Rate and product studies with dimethyl phosphorochloridate and phosphorochloridothionate under solvolytic conditionsPresented, in part, at the Tenth Kyushu International Symposium on Physical Organic Chemistry, Fukuoka, October 2003. Abstracted in part from the MS thesis of J. S. C., Northern Illinois University, December 1998.
Kevill, Dennis N.; Carver, Jeffrey S.; Kevill Dennis N.; Department of Chemistry and Biochemistry, Northern Illinois University; Carver Jeffrey S.; Department of Chemistry and Biochemistry, Northern Illinois University
Журнал:
Organic & Biomolecular Chemistry
Дата:
2004
Аннотация:
The specific rates of solvolysis of dimethyl phosphorochloridate and of dimethyl phosphorochloridothionate are very well correlated using the extended Grunwaldâ Winstein equation, with incorporation of the NT solvent nucleophilicity scale and the YCl solvent ionizing power scale. The sensitivity parameters (l and m) are similar to each other and also similar to previously recorded values for solvolyses of arenesulfonyl chlorides, which were proposed to follow a concerted displacement mechanism. For solvolyses in aqueous ethanol or aqueous methanol the product selectivities (S) are close to unity. For solvolyses in aqueous 2,2,2-trifluoroethanol, the values are too small to accurately measure, showing a very large preference for product formation involving nucleophilic attack by the water component. It is concluded that the chloride and chloridothionate solvolyses, in common with the solvolyses of arenesulfonyl chlorides, follow a concerted displacement mechanism.
108.7Кб