Diversity-Oriented Synthesis of 3-Iodochromones and Heteroatom Analogues via ICl-Induced Cyclization
作者:Chengxiang Zhou、Anton V. Dubrovsky、Richard C. Larock
DOI:10.1021/jo0523722
日期:2006.2.1
The ICl-inducedcyclization of heteroatom-substituted alkynones provides a simple, highly efficient approach to various 3-iodochromones and analogues. This process is run under mild conditions, tolerates various functional groups, and generally provides chromones in good to excellent yields. Subsequent palladium-catalyzed transformations afford a rapid increase in molecular complexity and a convenient
New flavone derivatives to be used as analeptics having the formula ##STR1## wherein R.sub.1 and R.sub.2 are both methyl or ethyl, or taken together with the nitrogen atom to which they are attached represent a mononuclear 5- or -6 membered heterocyclic ring which may contain an oxygen atom as further hetero atom; R.sub.3 and R.sub.4 are hydrogen or methyl, provided that at least one of them is hydrogen, and process for the preparation thereof starting from resorcinol and phenylacetonitrile or a phenylacetonitrile derivative.