Possible directions of the reactions of different structural type 2-hydroxynaphthazarins with triethers of orthocarboxylic acids. V.L. NOVIKOV, N.N. BALANEVA, O.P. SHESTAK, V.P. GLAZUNOV

Abstract

Analysis of the possible mechanisms of thermal reactions of 2-hydroxynaphthazarins, containing or not containing
the substituents at the position 3, with triethers of orthocarboxylic acids gave an explanation for the facts why the reactions of trimethyl and triethyl orthoformates with substituted at C-3 substrates lead to the formation of O-alkyl ethers, whereas the reactions with unsubstituted at C-3 substrates provide the mixtures of dibenzo[b,h]xanthentetraones and tris-(2-hydroxy-1,4-naphthoquinon-3-yl)methanes. In the case of trimethyl orthoacetate, an explanation why its reactions with substrates of any one structural type produce only O-methyl ether was provided.