Complexes of tert-butyl diphenylphosphinomethyl ketone N-phenylhydrazone, Z-PPh(2)CH(2)C(Bu(t))=NNHPh, with molybdenum, palladium or platinum: Crystal structure of cis-[PdCl2{Z-PPh(2)CH(2)C(Bu(t))=NNHPh}(2)]

tert-Butyl diphenylphosphinomethyl ketone N-phenylhydrazone, Z-PPh(2)CH(2)C(Bu(t))=NNHPh (1), was prepared by heating the phosphino N,N-dimethylhydrazone, ZPPh(2)CH(2)C(Bu(t))=NNMe(2) with PhNHNH(2) in ethanol in the presence of acetic acid as catalyst. This phosphine was converted into the corresponding phosphine oxide 2a and phosphine sulfide 2b. Treatment of [Mo(CO)(4)(nbd)] (nbd=norbomadiene) with 1 equiv. of 1 gave the tetracarbonylmolybdenum(0) complex [Mo(CO)(4){PPh(2)CH(2)C(Bu(t))=NNHPh}] (3) in which 1 is bidentate; [Mo(CO)(4)(nbd)] with 2 equiv. of 1 gave the bis(phosphine)molybdenum(0) complex cis-[Mo(CO)(4){PPh(2)CH(2)C(Bu(t))=NNHPh}(2)] (4) in which 1 is monodentate through P. Treatment of [PdCl2(NCPh)(2)] or [PtCl2(cod)] (cod=cycloocta-1,5-diene) with 2 equiv. of 1 gave the complexes cis-[MCl(2){PPh(2)CH(2)C(Bu(t))=NNHPh}(2)] (M=Pd (5a), Pt (5b)). The crystal structure of 5a was determined. Treatment of [PtCl2(NCMe)(2)] with 2 equiv. of the phosphine 1 gave trans-[PtCl2{PPh(2)CH(2)C(Bu(t))=NNHPh}(2)] (5c). Dehydrochlorination of the platinum(II) dichloride 5b or 5c with Et(3)N gave the neutral cis-[Pt{PPh(2)CH(2)C(Bu(t))=NNPh}(2)] (6), containing two six-membered chelate rings. Treatment of the pi-2-methylallyl complex [{(eta(3)-2-MeC(3)H(4))PdCl}(2)] with 2 equiv. of the phosphine 1 gave the neutral complex [(eta(3)-2-MeC(3)H(4))PdCl{PPh(2)CH(2)C(Bu(t))=NNHPh}] (7) in which 1 is monodentate through P. Dehydrochlorination of 7 with aqueous NaOH solution gave the pi-methylallylpalladium(II) chelate complex [(eta(3)-2-MeC(3)H(4))Pd{PPh(2)CH(2)C(Bu(t))=NNPh}] (8) containing an amide-palladium bond. Treatment of 1 with LiBu(n) followed by PPh(2)Cl gave the diphosphine Z-PPh(2)CH(2)C(Bu(t))=NN(Ph)PPh(2) (9) which with 0.5 equiv. of [{(eta(3)-2-MeC(3)H(4))PdCl}(2)] followed by NH4PF3 gave the pi-methylallylpalladium(II) PF6 salt [(eta(3)-2-MeC(3)H(4))Pd-{PPh(2)CH(2)C(Bu(t))=NN(Ph)PPh(2)}]PF6 (10). Crystals of 5a are monoclinic, space group P2(1)/c, with a=12.900(2), b=40.083(6), c=10.8779(11) Angstrom, beta=111.891(7)degrees and Z=4, final R=0.0535 for 7558 observed reflections with F>4.0 sigma(F).