Bykowski Darren, Wu Kou-Hui, Doyle Michael P
Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
J Am Chem Soc. 2006 Dec 20;128(50):16038-9. doi: 10.1021/ja066452e.
Vinylcarbenes are versatile synthetic intermediates, capable of asymmetric cyclopropanation and insertion into unactivated C-H bonds. The vinyldiazolactone precursor to the metal vinylcarbene possesses superior stability in comparison to previously known vinyldiazoacetates and, for the first time, allows the use of Z-vinylcarbenes in asymmetric C-H insertion and cyclopropanation reactions. Dirhodium azetidinone ligated compounds are optimal catalysts. Cyclopropanation coupled with the Cope rearrangement provides access to trans-3,4-disubstituted hydroazulenes.
乙烯基卡宾是通用的合成中间体,能够进行不对称环丙烷化反应以及插入未活化的碳氢键。与先前已知的乙烯基重氮乙酸酯相比,金属乙烯基卡宾的乙烯基重氮内酯前体具有更高的稳定性,并且首次使得Z-乙烯基卡宾能够用于不对称碳氢键插入反应和环丙烷化反应。二铑氮杂环丁酮连接的化合物是最佳催化剂。环丙烷化反应与科普重排反应相结合可得到反式-3,4-二取代氢化薁。