摘要 |
A process for the manufacture of compounds of formula I <CHEM> wherein A together with the two carbon atoms denoted as alpha and beta represents one of the groups <CHEM> R<1> represents cyano or a group of the formula -COOR<4>, R<2> represents hydrogen, R<3> represents lower alkyl, or R<2> and R<3> together signify a di- or trimethylene group, R<4> represents lower alkyl or benzyl; and R<5>, R<6> each signify hydrogen, halogen, trifluoromethyl, lower alkoxy or nitro and the carbon atom denoted by gamma has the S-configuration when R<2> is different from hydrogen which process comprises reacting a compound of the formula <CHEM> wherein A, R<2> and R<3> have the significance given above and X represent a halogen atom, in the presence of a base with a compound of the formula <CHEM> wherein R<7> is lower alkyl or cycloalkyl and R<1> has the significance given above. |