-4,5-O-ISOPROPYLIDENE CYCLOPENT-2-EN-1-ONE SYNTHESIS METHOD Russian patent published in 2010 - IPC C07D317/44 

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry, specifically to a (4S,5S)-4,5-O-isopropylidene cyclopent-2-en-1-one synthesis method which involves reaction of methyl-5-desoxy-4-methylidene-2,3-isopropylidene-β-D-ribofuranoside, obtained through iodination of methyl-2,3-O-isopropylidene -β-D-ribofuranoside with a iodine-triphenylphophine complex in the presence of imidazole and then dehyro-iodination using diazabicycloundecene, with 1.5 equivalents of I2 in a solution of tetrahydrofuran-water (3:1, v/v) at room temperature for 5 minutes with subsequent treatment of the mixture of formed iodine hydrins with 5-8 equivalents of zinc dust while boiling in benzene and extraction of the desired product through re-crystallisation from petroleum ether (boiling point of 40-70°C). This method avoids use of scarce, expensive and toxic reagents, low temperature, material and labour input in steps for chromatographic purification of intermediate iodine hydrins and the end product and increases overall output of the desired product (46-48.5%) (compared to 17.7% in the standard) from the initial methyl-2,3-O- isopropylidene -β-D-ribofuranoside.

EFFECT: obtained compound can be used as a chiral synthon in streamlined synthesis of biologically active compounds.

1 cl, 1 ex