Verfahren zur Herstellung von Cephalosporin-Derivaten

摘要

The present invention is concerned with a novel process for the manufacture of cephalosporin derivatives of the general formula wherein R<1>, R<2> and R are defined in the specification, the process is characterized in that it comprises converting a phosphonium salt of the general formula wherein R is as above and Ph represents phenyl, into the corresponding ylide of the general formula wherein R and Ph are as above, and reacting same with an aldehyde of the general formula wherein R<1> and R<2> are as above.