The mechanism of the Leuckartreaction of 3,3- and 7,7-dimethyl-2-oxo-1-norbornyl triflates and triflamides, synthesised by us starting from (1R)-camphor and (1R)-fenchone, has been studied. Strikingly, the electron-withdrawing capacity of the bridgehead substituents has demonstrated not to be enough to control the Wagner–Meerwein rearrangement during the course of the reaction, so that only both enantiomers
Enantiospecific synthesis of substituted bicyclo[2.1.1]hexane-1-carboxylic acids and esters
作者:A.García Martínez、E.Teso Vilar、J.Osío Barcina、M.E.Rodriguez Herrero、S.de la Moya Cerero、M. Hanack、L.R. Subramanian
DOI:10.1016/s0957-4166(00)80096-8
日期:1993.11
The base promoted ringcontraction of the readily accessible homochiral 2-oxo-1-norbornyl inflates 3 in 60% ethanol takes place with formation of bicyclo[2.1.1]hexane (4a), (+)- or (−)-7,7-dimethyl-bicyclo[2.1.1]hexan-1-carboxylic acids (4c or 4b) and the corresponding ethyl esters in good yields.