摘要:
The catalytic activity of Co-2(CO)(6)L-2 complexes (L = carbon monoxide, phosphines) has been tested in the oligomerization of aldehydes under the conditions adopted for hydroformylation of olefins. The influence of the type of substrate, phosphinic ligand and reaction temperature has been investigated. The products formed are beta-hydroxyaldehydes, alpha,beta-unsaturated aldehydes and beta-hydroxyesters, Very poor catalytic activity was shown by cobalt complexes in the oligomerization of ketones. The role of cobalt carbonyI complexes in the aldehyde oligomerization has been rationalized by a mechanism, in which acylcobalt intermediates are involved. (C) 1998 Elsevier Science B.V. All rights reserved.