SYNTHESES OF METAL-CARBONYLS .23. CRYSTAL -STRUCTURE AND REACTIVITY OF HEPTAMETHYLINDENYL CARBONYL METAL-COMPLEXES

Reaction of heptamethylindene (C-9(CH3)(7), 1) with Re-2(CO)(10) yield s [eta(5)-C-9(CH3)(7)]Re(CO)(3) (2), which reacts with NO+BF4- to form the cationic complex [{eta(5)-C-9(CH3)(7)}Re(CO)(2)NO]+BF4- (3). Irra diation of 2 with UV light in che presence of triethyl phosphite leads to formation of [eta(5)-C-9(CH3)(7)]Re(CO)(2)[P(OC2H5)(3)] (4). Alkyl ation of (CH3)(3)SnCl with IndLi gives [eta(1)-C-9(CH3)(7)]Sn(CH3)(3) (5). All compounds were characterized by spectroscopic methods. The m olecular structures of 3 and 5 were determined by single crystal X-ray diffraction (3: P2(1)/n (14), a=1497.7(4) pm, b=879.0(2) pm, c=1609.0 (4) pm and beta=110.99(2)degrees, R-1=0.038, wR(2)=0.080; 5: P2(1)/n ( 14), a=726.1(1) pm, b=2930.7(3) pm, c=930.0(1) pm and beta=112.834(5)d egrees, R-1=0.044, R-w=0.048). Complexes 2-4 exhibit a piano stool con figuration with a eta(5)-coordinated permethyl-indenyl ligand (Ind). Compound 5 displays a eta(1)-coordination of the Ind ligand. Temperat ure enhancement causes a hapticity change, as observed by NMR spectros copy.