Investigation of 4-acetyl-2,6-dibenzyl-1,5-dihydroxy-2-methylcyclohexa-4,6-dien-3-one by X-ray crystallography and H-1-NMR spectroscopy

Benzylation of 3-methylphloracetophenone [1-(2,4,6-trihydroxy-3-methylpheny l) ethanone] (3) with benzyl chloride gave 4-acetyl-2,6-dibenzyl-1,5-dihydr oxy-2-methylcyclohexa-4,6-dien-3-one (5). Compound 5 crystallizes in the or thorhombic space group Fdd2 with a = 17.586(2), b = 42.891(5), c = 10.279(2 ) Angstrom, V = 7753(2) Angstrom,(3) and Z = 16. When crystals of 5 were di ssolved in [D-6]acetone the compound underwent tautomerization and a mixtur e of 5 and its keto form 4 was obtained (keto form/enol form ratio 1:4).