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Fast hydrazone reactants: electronic and acid/base effects strongly influence rate at biological pH.

ABSTRACT: Kinetics studies with structurally varied aldehydes and ketones in aqueous buffer at pH 7.4 reveal that carbonyl compounds with neighboring acid/base groups form hydrazones at accelerated rates. Similarly, tests of a hydrazine with a neighboring carboxylic acid group show that it also reacts at an accelerated rate. Rate constants for the fastest carbonyl/hydrazine combinations are 2-20 M(-1) s(-1), which is faster than recent strain-promoted cycloaddition reactions.

SUBMITTER: Kool ET

PROVIDER: S-EPMC3874453 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature

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Fast hydrazone reactants: electronic and acid/base effects strongly influence rate at biological pH.

Kool Eric T ET Park Do-Hyoung DH Crisalli Pete P

Journal of the American Chemical Society 20131113 47

Kinetics studies with structurally varied aldehydes and ketones in aqueous buffer at pH 7.4 reveal that carbonyl compounds with neighboring acid/base groups form hydrazones at accelerated rates. Similarly, tests of a hydrazine with a neighboring carboxylic acid group show that it also reacts at an accelerated rate. Rate constants for the fastest carbonyl/hydrazine combinations are 2-20 M(-1) s(-1), which is faster than recent strain-promoted cycloaddition reactions. ...[more]

PMID: 24224646

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