Patent ID: 8822706

Claim:
A method for preparing 2-hydroxybutyrolactone (2HBL) from a compound, or from its salt or its oligomers, said compound fitting formula (I) CH3-S—CH2CH2CR1R2R3 wherein R1 represents H R2 represents OH; or R1 and R2 together represent ═O; R3 represents COOH or COO—CH(CH 3 ) 2 , method according to which a sulfonium of said compound is obtained, said sulfonium fitting the formula (II) [CH3][CH2CH2CR1R2CR3][CR6R7R8]S+X− wherein R1, R2 and R3 have the above definition, and R6 and R7 are selected independently of each other from H and linear, cyclic, alicyclic or branched alkyl groups having from 1 to 10 carbon atoms; R8 is selected from H, CH3, phenyl, COOH, and linear, cyclic, alicyclic or branched alkyl groups having from 1 to 10 carbon atoms, and the thereby obtained sulfonium is hydrolyzed, and 2,4-dihydroxybutyric acid or its salt is cyclized into 2 hydroxybutyrolactone.