The Reactions of Alkenes with Phenyl-N-triflylimino-λ3-iodane: Solvent and Oxidant Impact

Abstract

The reactions of alkenes with phenyl-N-triflylimino-λ3-iodane PhI=NTf (1) have been studied in different conditions. In methylene chloride, in the presence of N-halosuccinimides, the products of mono and bis-triflamidation were obtained. In MeCN, the product of bromotriflamidation (with NBS) with solvent interception or of bis-triflamidation (with NIS) is formed. The reaction with trans-stilbene in acetonitrile with NBS gave rise to cyclization to 2-methyl-4,5-diphenyl-1-triflyl-4,5-dihydro-1H-imidazole. In contrast, with NIS as an oxidant, both in CH2Cl2 and MeCN, the major product was 2,3-diphenyl-1-triflylaziridine formed in good yield. With NBS, aziridine is also formed but as a minor product, the major one being a mixture of diastereomers of the product of bromotriflamidation. The reaction of compound 1 with vinylcyclohexane in methylene chloride affords the mixtures of regioisomers of the products of halotriflamidation, whereas in acetonitrile, the products of solvent interception and cyclization to the imidazoline are formed. A mechanism explaining the formation of all isolated products is proposed.

Halosulfonamidation of camphene: chemo and stereoselectivity, rearrangement, solvent interception, heterocyclization

“…With this in mind, and given our continued interest in oxidative sulfonamidation, 22–27 in this work we investigated the reactions of oxidative addition of sulfonamides RSO 2 NH 2 1a–k (R = CF 3 ) ( a ), 4-MeOC 6 H 4 ( b ), 4-MeC 6 H 4 ( c ), Ph ( d ), 4-ClC 6 H 4 ( e ), 4-BrC 6 H 4 ( f ), 4-NO 2 C 6 H 4 ( g ), 2-CF 3 C 6 H 4 ( h ), 4-CF 3 C 6 H 4 ( i ), NH 2 ( j ), Me ( k ) to camphene 2 in the presence of NBS, NIS, and t BuOCl/NaI in the solvents MeCN and CH 2 Cl 2 .…”