N-(2,6-Dimethylphenyl)diphenylphosphinamine chalcogenides (S, Se) and a zirconium complex possessing phosphanylamide in the coordination sphere

Abstract

We report the syntheses of N-(2,6-dimethylphenyl)-P,P-diphenylphosphinothioic amide Ph2P(S)NH-(2,6-Me2C6H3)] (2) and N-(2,6-dimethylphenyl)-P,P-diphenylphosphinoselenoic amide Ph2P(Se)NH-(2,6-Me2C6H3)] (3) by the reaction of N-(2,6-dimethylphenyl)-P,P-diphenylphosphinamine [Ph2PNH-(2,6-Me2C6H3)] (1) with elemental sulphur and selenium respectively. When the phosphinamine compound 1 was treated with n-BuLi and subsequently with zirconocenedichloride in an equimolar ratio, the corresponding zirconium complex [{η5-Cp2ZrCl(η2-N(2,6-Me2C6H3)PPh2}] (5) was obtained in good yield. The solid state structures of all the compounds were established by single crystal X-ray diffraction analysis. In zirconium complex 5, a highly strained three membered metallacycle was observed. In addition, the solid state structure of [Ph2P(O)NH(2,6-Me2C6H3)] (4) was also determined. In the solid state structure, compound 4 shows extensive intermolecular hydrogen bonding through oxygen atoms, whereas a lesser extent of intermolecular hydrogen bonding was noted in compound 2, due to the presence of the less electronegative sulphur atom.