最高er 98:2)的稠密官能化双环[3.1.0]己烷,该己烷带有三个连续的季和叔立体异构中心。对照实验表明,反应中β-金乙烯基氧基喹啉鎓中间体的喹啉部分在过渡状态下通过过渡辅助作用在促进良好的对映选择性方面起着重要作用。
CO2 as a carboxylicacid is a significant reaction for C–C bond formation in organic synthesis. So far, besides C–H carboxylations using stoichiometric amounts of metals or organometallic reagents, great efforts have been devoted to develop new heterogeneous catalyst, while the catalytic performance of supportedmetalcatalysts is not satisfactory. Herein, a Schiff base-modified silver catalyst was developed
A highlyenantioselective oxidative cyclopropanation of 1,6‐enynes catalyzed by cationic AuI/chiral phophoramidite complexes is presented. The new method provides convenient access to densely functionalized bicyclo[3.1.0]hexanes bearing three contiguous quaternary and tertiary stereogeniccenters with high enantioselectivity (up to e.r. 98:2). Control experiments suggest that the quinoline moiety of
提出了阳离子Au I /手性磷酰胺配合物催化的1,6-烯炔的高度对映选择性氧化环丙烷化反应。该新方法可方便地获得具有三个高对映选择性(最高er 98:2)的稠密官能化双环[3.1.0]己烷,该己烷带有三个连续的季和叔立体异构中心。对照实验表明,反应中β-金乙烯基氧基喹啉鎓中间体的喹啉部分在过渡状态下通过过渡辅助作用在促进良好的对映选择性方面起着重要作用。
<i>cis</i>-1,2-Bis(diphenylphosphino)ethylene copper(<scp>i</scp>) catalyzed C–H activation and carboxylation of terminal alkynes
作者:Manoj Trivedi、Jacob R. Smreker、Gurmeet Singh、Abhinav Kumar、Nigam P. Rath
DOI:10.1039/c7nj03038j
日期:——
molar ratio in DCM–MeOH (50 : 50 V/V) under refluxing conditions gave two dimeric Cu(I) complexes, viz. [Cu2(μ-CN)2(κ2-P,P-dppet)2] (1) and [Cu2(μ2-SCN)2(κ2-P,P-dppet)2] (2). These complexes have been characterized by elemental analyses, IR, 1H and 31P NMR, and electronic absorption spectroscopies, and ESI-MS. The molecularstructure of 2 was confirmed by single crystal X-ray diffraction, which indicated