80067-73-8Relevant articles and documents
Reactions de dicycloaddition des ortho-dihydroxymethyl diphenols. I. Synthese et structure de tetrahydrobenzodipyrannes
Lanteri, Pierre,Langin-Lanteri, Marie-Therese,Longeray, Remi
, p. 103 - 112 (2007/10/02)
It is now well known that saligenol is a potential diene for Diels-Alder reactions.We have prepared saligenol analogues such as 1 and 2 with two orthohydroxymethylphenol groups, in order to find out if a double cycloaddition is possible. 1, 2 First we have submitted compound 1 to thermal conditions of reaction with some dienophiles, but the yields were too low because of competitive polymerisations.We therefore preferred to explore as completely as possible the cycloaddition reaction of compounds 1 and 2 performed under acid catalysis.In these conditions, tetrahydrobenzodipyrans 3 and 4 were isolated with yields depending on the nature of the dienophile used in the reaction: 3, 4, Most of the compounds 3 and 4 are mixtures of isomers, and only in two cases we were able to isolate the resulting diastereoisomers.Although the yields are sometimes low, this one-step synthesis should be of interest owing to the fact that tetrahydrobenzodipyrans such as 3 and 4 are seldom described in the literature and, in most cases, require several steps for their synthesis.
