Ligandgesteuerte Ringkontraktion von Nickela-Fuenf- in Vierringkomplexe-neuartige Startsysteme fuer die praeparative Chemie

Article abstract of DOI:10.1016/0022-328X(91)86320-P

Nickela-compounds with a five-membered ring, 4, are formed on Ni⁰ from CO2 and alkenes in the presence of the heterodifunctional ligand (cyclo-C6H11)2PCH2-CH2-2-pyridyl (2).A ring contraction occurs on addition of a promotor, such as BeCl2 or on heating.The greater reactivity of the nickela-complex with a four-membered ring, 6, can be used in the former reactions with CO2, CO or CH2=CH2.Such a sequence of reactions can be employed for the catalytic reaction of ethene with acrylic anilide on a (C6H11)3P/Ni⁰ system.