| abstract |
The invention relates to a process for the preparation of 3-amino-2-benzoyl-acrylic acid derivatives of the formula I in which R1, R2, R3, X, X1, X2 and X3 have the meaning given in the description by reacting benzoyl halides of the formula II with 3-Aminoacrylsaeurederaten the formula III. The compounds of formula I are intermediates for the preparation of antibacterial drugs. Compared to the processes known from the prior art, the process according to the invention has the advantage that only the C-acylation of the enamine system takes place, which leads to a considerable increase in yield. Formulas I, II, III |