220166-62-1

Upstream product

• 95-54-5 1,2-diamino-benzene 
• 98-74-8 4-Nitrobenzenesulfonyl chloride 

Downstream Products

• 220165-50-4 1,4-ditosyl-2-vinyl-1,2,3,4-tetrahydroquinoxaline 
• 220167-11-3 1,2,3,4-tetrahydro-2-vinylquinoxaline 
• 49633-27-4 2-hydroxymethyl-1,4-bis-(toluene-4-sulfonyl)-1,2,3,4-tetrahydro-quinoxaline 

Relevant academic research and scientific papers

A Versatile Synthesis of Vinyl-Substituted Heterocycles via Regio- And Enantioselective Pd-Catalyzed Tandem Allylic Substitution

We herein report a versatile, regio- and enantioselective palladium-catalyzed tandem allylic substitution powered by a chiral bisphosphorus ligand WingPhos with the palladium loading as low as 0.1 mol %, forming a series of chiral vinyl-substituted heterocycles, including tetrahydroquinoxalines, piperazines, dihydro-2H-benzo[b][1,4]-oxazines, and morpholines, in exellent ee's and yields. The protocol features readily available starting materials, mild reaction conditions, and a broad substrate scope. Mechanistic investigation supports a tandem allylic substitution process.

Bis(sulfonamide) transmembrane carriers allow pH-gated inversion of ion selectivity

Bis(sulfonamide) based synthetic carriers are reported for inversion of ion selectivity upon deviation of pH within a narrow window. A liposomal membrane potential is also generated when potassium ions are passively transported by these carriers.

Urea-, squaramide-, and sulfonamide-based anion receptors: A thermodynamic study

In this work, we compare the anion-binding capabilities of receptors 1-5, characterized by similar structures, but possessing different hydrogen-bond-donor moieties (urea, squaramide, and sulfonamide). The presence of chromophoric substituents on the receptor's skeleton allowed the determination of association constants by performing UV/Vis titrations with the investigated anions on solutions of the receptors in pure acetonitrile. Additional quantitative studies of the anion-binding properties of receptors 1-5 were performed by isothermal titration calorimetry (ITC). The experimental results indicated that 1 and 2 formed 1:1 hydrogen-bonded complexes with most of the anions investigated. In the case of receptors 3-5, the formation of the 1:1 adduct was observed only with anions of low basicity (i.e., chloride, bromide, iodide, and hydrogen sulfate). With more basic anions (i.e., acetate and dihydrogen phosphate), both spectrophotometric and ITC titrations accounted for the deprotonation of the sulfonamide group, involving the formation of the conjugated base of the receptor. Copyright

Palladium(0)-catalyzed asymmetric synthesis of 1,2,3,4-tetrahydro-2- vinylquinoxalines

Reaction of (Z)-1,2-bis(methoxycarbonyloxy)but-2-ene (2) with various N,N-bis(arylsulfonyl)-o-phenylenediamines 1 was catalyzed by a palladium complex associated with chiral ligands to give optically active 1,4- bis(arylsulfonyl)-1,2,3,4-tetrahydro-2-vinylquinoxalines 3 with up to 62% ee. The use of (S)-MeOBIPHEP as the chiral ligand and N,N-bis(p-tolylsulfonyl)-o- phenylenediamine (1i) as the nucleophile led to the highest ee at 25 °C, regardless of the solvent used. The enantioselectivity of the cyclization is strongly affected by the nature of the substituents at the nitrogen atom.