“…(CDCh) 5.24 (s, 2 ), 1.7-3.0 (m, 9 H), and 0.2 (s, 1 H). Treatment of 40 mg of -benzoyl-o-tolualdehyde with methanol at room temperature for 3 h in the presence of a trace of acid afforded a quantitative yield of 1 -methoxy-3-phenyi-1 //-2-benzopyran (25). When this compound was allowed to stand in the presence of methanol for an additional 5 h it was partially converted to a-benzoyl-o-tolualdehyde dimethylacetal.…”