An Efficient Preparation of β‐Dimethylaminovinyl Sulfone and Sulfoximide, and Investigation of Their Reactivity as Dipolarophiles.

Abstract

A simple reaction affording (E)-1-dimethylamino-2-phenylsulfonylethylene, and S- ((E)-2-(N',N'-dimethylamino)ethenyl)-S-phenyl-N-(p-tolylsulfonyl) sulfoximide in high yields is described. A reversal in regioselectivity was observed when the β-dimethylaminovinyl sulfone was employed as a dipolarophile in cycloadditions with nitrile oxides. The sulfone gives rise mainly to 4-substituted isoxazoles, after elimination of dimethyl amine. In comparison, phenyl vinyl sulfone cycloadds to give 5-substituted isoxazolines.Although not showing comparable dipolarophilic activity in reactions with nitrile oxides and nitrile imides, the β-dimethylaminovinyl sulfoximide was easily converted to S- ((E)-(3-ethoxycarbonyl)prop-2-enyl)-Sphenyl-N-(p-tolylsulfonyl) sulfoximide. This allylic sulfoximide cycloadds in good yield to both benzonitrile oxide and diphenylnitrile imide, but no stereoselectivity was observed in the process; and only modest regioselectivity was detected in the case of benzonitrile oxide.

Dehydrogenative Imination of Low-Valent Sulfur Compounds─Fast and Scalable Synthesis of Sulfilimines, Sulfinamidines, and Sulfinimidate Esters

“…Further examples of imination processes use iodine­(III) reagents to enable simultaneous N,O transfer resulting in NH sulfoximines, which can then be further functionalized in a wide variety of processes. ,, For the oxygenation, numerous literature precedents using strong oxidizers are available, such as H 2 O 2 /MeCN, m -CPBA, NaIO 4 /RuO 2 , , or KMnO 4 …”