Electrochemical N-Acylation of Sulfoximine with Hydroxamic Acid

Despite the widespread applications of sulfoximines, green and efficient access to functionalized sulfoximines remains a challenge. By employing an electrochemical strategy, we describe an approach for the construction of N-aroylsulfoximines, which features a broad substrate scope, mild reaction conditions, safety on a gram scale, and no need for an external oxidant and transition metal catalysts.

Electrochemical Oxidative Carbonylation of NH-Sulfoximines

The electrochemical synthesis of N-aroylsulfoximines features the use of tetra-n-butylammonium iodide (TBAI) as the medium and a broad substrate scope, thus affording a wide range of N-aroylated sulfoximines in moderate to good yields. The advantages of this electrochemical strategy are augmented by mild reaction conditions that are external oxidant-free, ligand-free, and easy to scale up to gram scale. Both the control experiments and the mechanistic studies revealed that the whole electrochemical process proceeded through a palladium (II/IV/II) catalytic cycle.

Direct formation and site-selective elaboration of methionine sulfoximine in polypeptides

Sulfoximines are emerging moieties for medicinal and biological chemistry, due in part to their efficacy in selective inhibition of amide-forming enzymes such as γ-glutamylcysteine synthetase. While small-molecule sulfoximines such as methionine sulfoximine (MSO) and its derivatives are well studied, structures with methionine sulfoximine residues within complex polypeptides have been generally inaccessible. This paper describes a straightforward means of late-stage one-step oxidation of methionine residues within polypeptides to afford NH-sulfoximines. We also present chemoselective subsequent elaboration, most notably by copper(ii)-mediated N-H cross-coupling at methionine sulfoximine residues with arylboronic acid reagents. This development serves as a strategy to incorporate diverse sulfoximine structures within natural polypeptides, and also identifies the methionine sulfoximine residue as a new site for bioorthogonal, chemoselective bioconjugation.

Synthesis and Transformations of NH-Sulfoximines

Recent years have seen a marked increase in the occurrence of sulfoximines in the chemical sciences, often presented as valuable motifs for medicinal chemistry. This has been prompted by both pioneering works taking sulfoximine containing compounds into clinical trials and the concurrent development of powerful synthetic methods. This review covers recent developments in the synthesis of sulfoximines concentrating on developments since 2015. This includes extensive developments in both S-N and S-C bond formations. Flow chemistry processes for sulfoximine synthesis are also covered. Finally, subsequent transformations of sulfoximines, particularly in N-functionalization are reviewed, including N-S, N-P, N-C bond forming processes and cyclization reactions.

Visible light-induced C-C bond cleavage in a multicomponent reaction cascade allowing acylations of sulfoximines with ketones

Visible light induces C-C-bond cleavage reactions of ketones, which can be utilized for N-acylations of sulfoximines. No (photo)catalyst is required, and the reactions occur at ambient temperature in air. The substrate scope is broad for both ketones and sulfoximines. For converting NH-sulfoximines, the presence of NBS is essential.

General Method for the Asymmetric Synthesis of N-H Sulfoximines via C-S Bond Formation

A versatile method for the synthesis of enantioenriched N-H sulfoximines is reported. The approach stems from the organomagnesium-mediated ring opening of novel cyclic sulfonimidate templates. The reactions proceed in high yield and with excellent stereofidelity with alkyl, aryl, and heteroaryl Grignard reagents. The chiral auxiliary is readily removed from the resultant sulfoximines via an unusual oxidative debenzylation protocol that utilizes molecular oxygen as the terminal oxidant. This provides a general strategy for the synthesis of highly enantioenriched N-H sulfoximines.

Synthesis ofN-sulfenyl-sulfoximines and -sulfenamides through a metal-free N–H/S–H dehydrocoupling reaction

A metal-free, iodine-catalyzed N–H/S–H dehydrocoupling reaction of sulfoximines and anilines with various thiols to construct sulfur–nitrogen bonds has been developed.

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

One-pot synthesis of NH-sulfoximines from sulfides was reported through fully described acetoxy- and methoxy-λ⁶-sulfanenitrile intermediates (¹H, ¹³C, ¹⁵N NMR and HRMS).

Synthesis of fully-substituted 1,2,3-triazoles via copper(i)-catalyzed three-component coupling of sulfoximines, alkynes and azides

A copper(i)-catalyzed three-component reaction of sulfoximines, alkynes and azides is described, affording a variety of 1,2,3-triazolyl-5-sulfoximines in moderate to good yields.

Sulfoximinocarbonylation of aryl halides using heterogeneous Pd/C catalyst

A heterogeneous Pd/C catalyzed three component protocol is developed for the sulfoximinocarbonylation of aryl halides.

Copper-catalyzed N-thioetherification of sulfoximines using disulfides

A novel copper-catalyzed N-thioetherification of sulfoximines under mild reaction conditions was developed using readily available disulfides as the sulfur source.