Mechanistic investigation of the NH-sulfoximination of sulfide. Evidence for λ⁶-sulfanenitrile intermediates

Abstract

We report a new procedure for the preparation of NH-sulfoximines from sulfides using PIDA as an oxidant and ammonium carbamate as the ammonia source. Excellent yields were obtained with a wide range of sulfides. The formation of acetoxy- and methoxy-λ-sulfanenitrile as intermediates was proposed, both of which were converted to the NH-sulfoximine by the action of the solvent. The structure of these intermediates was confirmed by H,C and N NMR and HRMS analysis.

A New, Practical One‐Pot Synthesis of Unprotected Sulfonimidamides by Transfer of Electrophilic NH to Sulfinamides

“…[20] Furthermore, this facile and new NHtransfer methodw as applicable to aw ide substrate scope and tolerated al arge number of heterocyclesa nd otherf unctionalities. [21] Attracted by the use of commercial reagents and the robust results of this new one-pot method,w ew erei ntrigued as to whether these safe reactionc onditions could also be usefulf or the facile synthesis of sulfonimidamides 2 by NH transfer to sulfinamides 6.…”

One‐Pot Synthesis of Aryl‐ and Alkyl S‐Perfluoroalkylated NH‐Sulfoximines from Sulfides

“…We postulate that a H‐bonded adduct between the TFE and PIDA led to the formation of the [PhI(OAc)] + cation A . In the presence of ammonia, nitrene B should be formed, as described by Luisi and Bull and by Reboul, in the non‐fluorinated series . The TFE would also be involved in the formation of the activated nitrene [PhI + N] C through H‐bonding.…”

“…With TFE, a moderate yield of 42 % of sulfoximine 8 a was obtained, whereas with methanol, the sulfoximines 8 a and 8 b were isolated in excellent yields of 80 % and 89 % respectively. These last conditions, which were already described for the non‐fluorinated series, were only efficient for these two S ‐difluoromethyl and S ‐monofluoromethyl substrates with an emphasis for the latter . In other cases, TFE is essential.…”

“…The group of Reboul recently developed an efficient synthesis of non‐fluorinated NH ‐sulfoximines from sulfides using phenyliodine diacetate (PIDA) and ammonium carbamate (AC). with methanol as the solvent . However, when the reaction was conducted in this solvent using trifluoromethyl phenyl sulfide 1 a , only traces of the desired NH ‐sulfoximine 2 a were detected by 19 F NMR analysis of the crude product and sulfide 1 a was recovered (Table , entry 1).…”

Bicyclo[1.1.1]pentyl Sulfoximines: Synthesis and Functionalizations

“…Unprotected sulfoximines can be synthesized from sulfoxides involving a transition‐metal catalyst or metal‐free using ammonium carbamate . The direct synthesis of sulfoximines from sulfides using the same ammonium source with diacetoxyiodobenzene as oxidant was simultaneously investigated by Bull and Luisi and Reboul . Sulfoximine syntheses from sulfilimines and different N ‐substituted sulfoximines are summarized in a recent review (Scheme ).…”