Reaction of Dialkyl-substituted Alkynes with Carbon Dioxide Catalyzed by Nickel(0) Complexes. Incorporation of Carbon Dioxide in Alkyne Dimers and Novel Cyclotrimerization of the Alkynes
作者:Yoshio Inoue、Yoshio Itoh、Haruo Kazama、Harukichi Hashimoto
DOI:10.1246/bcsj.53.3329
日期:1980.11
Ni(cod)2–Ph2P(CH2)4PPh2 system (cod=1,5-cyclooctadiene) catalyzed the reaction of 3-hexyne, for example, with CO2 to give a CO2 incorporated product, i.e., tetraethyl-2-pyrone, in a fairly good yield together with novel two cyclotrimers of the alkyne having cyclopentadiene structures, i.e., pentaethyl-5-(1-propenyl)-1,3-cyclopentadiene and pentaethyl-5-allyl-1,3-cyclopentadiene. The novel two cyclotrimers
Ni(cod)2–Ph2P(CH2)4PPh2 系统(cod=1,5-环辛二烯)催化 3-己炔与 CO2 的反应,得到包含 CO2 的产物,即四乙基-2-吡喃酮,在与具有环戊二烯结构的炔烃的新型两种环三聚体,即五乙基-5-(1-丙烯基)-1,3-环戊二烯和五乙基-5-烯丙基-1,3-环戊二烯一起,具有相当好的产率。在 CO2 下,Ni(cod)2–PPh3 系统选择性地形成了两种新型环三聚体,而在 N2 下,主要的三聚体是六乙苯。已提出用于吡喃酮形成的镍环戊二烯中间体。在阳离子镍氢化物络合物 [HNi(Ph2PCH2CH2PPh2)2]OCOCF3 催化的低聚反应中,还形成了新型的两个环三聚体,以及具有亚甲基环丁烯结构的新型二聚体,即 1,2,4-三乙基-3-亚乙基环丁烯。提到了加入的膦和活性氢化合物对新型低聚反应的影响。