Electrochemical multi-component reaction of potassium metabisulfite with alkenes and alcohols enabling synthesis of sulfonate esters

Abstract

An electrochemical sulfur dioxide insertion reaction of alkenes and alcohols with potassium metabisulfite as the sulfur dioxide surrogate has been developed, which provides a green and efficient method for the preparation of sulfonate esters.

Multicomponent Reactions Based on SO2 Surrogates: Recent Advances

“…In addition to the photo catalysis and transition‐metal catalysis, electrochemical strategies are also emerging in the field of SO 2 insertion. In 2022, Han group described an electrochemical three‐component reaction between K 2 S 2 O 5 , styrene derivatives and alkyl alcohols, [60] delivering β ‐alkoxyl sulfonate esters 78 with high atom and step economy. Methanol, ethanol, n ‐propanol and isopropanol were all compatible with this protocol and produced the desired products in yields ranging from 48 % to 77 % (Figure 26).…”

Recent Developments in Selenylation and Thiolation of Alkenes via Three‐component Reactions

“…Mei and co‐workers [77] employed inorganic reagent K 2 S 2 O 8 as sulfonyl source to achieve the construction of sulfonate esters 58.1 . Initially, K 2 S 2 O 8 underwent anodic oxidation to form sulfur dioxide radical cation 58.2 .…”

“…Mei and co-workers [77] in alcohol ( n BuOH, 37%), or using a bulky alkyl group ( t BuOH, trace) would decrease the yield. K 2 S 2 O 8 is solid stable, cheap and easy to handle.…”

Electrochemically Enabled Sulfoximido-Oxygenation of Alkenes with NH-Sulfoximines and Alcohols

“…Many groups have developed a series of seminal electrochemical difunctionalization reactions of alkenes for the formation of C–C and C–X (O, N, S, etc.) bonds. − ,− For these difunctionalization reactions of alkenes, radical species are generally generated first under electrochemical conditions to attack the double bond of alkenes to afford a new carbon radical, which reacts with another radical, or be further oxidized and sequentially trapped by an external nucleophile to give the desired difunctionalized products with high regioselectivity . An alternative strategy is to employ alkene-derived radical cation intermediates to achieve difunctionalization of alkenes with two nucleophiles .…”