50984-03-7Relevant academic research and scientific papers
The rearrangement of benzylic trichloromethane-sulfenates to sulfoxides and chlorides
Braverman,Sredni
, p. 2379 - 2384 (2007/10/11)
While benzyl trichloromethanesulfenate undergoes no rearrangement to sulfoxide even at high temperatures, the corresponding anisyl ester rearranges to p-anisyl trichloromethyl sulfoxide in hexane under mild conditions. Substitution of hexane by chloroform under similar conditions, lead to the formation of p-anisyl chloride and dichlorosulfine as main reaction products. This process is enhanced by the use of more polar solvents and higher temperatures. The conversion of trichloromethanesulfenate to chloride has also been observed with the benzyl and benzhydryl esters on heating in various solvents, though at very differing rates. Both rearrangements are suggested to take place by an ionization mechanism. Depending on the reaction conditions and nature of the substrate, the sulfenate anion can either recombine with the cation to give sulfoxide, or further dissociate to dichlorosulfine and chloride ion, which gives the benzyl chloride. The observation of an SN1 type mechanism for rearrangement of sulfenates appears to be unique.
Sulphur-oxygen versus carbon-oxygen bond fission in the solvolysis of benzyl sulphenates
Braverman,Reisman
, p. 3891 - 3896 (2007/10/05)
In contrast to p-anisyl trichloromethanesulphenate 1, which readily undergoes ethanolysis at room temperature with carbon-oxygen bond fission, the ethanolysis of the corresponding 2-nitrobenzenesulphenate 2 proceeds at a similar rate only at 100°, and involves sulphur-oxygen bond cleavage. While the solvolysis of 1 showed first-order kinetics, the solvolysis of 2 was second-order (first-order with respect to ester and to added base). The solvolysis rate of 2 decreases on going from 100% to 80% ethanol and by using pyridine instead of acetate as base, consistent with an SN2 type mechanism involving nucleophilic displacement at sulphur by the base or lyate ion. The rate of solvolysis of 1 is greatly enhanced in polar solvents and correlates satisfactorily with the ionization of p-methoxyneophyl tosylate. An ionization mechanism to some ion pair species is suggested for the solvolysis of 1.
