An Efficient Synthesis of 3-(1H-Tetrazol-5-yl)coumarins (=3-(1H-Tetrazol-5-yl)-2H-1-benzopyran-2-ones) via Domino Knoevenagel Condensation, Pinner Reaction, and 1,3-Dipolar Cycloaddition in Water
A novel straightforward synthesis of 3‐(1H‐tetrazol‐5‐yl)coumarins (=3‐(1H‐tetrazol‐5‐yl)‐2H‐1‐benzopyran‐2‐ones) 6 viadominoKnoevenagelcondensation, Pinnerreaction, and 1,3‐dipolar cycloaddition of substituted salicylaldehydes (=2‐hydroxybenzaldehydes), malononitrile (propanedinitrile), and sodium azide in H2O is reported (Scheme 1 and Table 2). This general protocol provides a wide variety of