6533b86efe1ef96bd12cb3a0

RESEARCH PRODUCT

SN1 Reactions in Supercritical Carbon Dioxide in the Presence of Alcohols: the Role of Preferential Solvation

Rossella MelloMaría Elena González NúñezRafael AcereteThais Delgado-abadGregorio AsensioJaime Martínez-ferrer

subject

chemistry.chemical_classificationSupercritical carbon dioxide010405 organic chemistryOrganic ChemistryInorganic chemistrySolvation010402 general chemistryRate-determining step01 natural sciencesBiochemistry0104 chemical sciencesReaccions químiqueschemistry.chemical_compoundSN1 reactionchemistryComputational chemistryAlcoholsCarbon dioxideLewis acids and basesMetal carbon dioxide complexPhysical and Theoretical ChemistryQuímica orgànicaAlkyl

description

Ethanol (3b) inhibits SN1 reactions of alkyl halides 1 in supercritical carbon dioxide (scCO2) and gives no ethers as products. The unexpected behaviour of alcohols 3 in the reaction of alkyl halides 1 with 1,3-dimethoxybenzene (2) in scCO2 under different conditions is rationalised in terms of Bronsted and Lewis acid–base equilibria of reagents, intermediates, additives and products in a singular solvent characterised by: (i) the strong quadrupole and Lewis acid character of carbon dioxide, which hinders SN2 paths by strongly solvating basic solutes; (ii) the weak Lewis base character of carbon dioxide, which prevents it from behaving as a proton sink; (iii) the compressible nature of scCO2, which enhances the impact of preferential solvation on carbon dioxide availability for the solvent-demanding rate determining step.

yearjournalcountryeditionlanguage
2016-06-16
10.1039/c6ob01097khttp://hdl.handle.net/10550/55079