3-Unsaturated alkyl cephems from 3-triflyl cephems

A process for the production of a cephem derivative represented by the formula ##STR31## wherein R.sup.1 represents a group selected from unsubstituted and substituted 1-alkenyl, conjugated and unconjugated 1-polyalkenyl, 1-alkynyl, aryl or heteroaryl selected from phenyl, 2-, 3-, or 4-pyridyl and -pyridylmethyl, 2-imidazolyl and -imidazolylmethyl, 2-thiazolyl and -thiazolylmethyl, 2-, or 3-furyl and -furylmethyl, 2-pyrryl and -pyrrylmethyl, 2-thienyl and -thienylmethyl;

• wherein Q represents a group selected form H, t-butyloxycarbonyl, a silyl protecting group, or the acyl group of a known 7-acylamino cephalosporin antibiotic and the aryl, and heteroaryl groups may be substituted with 1 to 3 alkyl, hydroxy, alkoxy, halo, amino, mono- and dialkylamino, nitro, carboxyl, alkoxcarbonyl, and cyano groups and pharmaceutically acceptable acid addition and base salts and esters thereon, comprising the steps of:
• (a) providing a 3-trifluoromethanesulfonyloxy-3-cephem starting compound in a relatively polar aprotic solvent;
• (b) contacting the starting compound from step (a) above with at least an equimolar amount of R.sup.1 -trialkyl-stannane in the presence of about 1-10 mole % of a pd(0) and Pd(II) compound and about 3-30 mole % of tri-(2-furyl)-phosphine at 25-65? C., protected from atmospheric oxygen, for 1-75 hrs, and
• (c) recovery of the cephem product from the reaction step (b).