N-Tosylhydrazones: versatile synthons in the construction of cyclic compounds
1Beijing National Laboratory of Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China. wangjb@pku.edu.cn.
Abstract:
N-Tosylhydrazones have recently emerged as useful synthons in a variety of transition-metal-catalyzed and transition-metal-free reactions, which affords novel methodologies for the formation of carbon-carbon and carbon-heteroatom bonds. In this context, it has been found that N-tosylhydrazones can be used as versatile building blocks in the construction of a range of cyclic compounds. In this review, cyclization reactions based on N-tosylhydrazones as substrates are discussed. A series of cyclic compounds, including aromatic and non-aromatic ring systems, are demonstrated to be easily constructed by cyclizations with N-tosylhydrazones.
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