Racemates of cis- and trans-2-(N(β)-t-butoxycarbonyl-N(α)- methylhydrazino)cyclopentanols and -cyclohexanols 1-4 were resolved through lipase PS- or Novozym 435-catalysed asymmetric acylation of the secondary OH group at the (R)-stereogenic centre. High enantioselectivity (E >200) was observed when vinyl acetate or vinyl butyrate was used in diisopropyl ether, resulting in the enantiopure hydrazino esters 1a-4a and hydrazino alcohols 1b-4b. Methanolysis of the esters 1a-4a afforded the corresponding 2- hydrazinocycloalkanols 1c-4c (ee usually >95%). (C) 1999 Elsevier Science Ltd.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry