2-Hexenoic acid → 3-Sulfohexanoic acid
Reaction equation
[C:1]([OH:8])(=[O:7])[CH:2]=[CH:3][CH2:4][CH2:5][CH3:6].[OH-].[Na+].[S:11](=[O:14])([OH:13])[O-:12].[Na+].S(=O)(O)[O-]>>[S:11]([CH:3]([CH2:4][CH2:5][CH3:6])[CH2:2][C:1]([OH:8])=[O:7])([OH:14])(=[O:13])=[O:12]Participants
5
Procedure
114 g. of 2-hexenoic acid is neutralized with aqueous sodium hydroxide and reacted with 204 g. of a 50% wt. aqueous solution of sodium bisulfite at 25° C. Complete addition of bisulfite to the double bond requires several hours. The product is concentrated to approximately 50% wt. solids and then treated with a strong acid ion exchange resin to obtain an aqueous solution of 3-sulfohexanoic acid. This is dried by vacuum stripping and converted into 3-propyl-1,2-oxathiolane-5-one-2,2-dioixde with refluxing thionyl chloride at 80° C. for 3 hours. Equivalent weight is 93.