Studies on Oxasteroids. I. Synthesis of 3-Cyano-3-methylchroman-4-one.

Condensation of chroman-4-one with ethyl formate in the presence of sodium methoxide gave 3-hydroxymethylenechroman-4-one (II). Reaction of II with hydroxylamine hydrochloride, followed isomerization by potassium t-butoxide gave IV. 3-Cyano-3-methylchroman-4-one was obtained by methylation of IV or treatment of III with potassium t-butoxide and methyl iodide