Iodine-Promoted Deoxygenative Iodization/Olefination/Sulfenylation of Ketones with Sulfonyl Hydrazides: Access to β-Iodoalkenyl Sulfides

Abstract

A highly regio- and stereoselective synthesis of β-haloalkenyl sulfides using commercially available ketones and sulfonyl hydrazides as starting materials has been developed. This protocol obviates the need for alkynes and traditional sulfenylating agents and therefore opens up a new door to construct β-iodoalkenyl sulfides in a highly simple manner. This study reveals that ketones could be used as vinyl iodide precursors in organic synthesis.

Metal‐Free Synthesis of β‐Bromoalkenyl Sulfides via Deoxygenative Bromination/Olefination/Sulfenylation of Ketones with Sulfonyl Hydrazides and Pyridinium Tribromide

“…Based on the above and our previous studies, [9,12,13] a proposed pathway is delineated (Scheme 3). Based on the above and our previous studies, [9,12,13] a proposed pathway is delineated (Scheme 3).…”

“…Sulfonyl hydrazides which are stable, commercially available and low-toxic could serve as ideal sulfenylating agents, [9] and they have been widely employed to react with ketones to deliver sulfonylhydrazones, which have been one of the most important synthons for the formation of various olefins since the seminal findings of Bamford-Stevens [10] and Shapiro. [12] This protocol obviates the need for alkynes and traditional sulfenylating agents. [12] This protocol obviates the need for alkynes and traditional sulfenylating agents.…”

Recent Advances in Iodine‐Promoted C−S/N−S Bonds Formation

“…In 2018, the Yang group reported an I 2 /KI‐promoted highly regio‐ and stereoselective synthesis of β‐haloalkenyl sulfides 143 from commercially available ketones 141 and sulfonyl hydrazides 142 , which opened an unprecedented pathway to β‐iodoalkenyl sulfides avoiding the use of alkynes and traditional thiolating reagents (Scheme 45). [116b] It is worth noting that the reaction demonstrated broad substrate scope with various aryl methyl ketones and aliphatic ketones. A series of control experiments with possible intermediates was performed to gain some insights into the reaction mechanism.…”

Sulfonyl Hydrazides in Organic Synthesis: A Review of Recent Studies

“…Then, an electrophilic addition from R 2 SI, 1,5‐H shift, elimination of HI were involved under I 2 ‐assisted conditions. Yang and co‐workers developed the sulfenylation of in situ generated gem ‐diiodide intermediates for the synthesis of β ‐iodoalkenyl sulfides (Eq. 71‐2) (Scheme ).…”