Process for functionalizing a double bond
The invention concerns a method for functionalizing a double bond and, more particularly, a double bond bearing a metalloid atom. Said functionalization is produced by the action of perhalogenated sulphonyl chloride on the carbon bearing sulphur in the presence of a free radical initiator, preferably by homolytic cleavage. The invention is useful in organic synthesis.
1. A process for functionalizing a double bond corresponding to the following formula I:
wherein:
R 1 , R 2 and R 3 , are hydrogen atoms attached to said double bond via an sp 3 carbon, wherein:
Z is CH 2 —O—R 4 , where
R 4 is a hydrocarbyl or silyl group,
said process comprising the step reacting without polymerizing said double bond with a sulfonyl chloride compound perhalogenated on a sulfur-bearing carbon of the sulfonyl function, in the presence of a free-radical initiator, wherein the free-radical initiator is an initiator by homolytic cleavage.
2. The process according to claim 1 , wherein R 4 is an electron-withdrawing group.
3. The process according to claim 1 , wherein the perhalogenated sulfonyl chloride has the formula R f —SO 2 —Cl, wherein R f has the formula
EWG—(CX 2 ) p —, wherein:
X groups, which are similar or different, represent a chlorine atom, a fluorine atom or a group of formula C n F 2n+1 wherein n is an integer of not more than 5, with the condition that at least one of the X groups is fluorine,
p is integer of not more than 2,
EWG is an electron-withdrawing group, optionally comprising functions, said functions being inert under the reaction conditions, and
the total number of carbon atoms in R f is of between 1 and 15.
4. The process according to claim 3 , wherein:
X groups, which are similar or different, represent a chlorine atom, a fluorine atom or a group of formula C n F 2n+1 wherein n is an integer of not more than 2, with the condition that at least one of the X groups is fluorine, EWG is an electron-withdrawing group, comprising inert functions under the reaction conditions, said functions being a fluorine atom or a perfluoro residue of formula C n F 2n+1 , with n being an integer of not more than 8,
the total number of carbon in R f is of between 1 and 10.
5. The process according to claim 3 , wherein R f contains not more than 6 carbon atoms.
6. The process according to claim 5 , wherein R f contains not more than 3 carbon atoms.
7. The process according to claim 1 , wherein R 4 is an acyl group comprising not more than 15 carbon atoms.
8. The process according to claim 7 , wherein the acyl group comprises not more than 10 carbon atoms.