Insertion of a Nontrigonal Phosphorus Ligand into a Transition Metal-Hydride: Direct Access to a Metallohydrophosphorane

Abstract

The synthesis and reactivity of an NPN-chelating ligand containing a nontrigonal phosphorous triamide center (L1 = P(N(o-N(2-pyridyl)C6H4)2) is reported. Metalation of L1 with RuCl2(PPh3)3 gives RuCl2(PPh3)(L1) (2). By contrast, metalation of L1 with RuHCl(CO)(PPh3)3 yields RuCl(CO)(PPh3)(L1H) (3), a chelated 10-P-5 ruthenahydridophosphorane, via net insertion into the Ru–H bond. Hydride abstraction from 3 with Ph3CPF6 gives [RuCl(CO)(PPh3)(L1)]PF6 (4); reaction of 4 with NaBH4 returns 3.

Recent developments in the chemistry of non-trigonal pnictogen pincer compounds: from bonding to catalysis

“…The arising biphilicity is shown upon complexation of the hydride complex [RuHCl(CO)(PPh 3 ) 3 ]. 69 Instead of coordination of the phosphorus ligand, the insertion product 8 was obtained (Scheme 5). Based on NMR measurements and DFT calculations, the reaction product is best described as an unprecedented metallohydrophosphorane complex.…”

Validating the Biphilic Hypothesis of Nontrigonal Phosphorus(III) Compounds

“…[9][10][11][12] Motivated by the perception that the restriction of phosphorus to local (pseudo)trigonal symmetry places an unnecessary check on the synthetic performance of s 3 -P compounds, [13][14][15][16][17][18][19][20][21][22][23] we have advanced the hypothesis that descent from trigonal symmetry should colocalize both donor and acceptor reactivity at as ingle s 3 -P site (i.e., biphilic [24] reactivity). Indeed, we have shown that nontrigonal s 3 -P compounds (see 1 and 2,F igure 1a)e volve to pentacoordinate phosphorus (s 5 -P) products through oxidative addition of EÀHb onds (E = OR, NHR, Ru), [25][26][27][28] in some cases reversibly. [29][30][31][32][33][34][35] Although applications of the biphilic character of nontrigonal s 3 -P compounds such as 1 and 2 have emerged in reactivity,adirect experimental demonstration of how the C 3v !C s structural deformation controls s 3 -P frontier orbital energies has not been previously presented.…”

Addition reactions of a phosphorus triamide to nitrosoarenes and acylpyridines

“…When redissolved in benzene, a 31 P NMR spectrum of the precipitate shows a single peak whose chemical shift (δ -19 ppm) suggests a pentacoordinate phosphorus environment. [28,34,35] By 1 H NMR spectroscopy, both the Nmethyl groups of the triamide ligand as well as the tert-butyl groups of the nitroso fragment are found to be inequivalent. Both the 31 P and 13 C NMR spectrum provide evidence for coupling between phosphorus and an ortho carbon atom of the nitrosoarene fragment with a magnitude ( 1 JC-P = 154 Hz)…”