R. Uddin et A. Zaman, REACTIONS OF 3-BROMOCHROMONE WITH ENAMINE AND ENOL, Indian journal of chemistry. Sect. B: organic chemistry, including medical chemistry, 34(7), 1995, pp. 639-640
3-Bromochromone on reaction with 1-methyl (or phenyl) amino-1-methyl-t
hio-2-nitroethylene gives the pyrrole (3,R' = H, or CH3, R(2) = Me or
Ph) while furopyran (5, R = H or CH3) is obtained with triacetic acid
lactone (4).