Solvolysis of N,N-dimethylthiocarbamoyl chloride: effect of sulfur-for-oxygen substitution upon kinetics and product partitioning

• Published in: Journal of physical organic chemistry Vol. 13; no. 4; pp. 192 - 196
• Main Authors: Kevill, Dennis N., Rudolph, Todd M., D'Souza, Malcolm J.
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-04-2000
• Subjects: Grunwald-Winstein equation; N,N‐dimethylthiocarbamoyl chloride; N-dimethylthiocarbamoyl chloride; selectivity; solvolysis
• ISSN: 0894-3230; 1099-1395
• DOI: 10.1002/(SICI)1099-1395(200004)13:4<192::AID-POC228>3.0.CO;2-K

A study of the solvolyses of N,N‐dimethylcarbamoyl chloride (1) was extended to the solvolyses of N,N‐dimethylthiocarbamoyl chloride (2). The specific rates of solvolysis of 2 at 0.0 °C are two to three orders of magnitude greater than those for 1. Analysis of the data using the extended Grunwald–Winstein equation leads to sensitivities l and m and an l/m ratio which are lower for 2 than those previously reported for 1. Product selectivities in mixtures of water with ethanol or methanol indicate a greater preference for reaction with alcohol for 2. All observations can be rationalized in terms of the formation of a more stable carbocation from 2, leading to an earlier transition state, reduced nucleophilic solvation and the possibility of extensive progression to a free carbocation prior to product formation. Copyright © 2000 John Wiley & Sons, Ltd.