Late Transition‐Metal Complexes of 2‐Ph ₂ PC ₆ H ₄ NHC(O)CH ₂ NHCO ₂ Bz: Observation of Three Distinct Ligation Modes (κ ¹ ‐P,κ ² ‐P/N and κ ³ ‐P/N/N′)

The one-step synthesis of the amide-functionalised tertiary phosphane 2-Ph 2 PC 6 H 4 NHC(0)CH 2 NHCO 2 Bz (Bz = CH 2 Ph), 2-HH, by condensation of the known aminophosphane, 2-Ph 2 PC 6 H 4 (NH 2 ) (1), with N-(benzyloxycarbonyl)-glycine and dicyclohexylcarbodiimide (DCC) in THF at room temperature is reported. The new ligand 2·HH displays various coordination modes when complexed to a range of late transition-metal precursors. Hence κ 1 -P-coordination for 2·HH is observed in the complexes ClAu(2·HH) (3), MCl 2 (η 5 -Cp*)(2·HH) (M = Rh 4; Ir 5), RuCl 2 (η-p-cymene)(2·HH) (6), Pd(κ 2 -CN-C 12 H 12 N)Cl(2·HH) (7) and MCl 2 (2·HH) 2 (M = Pd 8; Pt 9). Treatment of 8 or 9 with tBuOK in CH 3 OH gave the bis-κ 2 -P/N-chelate complexes cis-M{2-Ph2PC6H4NC(O)CH2-NHCO 2 Bz} 2 (M = Pt 10; Pd 11) in which both monoanionic ligands 2·H - are disposed in a cis geometry. The related nickel(II) complex cis-Ni{2-Ph 2 PC 6 H 4 NC(0)CH 2 NHCO 2 -Bz} 2 (12) was prepared from NiCl 2 ·6H 2 O, 2 equiv. of 2·HH and tBuOK in refluxing CH 3 OH. Reaction of the piano-stool complex 5 with tBuOK in CH 3 OH gave the chiral-at-metal complex Ir(η 5 -Cp*){2-Ph 2 PC 6 H 4 NC(O)CH 2 NCO 2 Bz} (14), present in solution as two diastereomers. A single-crystal X-ray diffraction study of 14 confirmed the κ 3 -P/N/N'-tridentate coordination mode. Under similar conditions the chiral-at-metal ruthenium(II) complex Ru(η 6 -p-cymene){2-Ph 2 PC 6 H 4 NC(0)CH 2 NCO 2 Bz} (15) was prepared in which 2 2- functions efficiently as a dianionic tridentate ligand. All new compounds have been characterised by multinuclear NMR [ 31 P{ 1 H}, 1 H], FT-IR, EI-MS, ES-MS and microanalysis. Furthermore, the X-ray structures of ten compounds have been determined and reveal, in the majority of cases, a strong propensity for the -NHC(O)CH 2 NHCO 2 Bz group to engage in N-H···N, N-H···O and N-H···Cl hydrogen bonding.