Development of Group 6 Dearomatization Agents

A series of complexes having the general formulas
[TpM(NO)(L)Br] and [TpmM(NO)(L)Br]BF4 (M = Mo or W
and L = a moderate σ-donor) have been prepared. Variations
in L provide access to M(I) complexes having a broad range
of electronic and steric properties. Reduction of a limited
number of these complexes in the presence of aromatic
molecules produces novel complexes with the general formula
[TpM(NO)(L)(η2-aromatic)]n+ (n = 0, 1).