Lewis acid mediated nucleophilic substitution reactions of 2-alkoxy-3, 4-dihydro-2H-1-benzopyrans: regiochemistry and utility in the synthesis of 3, 4-dihydro-2H-1- …
The Lewis acid mediated nucleophilic substitution reactions of a variety of 2-alkoxy-, 2- hydroxy-, and 2-(acyloxy)-3, 4-dihydro-2H-l-benzopyrans (chromans) have been studied within the context of developing new synthetic routes to chroman-2-carboxylic acids, certain of which have utility as antioxidants and drug intermediates. The scope and limitations of these transformations have been determined. Treatment of 2-methoxychromans in the a- ...
