1023247-22-4Relevant articles and documents
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.
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.
