1023247-22-4Relevant academic research and scientific papers
Copper-catalyzed N-alkylation of sulfonamides with benzylic alcohols: Catalysis and mechanistic studies
Cui, Xinjiang,Shi, Feng,Tse, Man Kin,Goerdes, Dirk,Thurow, Kerstin,Beller, Matthias,Deng, Youquan
, p. 2949 - 2958 (2009)
The N-alkylation of sulfonamides with alcohols is efficiently performed in the presence of easily available copper catalysts via hydrogen borrowing methodology. Applying a copper acetate/potassium carbonate system the reaction of sulfonamides and alcohols gave the corresponding secondary amines in excellent yield. In situ HR-MS analysis indicated that bissulfonylated amines are formed under air atmosphere, which act as self-stabilizing Iigands for the catalytic system. UV-visible measurements suggest the interaction between the copper centre and the bissulfonylated amine. Reactions of benzyl alcohol-d 7 with p-toluenesulfonamide, Nbenzyl-p-toluenesulfonamide or N-benzylidenetoluenesulfonamide revealed that the reaction proceeds via a transfer hydrogenation mechanism and the whole process is micro-reversible. Competitive reactions of benzyl alcohol and benzyl alconol-d7 with ptoluenesulfonamide revealed a kinetic isotope effect (kH/kD) of 3.287 (0.192) for the dehydrogenation of benzyl alcohol and 0.611 (0.033) for the hydrogenation of the N-benzylidene-p-toluenesulfonamide intermediate, which suggests that dehydrogenation of the alcohol is the rate-determining step.
Organic ligand-free alkylation of amines, carboxamides, sulfonamides, and ketones by using alcohols catalyzed by heterogeneous Ag/Mo oxides
Cui, Xinjiang,Zhang, Yan,Shi, Feng,Deng, Youquan
supporting information; experimental part, p. 1021 - 1028 (2011/03/20)
Complicated and expensive organic ligands are normally essential in fine chemical synthesis at preparative or industrial levels. The synthesis of fine chemicals by using heterogeneous catalyst systems without additive organic ligand is highly desirable but severely limited due to their poor generality and rigorous reaction conditions. Here, we show the results of carbon-nitrogen or carbon-carbon bond formation catalyzed by an Ag/Mo hybrid material with specific Ag6Mo10O33 crystal structure. 48 nitrogen- or oxygen-containing compounds, that is, amines, carboxamides, sulfonamides, and ketones, were successfully synthesized through a borrowing-hydrogen mechanism. Up to 99% isolated yields were obtained under relatively mild conditions without additive organic ligand. The catalytic process shows promise for the efficient and economic synthesis of amine, carboxamide, sulfonamide, and ketone derivatives because of the simplicity of the system and ease of operation. Copyright
Fe(II)-catalyzed N-alkylation of sulfonamides with benzylic alcohols
Cui, Xinjiang,Shi, Feng,Zhang, Yan,Deng, Youquan
supporting information; experimental part, p. 2048 - 2051 (2010/06/16)
The FeCl2/K2CO3 catalyst system was developed successfully for the N-alkylation of sulfonamides with benzylic alcohols via borrowing hydrogen method. XPS analysis suggested a possible catalyst cycle between Fe(II) and Fe(0). Under the optimized condition, the scope of the protocol was demonstrated in 21 different alkylation reactions. High yields, in general >90%, are achieved in most cases.
Copper-catalyzed alkylation of sulfonamides with alcohols
Shi, Feng,Tse, Man Kin,Cui, Xinjiang,Goerdes, Dirk,Michalik, Dirk,Thurow, Kerstin,Deng, Youquan,Beller, Matthias
supporting information; experimental part, p. 5912 - 5915 (2009/12/08)
Water is the only by-product in an efficient and atom-economical Cu(OAc)2-catalyzed coupling of alcohols with sulfonamides (see proposed mechanism; Ts= p-toluenesulfonyl). It was discovered that bissulfonylated amidines formed as intermediates when the transhydrogenative C-N bond-forming reaction is carried out in air act as novel ligands to stabilize the catalyst.
