Nickel(0) induzierte und katalysierte CC-verknüpfungen von phenylisocyanat mit funktionalisierten alkenen
作者:Heinz Hoberg、Dieter Guhl
DOI:10.1016/0022-328x(89)85118-6
日期:1989.10
Monosubstituted alkenes RCHCH2 (R = OEt (Ia), SPh (Ib), CO2Me (Ic)) react with phenyl isocyanate on (Lig)Ni0 systems to form tricyclohexylphosphane-5-azanickelacyclopentan-4-one-derivatives (V). It is shown that the complexes V are intermediates in the catalytic CC coupling reaction. Further reactions by the system is dependent upon the nature of R. Thus when R = OEt (Ia) a β-elimination is induced
单取代的烯烃RCHCH 2(R = OET(Ia)中,SPh上(Ib)中,CO 2我(IC)),与异氰酸苯酯上(LIG)的Ni发生反应0系统形式tricyclohexylphosphane -5- azanickelacyclopentan -4-酮衍生物(V)。结果表明,络合物V是催化CC偶联反应的中间体。系统进一步的反应取决于R的性质。因此,当R = OEt(Ia)时,会诱导β消除,最终导致3-乙氧基丙烯酸苯胺(XIa),即1/1 CC的不饱和产物耦合。另一方面,当R = CO 2时在甲基(Ic)中进一步插入异氰酸酯,得到1,5-二苯基-2,6-二氧代-六氢嘧啶-4-酸甲酯(XII)。描述了特征,并讨论了反应机理。