Triphenylphosphine-cyclometallated iridium(III) pyrimidine complexes: Synthesis, crystal structures and application in α-alkylation of ketones with alcohols

Two triphenylphosphine (PPh3)-cyclometallated iridium(III) pyrimidine complexes Ir(NDMP)2PPh3Cl 1 and Ir(NDMP)(PPh3)2Cl22 (NDMP = 2-(2-naphthyl)-4,6- dimethyl-pyrimidine) were synthesized and characterized by NMR, IR, ESI-MS, and elemental analysis. Additionally, their detailed structures have been determined by X-ray single-crystal diffraction. The complex 1 was a PPh3-biscyclometalated Ir(III) complex, while 2 was a PPh3-monocyclometalated Ir(III) complex. These complexes were found to be efficient catalysts for α-alkylation of ketones with alcohols.

Graphical abstractTwo PPh3-cyclometallated Ir(III) pyrimidine complexes Ir(NDMP)2PPh3Cl 1 and Ir(NDMP)(PPh3)2Cl22 (NDMP = 2-(2-naphthyl)-4,6-dimethylpyrimidine) were synthesized and characterized. The complex 1 was a PPh3-biscyclometalated Ir(III) complex, while 2 was a PPh3-monocyclometalated Ir(III) complex. These complexes were efficient catalysts for α-alkylation of ketones with alcohols.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► PPh3-cyclometalated Ir(III) complexes 1–2 are efficient catalysts for α-alkylation of ketones with alcohols. ► X-ray structures of two PPh3-cyclometalated Ir(III) complexes 1–2. ► PPh3-biscyclometalated Ir(III) complex 1 and PPh3-monocyclometalated Ir(III) complex 2 were synthesized.