Versatile approach to heteroarylfuroxan derivatives from oximinofuroxans via a one-pot, nitration/thermolysis/[3+2]-cycloaddition cascade. Issue 42 (18th October 2017) - Larin, Alexander A.
Graphical abstract: Highlights: The cycloaddition reactions of furoxancarbonitrile oxides have been performed. This approach enables to obtain various N, O -heteroarylsubstituted furoxans. Target heteroarylfuroxans are formed in good yields with high regioselectivity. Abstract: A simple, general, and regioselective method has been developed for the synthesis of a series of heteroarylfuroxans, including isoxazolyl-, isoxazolinyl- and (1, 2, 4-oxadiazolyl)furoxans. The described method is based on a cascade of one-pot processes, including the nitration of furoxancarbaldehyde oximes, thermolysis of the formed nitrolic acids to generate furoxancarbonitrile oxides, and [3+2]-cycloaddition with an appropriate dipolarophile – alkynes, olefins, or activated nitriles.