Chelated alkyl halide manganese complexes (η5:η1-C5H4CH2CH2X)Mn(CO)2 from photolysis of (η5-C5H4CH2CH2X)Mn(CO)3

Manganese tricarbonyl complexes (eta(5)-C5H4CH2CH2Br)Mn(CO), (3) and (eta(5)-C5H4CH2CH2I)Mn(CO)(3) (4), with an alkyl halide side chain attached to the cyclopentadienyl ligand, were synthesized as possible precursors to chelated alkyl halide manganese complexes. Photolysis of 3 or 4 in toluene, hexane of acetone-d(6) resulted in CO dissociation and intramolecular coordination of the alkyl halide to manganese to produce ( eta(5):eta(1)-C5H4CH2CH2Br)Mn(CO)(2) (5) and (eta(5):eta(1)-C5H4CH2CH2I)Mn(CO)(2) (6). Low temperature NMR and IR spectroscopy established the structures of 5 and 6. Photolysis of 3 in a glass matrix at 91 K demonstrated CO release from manganese. Low temperature NMR spectroscopy established that the coordinated alkyl halide complexes are stable to approximately - 20 degrees C. (C) 1998 Elsevier Science S.A. All rights reserved.