Reactions of (Ph)tBuP-P(SiMe3)Li·3THF with [(PNP)TiCl2] and [MeNacNacTiCl2·THF]: synthesis of first PNP titanium(iv) complex with the phosphanylphosphinidene ligand [(PNP)Ti(Cl){η2-P-P(Ph)tBu}]Electronic supplementary information (ESI) available. CCDC 1818921-1818924. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8dt01833b

Herein, the lithium derivative of diphosphane, (Ph) t BuP-P(SiMe 3 )Li ( 1 ), is isolated for the first time and investigated in reactions with β-diketiminate ( Me Nacnac − = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr 2 C 6 H 3 ) and PNP-pincer (PNP = N[2-PiPr 2 -4-methylphenyl] 2 ) Ti( iii ) complexes. The β-diketiminate titanium( iii ) complex containing the phosphanylphosphido ligand [ Me NacNacTi(Cl){η 2 -P(SiMe 3 )-P(Ph) t Bu}] ( 2 ) is prepared via the reaction of [ Me NacNacTiCl 2 ·THF] with (Ph) t BuP-P(SiMe 3 )Li in toluene solution with good yield and purity. The corresponding titanium( iv ) complex involving the phosphanylphosphinidene ligand [ Me NacNacTi(Cl){η 2 -P-P(Ph) t Bu}] ( 3 ) is synthesized via the oxidation of complex ( 2 ) with [ i Bu 3 PAgCl] 4 . Interestingly, an analogous PNP titanium( iv ) complex, [(PNP)Ti(Cl){η 2 -P-P(Ph) t Bu}] ( 4 ), is obtained in the reaction of [(PNP)TiCl 2 ] with (Ph) t BuP-P(SiMe 3 )Li in toluene solution and a 1 : 1 molar ratio instead of the expected titanium( iii ) complex with the phosphanylphosphido ligand. The solid-state structures of (Ph) t BuP-P(SiMe 3 )Li·3THF ( 1 ), [ Me NacNacTi(Cl){η 2 -P(SiMe 3 )-P(Ph) t Bu}] ( 2 ), [ Me NacNacTi(Cl){η 2 -P-P(Ph) t Bu}] ( 3 ) and [(PNP)Ti(Cl){η 2 -P-P(Ph) t Bu}] ( 4 ) are determined by single-crystal X-ray diffraction, which reveals that in all obtained complexes, both the phosphanylphosphinidene (Ph) t BuP-P and phosphanylphosphido (Ph) t BuP-P(SiMe 3 ) ligands are bidentate-coordinated to the metal center. We present the reactivity of [(PNP)TiCl 2 ] and [ Me NacNacTiCl 2 ·THF] towards the lithium derivative of diphosphane (Ph) t BuP-P(SiMe 3 )Li· n THF.