Ni0-induzierte CC-Verknuepfungen von Phenylisocyanat mit cyclischen, fuenfgliedrigen Alkenen, katalytische Herstellung von β,γ-ungesaettigten Carbonsaeureaniliden

Article abstract of DOI:10.1016/0022-328X(91)86057-W

Cycloalkenes with a five-membered cyclic system like bicyclo<3.3.0>octene-2 (1a), 2,3-dihydrofuran (1b) and 2,5-dihydrofuran (1c) react with phenylisocyanate on a (Lig)Ni⁰-system (Lig = tricyclohexylphosphane) to form tricyclohexylphosphane-5-azanickelacyclopentan-4-one derivatives by oxidative 1 : 1 CC-coupling.It has been shown, that these complexes are intermediates of catalytic reactions in which only H-abstraction in β'-position outside the nickelaheterocyclic system takes place because of cis-configuration of this bi- or tricyclic metalla complexes.In this way β,γ-unsaturated carboxylic acid-anilides are obtained with high selectivity.Catalytic CC-coupling does not occur if the β'-position is occupied by an oxygen atom as shown in the metallacycle formed from 2,3-dihydrofuran, phenylisocyanate and (Lig)Ni⁰.