Intramolecular C-H Activation by Putative Terminal Two-Coordinate Manganese(III) Imido Intermediates: Hydrogen Abstraction from a Phenyl Group

Reactions of the Mn(I) inverted sandwich complex (eta(6)-C7H8){MnAr*-3,5-Pr-i(2)}(2) (Ar*-3,5-Pr-i(2) = C6H-2,6-(C6H2-2,4,6-Pr-i(3))(2)-3,5-Pr-i(2)) with bulky terphenyl azides afforded the dimeric Mn(II) amido/aryl complex {CH2C6H2-2-(C6H3-2-(N-(H)MnAr*-3,5-Pr-i(2))-3-(C6H2-2,4,6-Me-3))-3,5-Me-2}(2) (1) and the binuclear Mn(II) complex (mu,eta(1):eta(1)-NH-C6H3-2-(C6H2-3,5-'Bu-2)-6-(C6H3-3,5-'Bu-2)){MnAr*-3,5-Pr-i(2)}(2) (2). Complex 1 arises via methyl hydrogen abstraction by the nitrogen atom and dimerization via radical coupling with C-C bond formation. Complex 2 was formed by phenyl hydrogen abstraction by the imido nitrogen atom, followed by incorporation of a further MnAr*-3,5-Pr-i(2) unit. In addition, complex 2 features two different manganese environnments and is also the first structurally characterized heteroleptic two-coordinate diaryl Mn(II) species.