Mechanistic insight into the cleavage of an aromatic C-C bond by tungsten

摘要

The pathway for the cleavage of an aromatic C-C bond in quinoxaline by a tungsten(II) complex [W(PMe _3) _4(η ~2-CH _2PMe _2)H] is explored by performing detailed DFT calculations. The real active complex was found to be [W(PMe _3) _2(η ~2-CH _2PMe _2)H] rather than [W(PMe _3) _4]. The key step in the whole reaction is the reductive elimination of two hydrides that are located originally on quinoxaline (see scheme).