Novel methods for the synthesis of 2-2-dimethylchromens
Abstract
2,2-Dimethylchromens are synthesised by pyridine-catalysed condensation of 3-hydroxyisovaleraldehyde dimethyl acetal (or 3-methylcrotonaldehyde) with appropriate phenols, and, among other examples, the method is applied to lonchocarpin, evodionol 7-methyl ether, jacacreubin, and acronycine.