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Group 9 and 10 Metal Complexes of an Ylide-Substituted Phosphine: Coordination versus Cyclometalation and Oxidative Addition.

ABSTRACT: Ylide-substituted phosphines (YPhos) have been shown to be excellent ligands for several transition metal catalyzed reactions. Investigations of the coordination behavior of the YPhos ligand YSPPh2 (1) [with YS = (Ph3P)(SO2Tol)C] toward group 9 and 10 metals revealed a surprisingly diverse coordination chemistry of the ligand. With Ni(CO)4, the formation of a di- as well as tricarbonyl complex is observed depending on the reaction conditions. In [( ?P,? 2 -benzene-1)Ni(CO)2] the phosphine ligand also coordinates via a phosphonium bound phenyl group to the metal leading to a unique nickel ? 2 -arene interaction, which can be viewed as an intermediate state toward P-C bond activation. Full cleavage of the P-C bond takes place with [Rh(COD)Cl]2 leading to a complex salt with [( ?P,?O-1)Rh(COD)]+ as cation and a dirhodium trichloride complex anion. Here, YSPPh2 underwent P-C bond cleavage to thus act as an anionic diphosphine ligand. In contrast, in [( ?P,?O-1)Rh(COD)]+ as well as [( ?P,?O-1)Rh(CO)Cl], formed from the reaction of 1 with [Rh(CO)2Cl]2, the YPhos ligand acts as bidentate ligand complexing the metal via the phosphine and sulfonyl moiety with an intact PPh3 unit. A further type of coordination is observed with [Ir(COD)Cl]2. Here, phosphine coordination is accompanied by C-H activation at one of the phosphonium bound phenyl groups leading to a cyclometalated complex.

SUBMITTER: Scherpf T

PROVIDER: S-EPMC6588272 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Group 9 and 10 Metal Complexes of an Ylide-Substituted Phosphine: Coordination versus Cyclometalation and Oxidative Addition.

Scherpf Thorsten T Rodstein Ilja I Paaßen Maurice M Gessner Viktoria H VH

Inorganic chemistry 20190605 12

Ylide-substituted phosphines (YPhos) have been shown to be excellent ligands for several transition metal catalyzed reactions. Investigations of the coordination behavior of the YPhos ligand YSPPh2 (1) [with YS = (Ph3P)(SO2Tol)C] toward group 9 and 10 metals revealed a surprisingly diverse coordination chemistry of the ligand. With Ni(CO)4, the formation of a di- as well as tricarbonyl complex is observed depending on the reaction ...[more]

PMID: 31185547

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Dataset Information

Group 9 and 10 Metal Complexes of an Ylide-Substituted Phosphine: Coordination versus Cyclometalation and Oxidative Addition.

Publications

Group 9 and 10 Metal Complexes of an Ylide-Substituted Phosphine: Coordination versus Cyclometalation and Oxidative Addition.

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