SYNTHESES AND CRYSTAL-STRUCTURES OF MOLYBDENUM(0) AND PALLADIUM(II) COMPLEXES OF 4-TERT-BUTYL-2-DIPHENYLPHOSPHINO-CYCLOHEXANONE N,N-DIMETHYLHYDRAZONE

Deprotonation of 4-tert-butyl-cyclohexanone N,N-dimethylhydrazone (1) with LiBu(n) at - 15 degrees C, followed by addition of PPh(2)Cl gave the corresponding phosphino dimethylhydrazone Z-PPh(2)C(10)H(17)=NNMe(2) (2), in which the PPh(2) group is in the axial position. 2 reacts with [Mo(CO)(4)(nbd)] (nbd=norbomadiene) to give the tetracarbonyl complex [Mo(CO)(4)(Z-PPh(2)C(10)H(17)=NNMe(2))] (3), containing a six-membered chelate ring and an axial PPh(2) group. Treatment of 2 with Na2PdCl4 or [PdCl2(NCPh)(2)] gave the dichloropalladium(II) complex [PdCl2(E-PPh(2)C(10)H(17)=NNMe(2))] (4), containing a five-membered chelate ring and an equatorial PPh(2) group due to isomerisations at C-2 and around C=N. Crystals of 3 are monoclinic, space group P2(1)/n with a=2083.4(4), b=1089.0(2), c=2521.9(5) pm, beta=98.82(2)degrees and 2=8, R=0.0263 for 6109 observed reflections with 1>2.0 sigma(I). Crystals of 4 are monoclinic, space group P2(1)/n with a=11.271(2), b=13.205(3), c=17.849(3) Angstrom, beta=104.83(1)degrees and Z=4, R(1)=0.0304 for 3994 observed reflections.