Inorganic Chemistry, Vol.40, No.7, 1597-1605, 2001
Synthesis of beta-P,N aminophosphines and coordination chemistry to Pd-II. X-ray structures of [Pd Cl-2(Ph2PCH2CH(Ph)NHPh- kP,kN)] and [PdCl(eta(3)-C3H5) (Ph2PCH2CH(Ph)NHPh-kP)]
The reaction of the C=N bond in PhCH=NPh with the carbanionic species Ph2PCH2-, leading to the N-phenyl beta -aminsphosphine Ph2PCH2CH(Ph)NHPh, L-1, is described. This molecule reacts with different organic electrophiles to afford related compounds Ph2PCH2CH(Ph)NPhX (X = SiMe3, L-2; COPh, L-4), [Ph2MePCH2CH(Ph)NHPh](+)(I-), L-3, and [Ph2PCH2CH(Ph)N(Ph)CO](2), L-5, containing two amido and two phosphino functions. The coordination properties of L-1, L-2, and L-4 have been studied in palladium chemistry. The X-ray structure of [PdCl2(Ph2PCH2-CH(Ph)NHPh-kappaP,kappaN)I shows the bidentate coordination mode for the L-1 Ligand with equatorial C-Ph-N-Ph phenyl groups. [PdCl2(Ph2PCH2CH(Ph)NHPh-kappaP,kappaN)] crystallizes at 298 K in the space group P2(1)/n with cell parameters a = 10.689(2) Angstrom, b = 21.345(3) Angstrom, c = 12.282(2) Angstrom, beta = 90.294(1.2)degrees Z = 4, D-calcd = 1.526. The reaction between 2 equiv of L-1 and [PdCl(eta (3)-C3H5)](2) affords the [PdCl(eta (3)-C3H5)(Ph2PCH2CH(Ph)NHPh-kappaP)] complex in which an unexpected N-H . . . Cl intramolecular interaction has been observed by an X-ray diffraction analysis. [PdCl(eta (3)-C3H5)(Ph2PCH2CH(Ph)NHPh-kappaP)] crystallizes at 298 K in the monoclinic space group Cc with cell parameters a = 10.912(1) Angstrom, b = 17.194(2) Angstrom, c = 14.169(2) Angstrom, beta = 100.651(9)degrees Z = 4, D-calcd = 1.435. Neutral and cationic alkyl or allyl palladium chloride complexes containing L-1 are also reported as well as a neutral allyl palladium chloride complex containing L-4. Variable-temperature P-31{H-1} NMR studies on the allyl complexes show that the eta (3)/eta (1) allyl interconversion is enhanced by a positive charge and also by a N-H . . . Cl intramolecular interaction.