Kinetic Studies that Evaluate the Solvolytic Mechanisms of Allyl and Vinyl Chloroformate Esters

• Main Authors: Malcolm J. D'Souza, Aaron F. Givens, Peter A. Lorchak, Abigail E. Greenwood, Stacey L. Gottschall, Shannon E. Carter, Dennis N. Kevill
• Format: Article
• Language: English
• Published: MDPI AG 2013-04-01
• Series: International Journal of Molecular Sciences
• Subjects: allyl chloroformate; vinyl chloroformate; mechanisms; solvolysis; nucleophilicity; ionizing power; π electron cloud; Grunwald-Winstein equation; Linear Free Energy Relationships (LFERs)
• Online Access: http://www.mdpi.com/1422-0067/14/4/7286
• ISSN: 1422-0067

At 25.0 °C the specific rates of solvolysis for allyl and vinyl chloroformates have been determined in a wide mix of pure and aqueous organic mixtures. In all the solvents studied, vinyl chloroformate was found to react significantly faster than allyl chloroformate. Multiple correlation analyses of these rates are completed using the extended (two-term) Grunwald-Winstein equation with incorporation of literature values for solvent nucleophilicity (NT) and solvent ionizing power (YCl). Both substrates were found to solvolyze by similar dual bimolecular carbonyl-addition and unimolecular ionization channels, each heavily dependent upon the solvents nucleophilicity and ionizing ability.