Synthesis of [6,n] cis-fused ring compounds via Cr-mediated dearomatisation–ring-closing metathesis
作者:E. Peter Kündig、Alejandro Bellido、Krishna P. Kaliappan、Andrew R. Pape、Sylvie Radix
DOI:10.1039/b513261d
日期:——
[6,7], [6,6] and [6,5] ring systems containing a cyclohexadiene ring unit, a cycloenone ring and a quaternary carbon at the ring junction were obtained in only two steps from [Cr(CO)3(eta6-p-methoxyphenyl oxazoline)]. The sequence proceeds via diastereoselective addition of three C-substituents across an arene double bond, followed by allylation and ring closing metathesis (RCM). RAMP-hydrazone and
仅在两个环中获得了顺式融合的[6,8],[6,7],[6,6]和[6,5]含环己二烯环单元,环烯酮环和季碳的环系统[Cr(CO)3(η6-对甲氧基苯基恶唑啉)]的步骤。该序列通过在芳烃双键上非对映选择性地添加三个C取代基,然后进行烯丙基化和闭环复分解(RCM)来进行。RAMP hydr和(R)-异丙基恶唑啉用作手性助剂,在除去助剂后,提供对映异构体高度富集的[6,7]顺式融合体系。