1,3,5-trimethyl-1,3,5-triazacyclohexane tricarbonyl complexes of Mo and W as sources of the fac-M(CO)3 fragment.: Mild syntheses of fac-[M(CO)3(CH3CN)3] (M = Mo, W), [W(CO)3(PR3)3], [W(CO)(alkyne)3] and [W(CO)3(π-arene)] complexes

The 1,3,5-trimethyl-1,3,5-triazacyclohexane (Me(3)tach) group in [M(CO)(3)(Me(3)tach)] complexes (M=Mo, W) is easily displaced by a variety of ligands under mild conditions. The lability of the Me(3)tach ligand allows the [M(CO)(3)(Me(3)tach)] complexes to be used as synthetic intermediates in convenient syntheses of products such as fac-[M(CO)(3)(CH3CN)(3)] (M=Mo,W), [W(CO)(alkyne)(3)], [W(CO)(3)(PR3)(2)] and [W(CO)(3)(eta(6)-arene)] complexes. An improved synthesis of [W(CO)(3)(Me(3)tach)] from [W(CO)(6)] and Me(3)tach is described. (C) 1998 Elsevier Science S.A. All rights reserved.