A catalyst-free, low-solvent method for the hydrophosphinylation of isocyanates and isothiocyanates is reported. A range of phosphorus nucleophiles including secondary phosphine oxides HP(O)R 2 (R = Ph, i Pr), phosphites HP(O)(OR) 2 (R = Me, Et), and methyl phenylphosphinate were tested. The procedure tolerated isocyanates and isothiocyanates featuring a wide range of substituents and, with use of 4 equiv of 2-methyltetrahydrofuran (2-MeTHF), solid substrates can be utilized. Twenty-five compounds were prepared with improved functional group tolerance compared to previous methods allowing access to new compounds (16 are novel). Facile scale up and simple reaction conditions make this a straightforward and practical methodology for obtaining phosphorus analogues of ureas and thioureas, which are challenging to synthesize by other methods.

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The effects of para -substitution on the structural and electronic properties of four series of two-coordinate m -terphenyl Group 12 complexes (R-Ar # ) 2 M (M = Zn, Cd, Hg; R = t -Bu 1 – 3 , SiMe 3 4 – 6 , Cl 7 – 9 , CF 3 10 – 12 , where R-Ar # = 2,6-{2,6-Xyl} 2 -4-R-C 6 H 2 and 2,6-Xyl = 2,6-Me 2 C 6 H 3 ) have been investigated. X-ray crystallography shows little structural variation across the series, with no significant change in the C–M–C bond distances and angles. However, considerable electronic differences are revealed by heteronuclear nuclear magnetic resonance (NMR) spectroscopy; a linear correlation is observed between the 113 Cd, 199 Hg, and 1 H (2,6-Xyl methyl protons) NMR chemical shifts of the para -substituted complexes and the Hammett constants for the R-substituents. Specifically, an upfield shift in the NMR signal is observed with increasingly electron-withdrawing R-substituents. Density functional theory (DFT) calculations are employed to attempt to rationalize these trends.

Ruthenium complexes of hemilabile phosphinocarboxamide ligands, and their use to form metallacycles using halide abstraction/deprotonation reactions are reported. Thus, [Ru(p-cym){PPh2C(=O)NHR}Cl2; R = iPr (1), Ph (2), p-tol (3)] and [Ru(p-cym){PPh2C(=O)N(R)C(=O)N(H)R}Cl2; R = Ph (4), p-tol (5)] were synthesized from [(p-cym)RuCl2]2 (p-cym = para-cymene) and phosphinocarboxamides or phosphinodicarboxamides, respectively. Single crystal X-ray diffraction measurements on 1–5 reveal coordination to ruthenium through the phosphorus donor, with an intramolecular hydrogen bond between the amine-bound proton and a metal-bound chloride. Six-membered metallacycles formed by halide abstraction/deprotonation of complexes 4 and 5 afforded [Ru(p-cym){κ2-P,N-PPh2C(=O)N(R)C(=O)NR}Cl] [R = Ph (6), p-tol (7)]. These species exist as a mixture of two rotational isomers in solution, as demonstrated by NMR spectroscopy.