Microwave assisted synthesis of mono- and bis-phenylhydrazones of l-threo- and d-erythro-2, 3- hexodiulosono-1, 4-lactones for the synthesis of an array of heterocyclic compounds

الملخص EN

Microwave assisted organic synthesis (MAOS) and organic reaction enhancement (MORE) for the conversion L-ascorbic acid (1) and D-is ascorbic acid (2) to various heterocyclic compounds via their monophenylhydrazones 3 and 4 and bis (phenylhydrazones) 7 and 8 have been achieved.

Acetic anhydride converted 3 and 4 to the olefinic compound 6 and their oximes 11 and 12 to 4-(L-threo-2, 3-diacetoxy- (1-hydroxypropyl-2-phenyl-1, 2, 3 -triazole-5-carboxylic acid lactone (14).

Treatment of 7 and 8 with alcoholic cupric chloride gave 15 which can be acetylated to 5-O-acetyl-3,6-anhydro-3-phenylazo-L-xylo-2-hexulosono-1,4-lactone phenylhydrazone (16) and degraded to 1-(2-phenylhydrazide)-2-(2-phenylhydrazone) mesoxalic acid (17) They were transformed to 1-phenyl-3-(L-throe or D-erythro-glycerol-1-yl)-pyrazoline-4, 5- done phenylhydrazone 18 and 19 whose degradation afforded 3-carboxaldehyde-1-phenyl pyrazoline -5, -4 dione 4-phenylhydrazone (22).

All the reactions using MW gave cleaner, faster and similar or higher yields of products.