A new method for preparation of dihydrodinaphthopyranopyrans

Abstract

Abstract The syntheses of 7a,15a-dlhydro-15a-methylnaphtho[2,l-b] naphtho [1',2':5,6] pyrano[3,2-e]pyran (II) and 7a,15a-dihydro-7a-methyl-15a-isopropyi naphtho [2,1-b] naphtho [1' ,2' : 5,6] pyrano [3,2-e] pyran (III) from 2-naphthol and corresponding dimethylol ketones in one step were described. Amberlyst-15® was used as catalyst.