A computational study of the influence of methyl substituents on competitive ring closure to α- and β-lactones
| dc.cclicence | CC-BY | en |
| dc.contributor.author | Wilson, Philippe B. | en |
| dc.contributor.author | Williams, Ian H. | en |
| dc.date.acceptance | 2017-08-09 | en |
| dc.date.accessioned | 2017-08-22T09:49:30Z | |
| dc.date.available | 2017-08-22T09:49:30Z | |
| dc.date.issued | 2017-08-18 | |
| dc.description | Open Access article | en |
| dc.description.abstract | Ring-closure of substituted 2-chlorosuccinates to α- or β-lactones has been studied by means of MP2/6-311+G(d,p)//MP2/6-31+G(d) calculations in water treated as a polarised continuum (PCM) and in vacuum. Optimised geometries have been obtained for 2-chlorosuccinate and its 2-methyl, 3,3-dimethyl, and 2,3,3-trimethyl derivatives, along with the transition structures and products for intramolecular nucleophilic displacement leading to the 3- or 4-membered rings. Relative enthalpies and Gibbs free energies of activation and reaction are presented, along with key geometrical parameters, and changes in electrostatic-potential-derived atomic charges. The difference in free-energy barriers for α- and β-lactone formation from the 2-methyl substrate at 298 K is less than 1 kJ mol−1. Primary 14C kinetic isotope effects calculated for substitution at C2 are significantly smaller for α-lactone formation than for β, suggesting a possible way to distinguish between the competing pathways of reaction. The B3LYP method without dispersion corrections predicts the wrong relative stability order for methyl-substituted succinate dianions in PCM water. | en |
| dc.exception.reason | The output was published as gold open access | en |
| dc.funder | N/A | en |
| dc.identifier.citation | Wilson, P.B. and Williams, I.H. (2017) A computational study of the influence of methyl substituents on competitive ring closure to α- and β-lactones. Organic and Biomolecular Chemistry, 15, pp. 7235-7240 | en |
| dc.identifier.doi | https://doi.org/10.1039/C7OB01653K | |
| dc.identifier.uri | http://hdl.handle.net/2086/14427 | |
| dc.language.iso | en | en |
| dc.peerreviewed | Yes | en |
| dc.projectid | N/A | en |
| dc.publisher | Royal Society of Chemistry | en |
| dc.researchinstitute | Leicester Institute for Pharmaceutical Innovation - From Molecules to Practice (LIPI) | en |
| dc.subject | Chemistry | en |
| dc.subject | Computational Chemistry | en |
| dc.title | A computational study of the influence of methyl substituents on competitive ring closure to α- and β-lactones | en |
| dc.type | Article | en |