Síntese de derivados de dihidronafto[c]furanos e fenantrenos via processo de carbociclização intramolecular

Abstract

n this work, we reported the study developed for the preparation of substituted dihydronaphtho[c]furans and phenanthrenes via intramolecular cyclization process. Firstly, a variety of dihydronaphtho[c]furans 2 was prepared by the reaction of bis-propargyl ethers 1 with a catalytic amount of t-BuOK. Subsequently, the o-ethynyl-biphenyls 3 were subjected to carbocyclization reaction mediated by I2 and a catalytic amount of K2CO3, which allowed the synthesis of 9-iodo-10-organochalcogen-phenanthrenes 4. Yet, the o-ethynyl-biphenyls 3 carbocyclization reaction promoted by diorganyl diselenides and FeCl3, lead to 9- organochalcogen-phenanthrenes 5. The methodologies proceeded selectively, furnishing the products in good yields under mild reactions conditions.