28859-91-8

Upstream product

• 142-84-7 di-n-propylamine 
• 98-09-9 benzenesulfonyl chloride 
• 17985-86-3 N,N-Di-n-propyl-diphenyl-phosphinsaeureamid 
• 80-18-2 Methyl benzenesulfonate 
• 369-57-3 benzenediazonium tetrafluoroborate 
• 102-69-2 tri-n-propylamine 
• 108-98-5 thiophenol 
• 57-66-9 4-[(dipropylamino)sulfonyl]benzoic acid 
• 201733-56-4 2-(5,5-dimethyl-1,3,2-dioxaborinan-2-yl)-5,5-dimethyl-1,3,2-dioxaborinane 

Downstream Products

• 98-10-2 benzenesulfonamide 
• 1450829-77-2 diethyl (2-(N,N-dipropylsulfamoyl)phenyl)phosphonate 

Relevant academic research and scientific papers

Highly-chemoselective step-down reduction of carboxylic acids to aromatic hydrocarbons: Via palladium catalysis

Aryl carboxylic acids are among the most abundant substrates in chemical synthesis and represent a perfect example of a traceless directing group that is central to many processes in the preparation of pharmaceuticals, natural products and polymers. Herein, we describe a highly selective method for the direct step-down reduction of carboxylic acids to arenes, proceeding via well-defined Pd(0)/(ii) catalytic cycle. The method shows a remarkably broad substrate scope, enabling to direct the classical acyl reduction towards selective decarbonylation by a redox-neutral mechanism. The utility of this reaction is highlighted in the direct defunctionalization of pharmaceuticals and natural products, and further emphasized in a range of traceless processes using removable carboxylic acids under mild, redox-neutral conditions orthogonal to protodecarboxylation. Extensive DFT computations were conducted to demonstrate preferred selectivity for the reversible oxidative addition and indicated that a versatile hydrogen atom transfer (HAT) pathway is operable.

Mechanism and Scope of Nickel-Catalyzed Decarbonylative Borylation of Carboxylic Acid Fluorides

This Article describes the development of a base-free, nickel-catalyzed decarbonylative coupling of carboxylic acid fluorides with diboron reagents to selectively afford aryl boronate ester products. Detailed studies were conducted to assess the relative rates of direct transmetalation between aryl boronate esters and diboron reagents and a bisphosphine nickel(aryl)(fluoride) intermediate. These investigations revealed that diboron reagents undergo transmetalation with this Ni(aryl)(fluoride) intermediate at rates significantly faster than their aryl boronate ester congeners. Furthermore, the reactivity of both boron reagents toward transmetalation is enhanced with increasing electrophilicity of the boron center. These mechanistic insights were leveraged to develop a catalytic decarbonylative borylation of acid fluorides that proved applicable to a variety of (hetero)aryl carboxylic acid fluorides as well as diverse diboron reagents. The acid fluorides can be generated in situ directly from carboxylic acids. Furthermore, the mechanistic studies directed the identification of various air-stable Ni pre-catalysts for this transformation.

Sulfonamide Synthesis through Electrochemical Oxidative Coupling of Amines and Thiols

Sulfonamides are key motifs in pharmaceuticals and agrochemicals, spurring the continuous development of novel and efficient synthetic methods to access these functional groups. Herein, we report an environmentally benign electrochemical method which enables the oxidative coupling between thiols and amines, two readily available and inexpensive commodity chemicals. The transformation is completely driven by electricity, does not require any sacrificial reagent or additional catalysts and can be carried out in only 5 min. Hydrogen is formed as a benign byproduct at the counter electrode. Owing to the mild reaction conditions, the reaction displays a broad substrate scope and functional group compatibility.

Sulfonamide Synthesis through Electrochemical Oxidative Coupling of Amines and Thiols

Sulfonamides are key motifs in pharmaceuticals and agrochemicals, spurring the continuous development of novel and efficient synthetic methods to access these functional groups. Herein, we report an environmentally benign electrochemical method which enables the oxidative coupling between thiols and amines, two readily available and inexpensive commodity chemicals. The transformation is completely driven by electricity, does not require any sacrificial reagent or additional catalysts and can be carried out in only 5 min. Hydrogen is formed as a benign byproduct at the counter electrode. Owing to the mild reaction conditions, the reaction displays a broad substrate scope and functional group compatibility.

Eosin Y-Sensitized Photocatalytic Reaction of Tertiary Aliphatic Amines with Arenesulfonyl Chlorides under Visible-Light Irradiation

A mild, practical, and environmentally friendly route to vinyl sulfones and sulfonamides has been developed based on the reaction of aliphatic amines with arenesulfonyl chlorides in the presence of eosin Y as a photocatalyst under visible light. The method permits the selective formation of vinyl sulfones or sulfonamides, depending on the oxidation environment and solvent. A wide range of products were obtained in moderate to good yields under the optimized conditions.

A Route to O-Aminosulfonates and Sulfonamides through Insertion of Sulfur Dioxide and Hydrogen Atom Transfer

A three-component reaction of aryldiazonium tetrafluoroborates, the 1,4-diazabicyclo[2.2.2]octane?bis(sulfur dioxide) adduct [DABCO?(SO2)2] and hydroxylamines under catalyst-free and additive-free conditions has been developed, providing aryl O-aminosulfonates in good yields. Sulfonamides could also be obtained via a one-pot process through the reaction of aryldiazonium tetrafluoroborates, DABCO?(SO2)2 and amines in the presence of N-hydroxybenzotriazole. A mechanism involving the insertion of sulfur dioxide and hydrogen atom transfer is proposed and supported by theoretical calculations. (Figure presented.).

Benzenesulfonyl chloride with primary and secondary amines in aqueous media - Unexpected high conversions to sulfonamides at high pH

We have determined pH-yield profiles under pseudo-first-order conditions of the reactions of benzenesulfonyl chloride with a set of primary and secondary water-soluble alkylamines, and have found with certain amines, such as dibutylamine, a profile taking the form of a sigmoid pH-yield curve with relatively high yields of the sulfonamide persisting with increasing basicity up to and including 1.0 mol/L sodium hydroxide. This behaviour is quantitatively accounted for by invoking, in addition to the usual second-order reaction of the sulfonyl chloride with the amine, two third-order terms (i) one first-order in sulfonyl chloride, amine and hydroxide anion, and (H) another first-order in sulfonyl chloride and second-order in the amine. The importance of the third-order terms correlates approximately with the total number of alkyl carbon atoms in the amine, and this in turn is regarded as related to the hydrophobic character of the amine. Experiments to test this picture included: (i) observation of a bell-shaped curve with bis(2-methoxyethyl)amine, (H) in the reaction of dibutylamine in THF-H2O (1:1), and also (iii) in the reaction of dibutylamine in 1.0 mol/L tetrabutylammonium bromide, and (iv) increase in the contributions of the third-order terms in 1.0 mol/L aqueous sodium chloride. Preparative reactions with dibutylamine, 1-octylamine, and hexamethylenimine in 1.0 mol/L aqueous sodium hydroxide with a 5% excess of benzenesulfonyl chloride gave, respectively, 94%, 98%, and 97% yields of the corresponding sulfonamides.