4-Aminopyridine catalyzed direct and regioselective acylation of N-tosylhydrazide
Kosuke Namba1, Isamu Shoji, Mugio Nishizawa
1Division of Chemistry, Graduate School of Science, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan. namba@mail.sci.hokudai.ac.jp
Abstract:
An efficient and simple method for selective acylation of either one of two nitrogen atoms of tosylhydrazide was developed. The selectivity was drastically controlled by a catalytic amount of 4-aminopyridine or 4-(dimethylamino)pyridine with common acylating agents. The nitrogen atom masked with a tosyl group was acylated in the presence of 4-aminopyridine, whereas the primary nitrogen atom was acylated in the absence of 4-aminopyridine.
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