Sulfonyl Hydrazides Research Articles

Copper-catalyzed S-methylation of sulfonyl hydrazides with TBHP for the synthesis of methyl sulfones in water

A copper-catalyzed S-methylation of sulfonyl hydrazides with TBHP for the synthesis of methyl sulfones in water.

A method for accessing sulfanylfurans from homopropargylic alcohols and sulfonyl hydrazides.

A sulfenylation/cyclization reaction has been developed for the synthesis of sulfanylfurans in the presence of iodine. These processes provide facile strategies to construct C-S/O bonds, and expand the methods of synthesizing sulfanylfurans. In this transformation, various groups on homopropargylic alcohols and sulfonyl hydrazides react smoothly and the desired sulfanylfurans are obtained in moderate to good yields.

Rhodium-catalyzed addition of sulfonyl hydrazides to allenes: regioselective synthesis of branched allylic sulfones.

A rhodium-catalyzed regioselective addition of sulfonyl hydrazides to allenes is reported. With Rh(i)/DPEphos/benzoic acid as the catalyst system, branched allylic sulfones can be obtained, in good to excellent yields and regioselectivities.

Regioselective thiolation of electron rich arenes and heterocycles in recyclable catalytic media

A convenient and novel approach has been developed for the synthesis of unsymmetrical diaryl sulfides by the reaction of sulfonyl hydrazides with phenols, aromatic amines and heterocycles using a [Bmim][Br] ionic liquid through C–S bonds formation.

ChemInform Abstract: Iodine‐Catalyzed Regioselective Thiolation of Flavonoids Using Sulfonyl Hydrazides as Sulfenylation Reagents.

AbstractRegioselective aryl and alkyl thiolation reactions of flavonoid derivatives are described which proceed in position C‐8 for C‐5 hydroxylated flavone, flavonol, dihydroflavone, and isoflavones derivatives, or in position 7 in case of C‐4 hydroxylated aurone derivatives.

By‐Product‐Catalyzed Redox‐Neutral Sulfenylation/Deiodination/Aromatization of Cyclic Alkenyl Iodides with Sulfonyl Hydrazides

AbstractA by‐product‐catalyzed redox‐neutral process has been established through tandem sulfenylation/deiodination/aromatization of cyclic alkenyl iodides with sulfonyl hydrazides. In the absence of external catalysts and additives a range of 4‐iodo‐1,2‐dihydronaphthalenes reacted with sulfonyl hydrazides to give structurally diverse 2‐naphthyl thioethers in good yields. Mechanistic studies showed that at an early stage sulfonyl hydrazides decomposed completely to thiosulfonates and disulfides and at a late stage the resulting thiosulfonates underwent tandem sulfenylation/deiodination/aromatization with 4‐iodo‐1,2‐dihydronaphthalenes involving a [1,5]‐sigmatropic hydrogen shift. Importantly, iodine was generated as a by‐product from 4‐iodo‐1,2‐dihydronaphthalenes upon heating and served as a catalyst for the decomposition of sulfonyl hydrazides and subsequent formation of 2‐naphthyl thioethers.magnified image

ChemInform Abstract: In situ Generated Hypoiodite Activator for the C2 Sulfonylation of Heteroaromatic N‐Oxides.

AbstractA novel NaI/tert‐butyl hydroperoxide‐mediated direct α‐sulfonylation of heteroaromatic N‐oxides with sulfonyl hydrazides is described.

Bu4NI-Catalyzed Cross-Coupling between Sulfonyl Hydrazides and Diazo Compounds To Construct β-Carbonyl Sulfones Using Molecular Oxygen

A new cross-coupling reaction between sulfonyl hydrazides and diazo compounds has been established, leading to a variety of β-carbonyl sulfones in good yields. This methodology was distinguished by simple manipulation, easily available starting materials, and wide substrate scope. A plausible mechanism involving a radical process was proposed based upon the experimental observations and literature.

ChemInform Abstract: Catalyst‐Free Thiolation of Indoles with Sulfonyl Hydrazides for the Synthesis of 3‐Sulfenylindoles in Water.

A catalyst-free thiolation of indoles with sulfonyl hydrazides was efficiently developed in water under mild conditions without any ligand or additive. The reaction provided a variety of 3-sulfenylindoles with good to excellent yields and the only by-products were nitrogen and water.

ChemInform Abstract: Tandem Approach for the Synthesis of 3‐Sulfenylimidazo[1,5‐a]pyridines from Dithioesters.

AbstractA library of sulfenylimidazopyridines synthesized from dithioesters, 2‐methylaminopyridines, and sulfonyl hydrazides using iodine as the reagent under metal‐free conditions.

In Situ Generated HypoIodite Activator for the C2 Sulfonylation of Heteroaromatic N-oxides.

A mild approach for direct C2 sulfonylation of heteroaromatic N-oxides with sulfonyl hydrazides affording 2-sulfonyl quinolines/pyridines has been developed. A variety of heteroaromatic N-oxides and sulfonyl hydrazides participate effectively in this transformation which uses hypoiodites (generated in situ from NaI and TBHP) as a means of substrate activators. In this reaction, the N-oxide plays a dual role, acting as a traceless directing group as well as a source of oxygen atom.

ChemInform Abstract: Copper‐Catalyzed Aerobic Oxidative Reaction of Sulfonyl Hydrazides with Alcohols: An Easy Access to Sulfinates.

A Cu-catalyzed aerobic oxidative reaction between sulfonyl hydrazides and alcohols has been developed. In this reaction, sulfonyl hydrazides act as the sulfinic acid precursors to react with alcohols, resulting in sulfinic esters with up to 72 % yield. This catalytic system tolerates a wide range of sulfonyl hydrazide substrates, and represents a new strategy for the transformation of readily available sulfonyl hydrazides.

ChemInform Abstract: Microwave‐Assisted Synthesis of 3‐Sulfenylindoles by Sulfonyl Hydrazides Using Organic Ionic Base‐Broensted Acid.

AbstractSulfenylindoles are prepared via a DBU‐based ionic liquid‐promoted sulfenylation of indoles using sulfonyl hydrazides as thiol surrogate.

ChemInform Abstract: Oxysulfonylation of Alkenes with Sulfonyl Hydrazides under Transition‐Metal‐Free Conditions

Abstractaffording structurally diverse β‐keto sulfones

ChemInform Abstract: Metal‐Free Synthesis of Sulfonamides via Iodine‐Catalyzed Oxidative Coupling of Sulfonyl Hydrazides and Amines.

Abstract A novel, rapid, and environmentally-friendly protocol for the synthesis of sulfonamides using iodine as catalyst under solvent-free conditions is described. This method involves the oxidative coupling of sulfonyl hydrazides and amines in the presence of catalytic amount of iodine using TBHP as oxidant. This protocol does not require purification techniques such as column chromatography and recrystalization.

ChemInform Abstract: Iron‐Catalyzed Oxidative Sulfonylation of Enol Acetates: An Environmentally Benign Approach to β‐Keto Sulfones.

AbstractThis is the first example of an iron‐catalyzed sulfonylation of aryl enol acetates with sulfonyl hydrazides to yield β‐keto sulfones.

Microwave-assisted synthesis of new sulfonyl hydrazones, screening of biological activities and investigation of structure–activity relationship

Sulfonyl hydrazone scaffold and the piperidine rings have important role in medicinal chemistry. This study shows the synthesis of two novel series of sulfonyl hydrazone having piperidine derivatives by condensing benzene sulfonyl hydrazides with ethyl 4-oxopiperidine-1-carboxylate and 2,6-diphenylpiperidin-4-one. Physical and chemical properties of compounds have been characterized and reported by utilizing their melting point, elemental analysis, IR, 1H-NMR, 13C NMR, 2D NMR and mass spectra results. Synthesized compounds were evaluated for antioxidant capacity and anticholinesterase activity. The antioxidant capacity of the compounds were screened through four complementary test, i.e., β-carotene–linoleic acid for lipid peroxidation, DPPH free radical (DPPH·), ABTS cation radical (ABTS+·) and CUPRAC assays. Assay results showed that N′-(2,6-diphenylpiperidin-4-ylidene)-4-bromobenzenesulfonohydrazide (11) has the highest lipid peroxidation inhibitory activity. Within the assay series, N′-(2,6-diphenylpiperidin-4-ylidene)-4-bromobenzenesulfonohydrazide (11) exhibited better activity than standard BHT in DPPH· scavenging, while N′-(2,6-diphenylpiperidin-4-ylidene)benzenesulfonohydrazide (10) showed the best ABTS+· scavenging assay. The CUPRAC assay revealed that ethyl 4-(2-(4-methoxyphenylsulfonyl)hydrazono)piperidine-1-carboxylate (5) indicated the best activity with A 0.50 value among the tested compounds than the antioxidant standard α-tocopherol. According to AChE assay, N′-(2,6-diphenylpiperidin-4-ylidene)-4-chlorobenzenesulfonohydrazide (12) had the best activity, while in BChE assay the highest activity was found for compound N′-(2,6-diphenylpiperidin-4-ylidene)-4-methylbenzenesulfonohydrazide (16). Electronic and structural characteristics and density functional studies of the all newly synthesized compounds have been reported for better understanding in molecular-level. NMR, molecular electrostatic potential (MEP), ΔE HOMO–LUMO band gap and the dipole moments of the molecules have been also analyzed and reported.

ChemInform Abstract: Iodine‐Mediated Synthesis of Aromatic Thioethers with Aromatic Amines and Sulfonyl Hydrazides in High Regioselectivity via C(sp2)—H Bond Functionalization.

AbstractA convenient synthesis of bis(aryl) thioethers having a para‐amino substituent is rendered possible by a highly regioselective oxidative C—H coupling of N,N‐disubstituted anilines with arylsulfonyl hydrazides.

ChemInform Abstract: Iodine‐Promoted Radical Cyclization in Water: A Selective Reaction of 1,6‐Enynes with Sulfonyl Hydrazides.

AbstractThis new cyclization process proceeds in water under metal‐free conditions to afford a series of sulfonylated products in good yields with C—S and C—I bond formation in one step.

ChemInform Abstract: Iodine‐Catalyzed Expeditious Synthesis of Sulfonamides from Sulfonyl Hydrazides and Amines.

AbstractA new protocol for the synthesis of sulfonamides via an iodine‐catalyzed sulfonylation of amines with sulfonyl hydrazides is developed.