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Establishing the Role of Triflate Anions in H2 Activation by a Cationic Triorganotin(IV) Lewis Acid.

ABSTRACT: Cationic Lewis acids (LAs) are gaining interest as targets for frustrated Lewis pair (FLP)-mediated catalysis. Unlike neutral boranes, which are the most prevalent LAs for FLP hydrogenations, the Lewis acidity of cations can be tuned through modulation of the counteranion; however, detailed studies on such anion effects are currently lacking in the literature. Herein, we present experimental and computational studies which probe the mechanism of H2 activation using iPr3SnOTf (1-OTf) in conjunction with a coordinating (quinuclidine; qui) and noncoordinating (2,4,6-collidine; col) base and compare its reactivity with {iPr3Sn·base}{Al[OC(CF3)3]4} (base = qui/col) systems which lack a coordinating anion to investigate the active species responsible for H2 activation and hence resolve any mechanistic roles for OTf- in the iPr3SnOTf-mediated pathway.

SUBMITTER: Sapsford JS

PROVIDER: S-EPMC7469243 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Establishing the Role of Triflate Anions in H2 Activation by a Cationic Triorganotin(IV) Lewis Acid.

Sapsford Joshua S JS Csókás Dániel D Scott Daniel J DJ Turnell-Ritson Roland C RC Piascik Adam D AD Pápai Imre I Ashley Andrew E AE

ACS catalysis 20200608 14

Cationic Lewis acids (LAs) are gaining interest as targets for frustrated Lewis pair (FLP)-mediated catalysis. Unlike neutral boranes, which are the most prevalent LAs for FLP hydrogenations, the Lewis acidity of cations can be tuned through modulation of the counteranion; however, detailed studies on such anion effects are currently lacking in the literature. Herein, we present experimental and computational studies which probe the mechanism of H2 activation using iPr3</s ...[more]

PMID: 32905389

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