PROCESS FOR THE PREPARATION OF METHYL-METHYL-3, 4-DIHYDRO-2H-PYRAN-5-CARBOXYLATE

摘要

The present invention provides an improved process for the preparation of methyl-methyl-3,4-dihydro-2H-pyran-5-carboxylate of formula (IV), comprising the steps of: (IV) (i) alkylating 1-Bromo-3-chloropropane of formula (I) with Methylacetoacetate of formula (II) to prepare haloketone of formula (VII) in presence of an alcoholic solvent; (I) (II) (VII) (ii) O-alkylating the compound of formula (VII) with sodium methoxide to obtain the desired molecule methyl-methyl-3,4-dihydro-2H-pyran-5-carboxylate of formula (IV) in its crude form; (VII) (IV) (iii) Purifying the content of step (ii) above by fractional distillation to obtain the purified molecule of formula (IV).