Synthesis of β-P,N Aminophosphines and Coordination Chemistry to PdII. X-ray Structures of [PdCl2(Ph2PCH2CH(Ph)NHPh-κPN)] and [PdCl(η3-C3H5)(Ph2PCH2CH(Ph)NHPh-κP)]

The reaction of the CN bond in PhCHNPh with the carbanionic species Ph2PCH2-, leading to the N-phenyl β-aminophosphine Ph2PCH2CH(Ph)NHPh, L1, is described. This molecule reacts with different organic electrophiles to afford related compounds Ph2PCH2CH(Ph)NPhX (X = SiMe3, L2; COPh, L4), [Ph2MePCH2CH(Ph)NHPh]+(I-), L3, and [Ph2PCH2CH(Ph)N(Ph)CO]2, L5, containing two amido and two phosphino functions. The coordination properties of L1, L2, and L4 have been studied in palladium chemistry. The X-ray structure of [PdCl2(Ph2PCH2CH(Ph)NHPh-κPN)] shows the bidentate coordination mode for the L1 ligand with equatorial CPh−NPh phenyl groups. [PdCl2(Ph2PCH2CH(Ph)NHPh-κPN)] crystallizes at 298 K in the space group P21/n with cell parameters a = 10.689(2) Å, b = 21.345(3) Å, c = 12.282(2) Å, β = 90.294(12)°, Z = 4, Dcalcd = 1.526. The reaction between 2 equiv of L1 and [PdCl(η3-C3H5)]2 affords the [PdCl(η3-C3H5)(Ph2PCH2CH(Ph)NHPh-κP)] complex in which an unexpected N−H···Cl intramolecular interaction has been observed by an X-ray diffraction analysis. [PdCl(η3-C3H5)(Ph2PCH2CH(Ph)NHPh-κP)] crystallizes at 298 K in the monoclinic space group Cc with cell parameters a = 10.912(1) Å, b = 17.194(2) Å, c = 14.169(2) Å, β = 100.651(9)°, Z = 4, Dcalcd = 1.435. Neutral and cationic alkyl or allyl palladium chloride complexes containing L1 are also reported as well as a neutral allyl palladium chloride complex containing L4. Variable-temperature 31P{1H} NMR studies on the allyl complexes show that the η31 allyl interconversion is enhanced by a positive charge and also by a N−H···Cl intramolecular interaction.