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Structural Evidence for Pnictogen-Centered Lewis Acidity in Cationic Platinum-Stibine Complexes Featuring Pendent Amino or Ammonium Groups.

ABSTRACT: As part of our continuing interest in the chemistry of cationic antimony Lewis acids as ligands for late transition metals, we have now investigated the synthesis of platinum complexes featuring a triarylstibine ligand substituted by an o-[(dimethylamino)methyl]phenyl group referred to as Ar^N. More specifically, we describe the synthesis of the amino stibine ligand Ph₂SbAr^N (L) and its platinum dichloride complex [LPtCl]Cl which exists as a chloride salt and which shows weak coordination of the amino group to the antimony center. We also report the conversion of [LPtCl]Cl into a tricationic complex [LHPt(SMe₂)]³⁺ which has been isolated as a tris-triflate salt after reaction of [LPtCl]Cl with SMe₂, HOTf and AgOTf. Finally, we show that [LHPt(SMe₂)][OTf]₃ acts as a catalyst for the cyclization of 2-allyl-2-(2-propynyl)malonate.

SUBMITTER: Rodrigues RR

PROVIDER: S-EPMC8036533 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Lewis Acidic Boranes, Lewis Bases, and Equilibrium Constants: A Reliable Scaffold for a Quantitative Lewis Acidity/Basicity Scale.

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