Synthetic studies on the key component of the new generation of quinolonecarboxylic acid, DU-6859. 1. Synthesis of (1R, 2S)-2-fluorocyclopropylamine by the use of …
…, T Katoh, K Nakatani, M Kamada, I Hayakawa, T Akiba…
The title synthesis was achieved by employing highly cis-selective cyclopropanation of N- benzyl-N-vinylcarbamates with zinc-monofluorocarbenoid, deprotection of the formed N- benzyl-N-(cis-2-fluorocyclopropyl) carbamates, and optical resolution of the resulting dl-cis-2- fluorocyclopropylamine by the use of l-menthyl chloroformate as a resolving agent. The cis- selectivity observed for the key cyclopropanation could be explained by the bent transition ...