Allenes bearing a nucleophilic group cyclize on treatment with acyltetracarbonyl cobalt complexes in the presence of mild bases. Various nucleophilic groups and cobalt complexes can be used to give highly functionalized pyrrolidines, cyclopentanes and tetrahydrofurans. Disubstituted allenes may be used in the reaction. 1,3-disubstituted allenes give products with high stereoselectivity.
Allenes bearing a nucleophilic group cyclize on treatment with acyltetracarbonyl cobalt complexes in the presence of mild bases. Various nucleophilic groups and cobalt complexes can be used to give highly functionalized pyrrolidines, cyclopentanes and tetrahydrofurans. Disubstituted allenes may be used in the reaction. 1,3-disubstituted allenes give products with high stereoselectivity.