Furan ring opening - isocoumarine ring closure: A recyclization reaction of 2-carboxyaryldifurylmethanes
作者:Vladimir T. Abaev、Artem S. Dmitriev、Sergey A. Podelyakin、Alexander V. Butin、Andrey V. Gutnov
DOI:10.1002/jhet.5570430510
日期:2006.9
A general method for the synthesis of isocoumarine derivatives has been developed. Bis(5-R-2-furyl)methylbenzoic acids (R = methyl, ethyl) underwent recyclization and subsequent cyclization into tetracyclic isochromene-1-one derivatives under treatment with hydrogen chloride in methanol. It has been shown that intermediate 4-(5-R-furan-2-yl)-3-(3-oxo-3-R-propyl)-isochromene-1-ones can be obtained selectively
The novel 4,10-dihydro-3H-pyridazino[1,6-b]isoquinolin-10-one heterocyclic system was synthesized by acid-catalyzed recyclization of 2-(difurylmethyl)benzohydrazides as well as by recyclization of (2-carboxyaryl)difurylmethanes to isocoumarins followed by the reaction with hydrazine hydrate.