A convenient general synthesis of 3-substituted 2H-chromene derivatives
作者:Perry T Kaye、Xolani W. Nocanda
DOI:10.1039/b201827f
日期:2002.5.10
Reactions of 2-hydroxybenzaldehydes and 2-hydroxy-1-naphthaldehydes with various activated alkenes under Baylis–Hillman conditions have been shown to proceed with regioselective cyclisation to afford the corresponding 3-substituted chromene derivatives. In some cases competitive dimerisation of the alkene component was observed, and direct dimerisation in the absence of the aldehyde has been explored.
chromene-3-carbonitrile in ethanol under classical and microwave conditions is described. The threecomponent1,3-dipolarcycloaddition reaction proceeds via in situ generation of azomethine ylides by the decarboxylative condensation of indenoquinoxalone with proline/benzyl amine and their selectivity towards the endo cyclic double bonds of dipolarophile (chromene-3-carbonitrile) leading to the formation