Abstract
The specific rates of solvolysis of ethyl fluoroformate have been measured at 24.2 °C in 21 pure and binary solvents. These give a satisfactory correlation over the full range of solvents when the extended Grunwald-Winstein equation is applied. The sensitivities to changes in the NT solvent nucleophilicity scale and the YCl solvent ionizing power scale, and the kF/kCl values are very similar to those for solvolyses of n-octyl fluoroformate, consistent with the addition step of an addition-elimination pathway being rate-determining. For methanolysis, a solvent deuterium isotope effect of 3.10 is compatible with the incorporation of general-base catalysis into the substitution process. For five representative solvents, studies were made at several temperatures and activation parameters determined. The results are also compared with those reported earlier for ethyl chloroformate and mechanistic conclusions are drawn.
Highlights
The extended Grunwald-Winstein Equation (1) can give information which is very helpful in assessing the mechanism of solvolysis reactions [1,2,3,4]
In Equation (1), k and ko are the specific rates of solvolysis of a substrate in a given solvent and in 80% ethanol, respectively; l is the sensitivity towards changes in NT, a scale of solvent nucleophilicity based on the specific rates of solvolysis of the
We reported that the specific rates of solvolysis of ethyl chloroformate (EtOCOCl) [19] can be very well correlated, after division into two solvent groups, using the extended Grunwald-Winstein equation
Summary
The extended Grunwald-Winstein Equation (1) can give information which is very helpful in assessing the mechanism of solvolysis reactions [1,2,3,4]. Both the NT and YCl scales are based on standard systems involving substitution reaction at an sp3-hybridized carbon [3,4], the scales have been used with considerable success in the correlation analyses of solvolysis reactions of substrates which have attack at the sp2-hybridized carbon of acyl halides [5,6,7] and chloroformate esters [8,9,10,11,12,13,14,15], and at the sulfur atom of sulfonyl halides [16]. A study of the mechanism of the reactions of fluoroformates under solvolytic conditions is of continuing interest
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
