Rh(II)-Catalyzed Isomerizations of Cyclopropenes Evidence for Rh(II)-Complexed Vinylcarbene Intermediates
作者:Paul Müller、Nicole Pautex、Michael P. Doyle、Vahid Bagheri
DOI:10.1002/hlca.19900730513
日期:1990.8.8
The thermocatalytic rearrangements of cyclopropenes 1-4 have been investigated in the presence of Rh(IT) perfiuorobutyrate. 1, 2, 3-Triphenylcyclopropene (1a) undergoes rearrangement lo diphenylindene 5a or, with alkoxycyclopropene derivatives, to α, β-unsaturated ketone 6. Furan formation occurs with 2, 3-diphenylcyclo-propenecarboxylate 2, but the diethyl counterpart 3 rearranges to dienoate 8. 2-
已经在存在全氟丁酸Rh(IT)的情况下研究了环丙烯1-4的热催化重排。1,2,3-3-三苯基环丙烯(1a)经过重排二苯基茚5a或与烷氧基环丙烯衍生物重排成α,β-不饱和酮6。呋喃形成发生在2,2,3-二苯基环丙烯羧酸2,但二乙基对应物3重排为二烯酸8。2-烷基环丙烯羧酸酯4得到(E)-亚甲基环戊烷衍生物9作为唯一可分离的产品,产量约为 35%。提出了一种机制,该机制包括向Rh-络合的乙烯基碳烯的区域和立体特异性的环丙烯环开环,并将后者插入CH键中得到9。类似的机制应说明1到3的重排乘积。