Abstract
Novel chromonyl phosphonic acid 3, diethyl chromonyl phosphonate 4, and diethyl chromonyl pyridinyl phosphonate 5 were obtained from treatment of 2-cyano-3-(4-oxo-4H-chromen-3-yl) prop-2-enamide (2) with phosphorous acid and its diesters. Also, an efficient route to functionalized phosphorus heterocycles such as 1,2,3-diazaphosphinane, 1,2,3-thiazaphosphinine and 1,2-azaphosphole bearing a chromone ring was achieved via reaction of compound 2 with some phosphorus sulfides and phosphorus tribromide. A key part of the reaction mechanisms is discussed. Structures of the new synthesized products were established on the basis of spectral data (IR, ESI-MS, H-1-, C-13 and P-31-NMR spectra).
An efficient route to functionalized phosphorus heterocycles such as 1,2,3-diazaphosphinane, 1,2,3-thiazaphosphinine and 1,2-azaphosphole bearing a chromone ring was achieved via reaction of 2-cyano-3-(4-oxo-4H-chromen-3-yl)prop-2-enamide with some phosphorus sulfides and phosphorus tribromide.
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