Linear alpha-olefins obtained with palladium(II) complexes bearing a partially oxidized tetraphosphane

The coordination of Pd(II) to the 1,3-trans- and 2,3- trans-dioxides and the trioxide of cis,trans,cis-1,2,3,4-tetrakis- (diphenylphosphino)cyclobutane gave two dinuclear Pd(II) complexes, which are structural isomers, and a mononuclear complex, respectively. The latter complexes proved to be suitable precatalysts for the oligomerization of ethylene to linear ?-olefins (98% selectivity). The different catalytic activity of the structural isomers was shown to depend on the dynamic behavior of the molecular structure.