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Understanding thio-effects in simple phosphoryl systems: role of solvent effects and nucleophile charge.

ABSTRACT: Recent experimental work (J. Org. Chem., 2012, 77, 5829) demonstrated pronounced differences in measured thio-effects for the hydrolysis of (thio)phosphodichloridates by water and hydroxide nucleophiles. In the present work, we have performed detailed quantum chemical calculations of these reactions, with the aim of rationalizing the molecular bases for this discrimination. The calculations highlight the interplay between nucleophile charge and transition state solvation in SN2(P) mechanisms as the basis of these differences, rather than a change in mechanism.

SUBMITTER: Carvalho AT

PROVIDER: S-EPMC4425225 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Understanding thio-effects in simple phosphoryl systems: role of solvent effects and nucleophile charge.

Carvalho Alexandra T P AT O'Donoghue AnnMarie C AC Hodgson David R W DR Kamerlin Shina C L SC

Organic & biomolecular chemistry 20150501 19

Recent experimental work (J. Org. Chem., 2012, 77, 5829) demonstrated pronounced differences in measured thio-effects for the hydrolysis of (thio)phosphodichloridates by water and hydroxide nucleophiles. In the present work, we have performed detailed quantum chemical calculations of these reactions, with the aim of rationalizing the molecular bases for this discrimination. The calculations highlight the interplay between nucleophile charge and transition state solvation in SN2(P) mechanisms as ...[more]

PMID: 25797408

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