Enantioselective synthesis of 3-substituted 1-azabicyclo (2.2.1) heptanes

摘要

A process for preparing a substantially pure enantiomer of a compound formula (I) ##STR1## wherein X is O or S; andPPR. sup.2 represents hydrogen, --CF.sub.3, --OR.sup.7, --SR.sup.7, --NR.sup.7 R.sup. 8, --CN, --COOR.sup.7, --CONR.sup.7 R.sup.8, or a saturated or unsaturated, substituted or unsubstituted hydrocarbon group, wherein R. sup.7 and R.sup.8 are independently selected from hydrogen and C.sub.1-2 alkyl provided that --NR.sup.7 R.sup.8 is other than NH.sub.2 ;P Pwhich process comprises cyclization of a compound of formula (10) or salt thereof: ##STR2## wherein X and R.sup.2 are as defined in formula (I); and R.sup.4 is a labile leaving group and optionally epimerizing the endo-diastereomer so prepared to produce the corresponding exo-diastereomer.