New chemical access for pyran core embedded derivatives from bisalkenylated 1, 3-diketones and 1, 3-diketoesters via tandem C-dealkenylation and cyclization
New chemical access has been developed for the synthesis of pyran core embedded derivatives from 1, 3-diketones and 1, 3-diketoesters, in which the active methylene group of 1, 3-diketone or 1, 3-diketoester was alkenylated with three equivalents of alkenyl bromides in presence NaH to give bisalkenyl 1, 3-diketones or 1, 3-diketoesters and the resultant bisalkenyl 1, 3-diketones or 1, 3-diketoesters were reacted with AlCl3 at room temperature ...