En route to phosphonato iridium(i) complexes: the decisive effect of an intramolecular hydrogen bond12. Issue 3 (8th December 2015)

• Record Type: Journal Article
• Authors: Passarelli, Vincenzo; Pérez-Torrente, Jesús J.; Oro, Luis A.
• Is Part Of: Dalton transactions. Volume 45:Issue 3(2016)
• Page Start: 951
• Page End: 962
• Publication Date: 2015-12-08
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c5dt04038h
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The decisive role of an intramolecular NH⋯OP hydrogen bond in the formation of a dimethyl phosphonato iridium(i ) complex is shown. Abstract : Pentacoordinated iridium(i ) complexes of formula IrCl(SiNP)(tfbb) (1 ) and IrCl(HNP)2 (tfbb) (2 ) (SiNP = SiMe2 {N(4-C6 H4 CH3 )PPh2 }2 ; HNP = NH(4-C6 H4 CH3 )PPh2 ) have been prepared and fully characterised. Both feature a distorted square pyramidal coordination polyhedron at the metal centre in the solid state and are fluxional in solution. Their reaction with trimethyl phosphite yields the derivatives [Ir(SiNP){P(OMe)3 }(tfbb)]Cl ([3 ]Cl) and Ir{PO(OMe)2 }(HNP)2 (tfbb) (4 ). The course of the reaction between IrCl(HNP)2 (tfbb) (2 ) and trimethyl phosphite was elucidated by NMR spectroscopy and DFT calculations, showing that the intermediate [Ir(HNP)2 {P(OMe)3 }(tfbb)] + (5 + ) forms and further reacts with the chloride anion yielding the phosphonato derivative4 and methyl chloride. The decisive role of the N–H group in the formation of the phosphonato ligand has been established by IR and NMR spectroscopic measurements and by DFT calculations.