摘要 |
FIELD: organic chemistry, chemical technology. ^ SUBSTANCE: invention relates to a method for synthesis of compound of the formula (I): wherein R1 represents para-nitrobenzyl or allyl; X represents halogen atom. Method involves: (1) interaction of compound of the formula (IVa): wherein R1 represents para-nitrobenzyl or allyl, and R2 represents benzyl or substituted benzyl with P(OR3)3 in a solvent medium to yield compound of the formula (III): wherein R1 represents para-nitrobenzyl or allyl; R2 represents benzyl or substituted benzyl; R3 represents (C1-C6)-alkyl and (2) the following heating compound of the formula (III) in a solvent in the presence of LiCl and organic soluble base to form compound of the formula (II): wherein R1 represents para-nitrobenzyl or allyl; R2 represents benzyl or substituted benzyl, and (3) interaction of compound of the formula (II) with R4-OH and PX5 to form compounds of the formula (I) that is an intermediate compound in synthesis of cephalosporin. ^ EFFECT: improved method of synthesis. ^ 14 cl, 5 ex |