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Reactions of biologically inspired hydride sources with B(C₆F₅)₃.

ABSTRACT: The combination of 1-benzyl-1,4-dihydropyridines with the strong Lewis acid, B(C₆F₅)₃, generates a stable pyridinium borohydride species in high yields (94%) in as little as 10 min. This use of biologically inspired hydride sources further builds on the recent work of new hydride donors in the formation of borohydrides. When functionalizing the dihydropyridine with an amide or carboxylic acid moiety, a disproportionation reaction composed of a series of protonation/reduction steps is observed upon the addition of B(C₆F₅)₃ As a result, one equivalent of dihydropyridine undergoes net hydrogenation, whereas the other is dehydrogenated yielding the pyridinium counterpart in a transfer hydrogenation-type mechanism.This article is part of the themed issue 'Frustrated Lewis pair chemistry'.

SUBMITTER: Wilkins LC

PROVIDER: S-EPMC5540842 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Reactions of biologically inspired hydride sources with B(C6F5)3.

Wilkins Lewis C LC Santi Nicolò N Luk Louis Y P LYP Melen Rebecca L RL

Philosophical transactions. Series A, Mathematical, physical, and engineering sciences 20170801 2101

The combination of 1-benzyl-1,4-dihydropyridines with the strong Lewis acid, B(C6F5)3, generates a stable pyridinium borohydride species in high yields (94%) in as little as 10 min. This use of biologically inspired hydride sources further builds on the recent work of new hydride donors in the formation of borohydrides. When functionalizing the dihydropyridine with an amide or carboxylic acid moiety, a disproportionation reaction composed of a series of protonati ...[more]

PMID: 28739967

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