Solid Phase Baker–Venkataraman rearrangement under solvent-free condition using grinding technique

摘要

Baker–Venkataraman rearrangement of 2-aryloxyacetophenones and 2-cinnamoyloxyacetophenones to 2-hydroxydibenzoylmethanes and 2-hydroxybenzoylcinnamoylmethanes is the key step in the synthesis of flavones and 2-styrylchromones, a class of naturally occurring compounds and several other benzofuranone derivatives. A very simple and highly efficient eco-friendly procedure for Baker–Venkataraman rearrangement has now been developed which involves the grinding of 2-aryloxyacetophenones/2-cinnamoyloxyacetophenones with pulverized potassium hydroxide in a mortar by a pestle and avoids the use of organic solvents at any stage of the reaction.