Thermal [4 + 2] cycloadditions of 3-acetyl-, 3-carbamoyl-, and 3-ethoxycarbonyl-coumarins with 2,3-dimethyl-1,3-butadiene under solventless conditions: a structural study.
نویسندگان
چکیده
The thermal [4+2] cycloadditions of 3-acetyl-, 3-carbamoyl, and 3-ethoxycarbonylcoumarins with 2,3-dimethyl-1,3-butadiene under solvent free conditions are reported, as well as the epoxidation reactions of some adducts. Discussion is focused on the structural features of the Diels-Alder adducts and their epoxides, based upon NMR, X-ray, and mass spectral data, and supported by ab initio theoretical calculations.
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ورودعنوان ژورنال:
- Molecules
دوره 15 3 شماره
صفحات -
تاریخ انتشار 2010