SYNTHESIS AND CHARACTERIZATION OF ISOCYANIDE CONTAINING RHENIUM(III) COMPLEXES TRANS-[RECL3(CNR)(PPH(3))(2)] AND CRYSTAL-STRUCTURE OF TRANS-[RECL3(CN-T-C4H9)(PPH(3))(2)]

Isocyanide containing complexes trans-[ReCl3(CNR)(PPh(3))(3)] (3) (R = tert-C4H9 (3a), c-C6H11 (3b), C6H5 (3c), CH2C(O)OCH3 (3d), CH2CH2-(N- morpholinyl) (3e)) were obtained by reduction of trans-[Re(O)Cl-3(PPh( 3))(2)] with an excess of triphenylphosphane in the presence of the is ocyanide or by substitution of the acetonitrile ligand in trans-[ReCl3 (NCCH3)(PPh(3))(2)] by the isocyanide ligand. Generally, the substitut ion reaction starting with Re(III) gives a higher yield. The crystal s tructure of 3a has been determined by X-ray diffraction methods. 3a cr ystallizes with one molecule of CH2Cl2 per formula unit. Crystals of 3 a.CH2Cl2 are monoclinic, space group P2(1)/c with a = 12.868(3), b = 2 0.454(7), c = 16.378(9) Angstrom, beta = 104.71(4)degrees, Z = 4 and D -o = 1.58 g cm(-3). The structure was solved from 6190 diffraction dat a (F-0(2) greater than or equal to 3 sigma(F-0(2))] collected at -100( 2) degrees C and refined to R = 0.0429 (R(w) = 0.0727).