Synthesis of Medium-Sized Carbocycles by Gallium-Catalyzed Tandem Carbonyl–Olefin Metathesis/Transfer Hydrogenation
作者:Alexandre Djurovic、Marie Vayer、Zhilong Li、Regis Guillot、Jean-Pierre Baltaze、Vincent Gandon、Christophe Bour
DOI:10.1021/acs.orglett.9b03240
日期:2019.10.4
catalytic tandem process involving a ring-closing carbonyl-olefin metathesis and a transfer hydrogenation are described. 1,4-Cyclohexadiene has been used as an H2 surrogate to reduce the cyclic alkenes formed after the metathesis step. The same cationic gallium(III) complex, [IPr·GaCl2][SbF6], performs the two steps with functional group tolerance. This stereoselective reaction leads to 1,2-cis-disubstituted
描述了催化串联过程的第一个例子,该过程涉及闭环羰基烯烃复分解和转移氢化。1,4-环己二烯已被用作H 2的替代品,以还原易位步骤后形成的环状烯烃。相同的阳离子镓(III)络合物[IPr·GaCl 2 ] [SbF 6 ]执行具有官能团耐受性的两个步骤。该立体选择性反应导致1,2-顺式-二取代的环戊烷和各种环己烷。DFT计算支持一种意想不到的机制,该机制涉及通过超亲电子的镓(III)二聚体活化1,4-环己二烯。