Unexpected Reaction of (trindane)Mn(CO)3 +BF4 - with Potassium tert-Butoxide: Three C−H Insertions and a Haptotropic Shift

(η6-trindane)Mn(CO)3 +BF4 - (1) reacts with ButOK in THF in the presence of alkyl halides (CH3I, CH2CHCH2Br, CH2Cl2) to yield the corresponding (η6-C15H18)Mn(CO)2X, where X = I, Br, Cl. In contrast, 1 and ButOK react, in the presence of a donor ligand, to generate (η5-C15H15)Mn(CO)2L, where L = CO, P(OMe)3, PPh3, in which the metal has migrated from the central ring onto a peripheral ring that has lost three hydrogens; (η6-indane)Mn(CO)3 +BF4 - behaves similarly. A mechanism is proposed in which the initially formed (η6-trindane)Mn(CO)2CO2But suffers loss of CO2 and isobutene to yield the hydride (η6-trindane)Mn(CO)2H, which in turn undergoes three successive C−H insertions with concomitant loss of 2 mol of dihydrogen.