THE SYNTHESIS OF 3-NITRO-4<i>H</i>-BENZO[<i>h</i>]CHROMENES
DOI:
https://doi.org/10.1007/7565Keywords:
1-naphthoquinone 2-methides, 3-nitro-4H-benzo[h]chromenes, 4-(2-nitrovinyl)morpholine, Mannich bases, push-pull olefins, Diels–Alder reaction, Michael reaction.Abstract
A method for the synthesis of 3-nitro-4H-benzo[h]chromenes was developed based on the reaction of 1-naphthoquinone 2-methides generated in situ from Mannich bases with 4-(2-nitrovinyl)morpholine. It was shown that such nucleophiles as morpholine and 4-bromoaniline add to the double bond of the pyran ring.