An Efficient One-Step Synthesis of Piperidin-2-yl and Pyrrolidin-2-yl Flavonoid Alkaloids through Phenolic Mannich Reactions
作者:Thanh Binh Nguyen、Qian Wang、Françoise Guéritte
DOI:10.1002/ejoc.201101312
日期:2011.12
An efficient one-stepsynthesis of piperidin-2-yl and pyrrolidin-2-yl flavonoid alkaloids was achieved in good to excellent yields by a highly regioselective phenolic Mannich reaction of chrysin with cyclic imines or iminium salts. Performing the reaction in a mixture of H2O/THF in the absence of an external reagent afforded the C-6 alkylated product exclusively. The same reaction in water in the presence