294209-40-8

Upstream product

• 109-99-9 tetrahydrofuran 
• 70-55-3 toluene-4-sulfonamide 
• 55962-05-5 4-methyl-N-[(E)-phenyl-λ³-iodanylidene]benzenesulfonamide 
• 55962-05-5 [N-(p-tolylsulfonyl)imino]phenyliodinane 
• 94-02-0 ethyl 3-oxo-3-phenylpropionate 
• 941-55-9 4-toluenesulfonyl azide 
• 98-59-9 p-toluenesulfonyl chloride 
• 1593-60-8 p-toluenesulfonylhydroxylamine 
• 21849-40-1 dibromamine-T 
• 41085-71-6 bromamine T 
• 127-65-1 chloroamine-T 

Downstream Products

• 78521-69-4 N-(3-hydroxybutyl)-4-methylbenzenesulfonamide 

Relevant academic research and scientific papers

Redox Self-Adaptation of a Nitrene Transfer Catalyst to the Substrate Needs

The development of iron catalysts for carbon–heteroatom bond formation, which has attracted strong interest in the context of green chemistry and nitrene transfer, has emerged as the most promising way to versatile amine synthetic processes. A diiron system was previously developed that proved efficient in catalytic sulfimidations and aziridinations thanks to an FeIIIFeIV active species. To deal with more demanding benzylic and aliphatic substrates, the catalyst was found to activate itself to a FeIIIFeIVL. active species able to catalyze aliphatic amination. Extensive DFT calculations show that this activation event drastically enhances the electron affinity of the active species to match the substrates requirements. Overall this process consists in a redox self-adaptation of the catalyst to the substrate needs.

Nitrene Photochemistry of Manganese N-Haloamides**

Manganese complexes supported by macrocyclic tetrapyrrole ligands represent an important platform for nitrene transfer catalysis and have been applied to both C?H amination and olefin aziridination catalysis. The reactivity of the transient high-valent Mn nitrenoids that mediate these processes renders characterization of these species challenging. Here we report the synthesis and nitrene transfer photochemistry of a family of MnIII N-haloamide complexes. The S=2 N-haloamide complexes are characterized by 1H NMR, UV-vis, IR, high-frequency and -field EPR (HFEPR) spectroscopies, and single-crystal X-ray diffraction. Photolysis of these complexes results in the formal transfer of a nitrene equivalent to both C?H bonds, such as the α-C?H bonds of tetrahydrofuran, and olefinic substrates, such as styrene, to afford aminated and aziridinated products, respectively. Low-temperature spectroscopy and analysis of kinetic isotope effects for C?H amination indicate halogen-dependent photoreactivity: Photolysis of N-chloroamides proceeds via initial cleavage of the Mn?N bond to generate MnII and amidyl radical intermediates; in contrast, photolysis of N-iodoamides proceeds via N?I cleavage to generate a MnIV nitrenoid (i.e., {MnNR}7 species). These results establish N-haloamide ligands as viable precursors in the photosynthesis of metal nitrenes and highlight the power of ligand design to provide access to reactive intermediates in group-transfer catalysis.

Organophotoredox-Catalyzed Decarboxylative N-Alkylation of Sulfonamides

We developed an organophotoredox-catalyzed reaction for N-alkylation of sulfonamides with aliphatic carboxylic acid-derived redox active esters as alkylating reagents. Under mild and transition metal-free conditions, a series of functionalized N-alkylated sulfonamides were prepared. This protocol also enabled the functionalization of pharmaceutical drugs bearing a sulfonamide or carboxylic acid moiety. This radical-mediated process allowed the assembly of three components including sulfonamides, redox active esters, and alkenes to yield complex sulfonamides in a one-pot manner.

Metal-free C-H Activation over Graphene Oxide toward Direct Syntheses of Structurally Different Amines and Amides in Water

Unprecedented metal-free synthesis of a variety of amines and amides is reported via amination of C(sp3)-H and C(sp2)-H bonds. The strategy involves graphene-oxide/I2-catalyzed nitrene insertion using PhINTs as a nitrene (NT) source in water at room temperature. A wide range of structurally different substrates, viz., cyclohexane, cyclic ethers, arenes, alkyl aromatic systems, and aldehydes/ketones, having an α-phenyl ring have been employed successfully to afford the corresponding nitrene insertion product in good yield, albeit low in few cases. The envisaged method has superiority over others in terms of its operational simplicity, metal-free catalysis, use of water as a solvent, ambient reaction conditions, and reusability of the catalyst.

Observation of a Photogenerated Rh2 Nitrenoid Intermediate in C-H Amination

Rh2-catalyzed C-H amination is a powerful method for nitrogenating organic molecules. While Rh2 nitrenoids are often invoked as reactive intermediates in these reactions, the exquisite reactivity and fleeting lifetime of these species has precluded their observation. Here, we report the photogeneration of a transient Rh2 nitrenoid that participates in C-H amination. The developed approach to Rh2 nitrenoids, based on photochemical cleavage of N-Cl bonds in N-chloroamido ligands, has enabled characterization of a reactive Rh2 nitrenoid by mass spectrometry and transient absorption spectroscopy. We anticipate that photogeneration of metal nitrenoids will contribute to the development of C-H amination catalysis by providing tools to directly study the structures of these critical intermediates.

A Metal–Organic Framework with Exceptional Activity for C?H Bond Amination

The development of catalysts capable of fast, robust C?H bond amination under mild conditions is an unrealized goal despite substantial progress in the field of C?H activation in recent years. A Mn-based metal–organic framework (CPF-5) is described that promotes the direct amination of C?H bonds with exceptional activity. CPF-5 is capable of functionalizing C?H bonds in an intermolecular fashion with unrivaled catalytic stability producing >105 turnovers.

Nondirected, cu-catalyzed sp3 C-H aminations with hydroxylamine-based amination reagents: Catalytic and mechanistic studies

This work demonstrates the use of hydroxylamine-based amination reagents RSO2NH-OAc for the nondirected, Cu-catalyzed amination of benzylic C-H bonds. The amination reagents can be prepared on a gram scale, are benchtop stable, and provide benzylic C-H amination products with up to 86% yield. Mechanistic studies of the established reactivity with toluene as substrate reveal a ligand-promoted, Cu-catalyzed mechanism proceeding through Ph-CH2(NTsOAc) as a major intermediate. Stoichiometric reactivity of Ph-CH2(NTsOAc) to produce Ph-CH2-NHTs suggests a two-cycle, radical pathway for C-H amination, in which the decomposition of the employed diimine ligands plays an important role.

Metal-Free Amidation of Ethers with N, N -Dibromosulfonamides

A new metal-free amidation of ethers with N,N-dibromosulfonamides has been developed. A series of hemiaminal ethers or imines were prepared with moderate to good yields.

Iminoiodane- and Br?nsted base-mediated cross dehydrogenative coupling of cyclic ethers with 1,3-dicarbonyl compounds

A one-pot, two-step approach to prepare 2-tetrahydrofuran and -pyran substituted 1,3-dicarbonyl compounds by PhI=NTs-mediated amination/Br?nsted base-catalyzed cross dehydrogenative coupling (CDC) reaction of the cyclic ether and 1,3-dicarbonyl derivative under mild conditions is reported. The reaction is compatible with a variety of cyclic ethers and 1,3-dicarbonyl compounds, affording the corresponding coupled products in moderate to good yields of up to 80% over two steps.

Metal-free amidation of ether sp3 C-H bonds with sulfonamides using PhI(OAc)2

A selective protocol for the metal-free α-C-H amidation of ethers using sulfonamides and hypervalent iodine oxidants has been developed. The absence of precious metals and the conditions employed make the method environmentally attractive. A number of cyclic and acyclic, linear and branched ethers have been successfully amidated, and a broad sulfonamide scope has been demonstrated. Two unusual reactions, namely the amidation of an unactivated tert-butyl group and a tandem C-C coupling reaction, are also described. This journal is