Effects of a Side Chain Aromatic Ring on the Reactivity of Copper(I) Complexes with Dioxygen.

Stabilization of the bis(μ-oxo)dicopper(III) intermediate is achieved by using a bidentate N-donor ligand with pendent indole rings: N,N-bis[(3-indolyl)methyl]-N-[(2'-pyridyl)methyl]amine (BIP). The intermediate decomposes to give products arising from N-dealkylation and a product with a spiro ring composed of two indole rings. This latter product probably results from a radical-coupling reaction.