Alkylation of tosylhydrazones

N,N-Methyltosylhydrazones. Ketones react only slowly with N,N-methyl-tosylhydrazine (1) but hydrazones of this type can be prepared by N-alkylation of tosylhydrazones with phase-transfer catalysis. The more reactive thioketones also react sluggishly with 1, but in this case, the reaction can be catalyzed by soft Lewis acids. Thus the reaction of 2 with 1 proceeds in high yield at room temperature in the presence of 1 equiv. of silver nitrate. Mercuric acetate also promotes this reaction, but the yield of 3 is only 50% because of formation also of 4 in 44% yield. 

RCHO —i- RCH R. This transformation can be accomplished by reductive alkylation of tosylhydrazones of aldehydes with alkyllithium reagents (equation... 

One reasonable pathway to unexpected ring-opened product 21 is shown below, although several variations can be written. Related types of alkylations of tosylhydrazones have been reported for other alkyllithium reagents. ... 

N-Alkylation of tosylhydrazones through phase transfer catalysis. S. Cacchi, F. LaTorre and D. Misiti, Synthesis, 301 (1977)... 

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See also in sourсe #XX -- [ ]

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