Jung, Michael E. Allen, Damian A. Use of 4-Cyanocoumarins as Dienophiles in a Facile Synthesis of Highly Substituted Dibenzopyranones A new synthesis of dibenzopyranones <b>14</b> is reported via the Dielsāˆ’Alder cycloaddition of 4-cyanocoumarins <b>12</b> with 1-silyloxydienes <b>10</b> to give the adducts <b>13</b> which are then converted into <b>14</b> in one step via treatment with base and loss of the cyano and silyloxy groups. silyloxy groups;cyano;silyloxydiene;Dienophile;dibenzopyranones 14;cycloaddition;adducts 13;Cyanocoumarin;Diel;cyanocoumarin;synthesis;Facile Synthesis;Substituted Dibenzopyranones 2009-02-05
    https://acs.figshare.com/articles/journal_contribution/Use_of_4_Cyanocoumarins_as_Dienophiles_in_a_Facile_Synthesis_of_Highly_Substituted_Dibenzopyranones/2880916
10.1021/ol802792g.s001