Ck. Ghosh et al., BENZOPYRANS .29. REACTIONS OF SOME SIMPLE CONDENSATES OF 4-OXO-4H-1-BENZOPYRAN-3-CARBOXALDEHYDE WITH NITROGEN NUCLEOPHILES, Indian journal of chemistry. Sect. B: organic chemistry, including medical chemistry, 32(6), 1993, pp. 624-629
The chromone 2, derived from the title aldehyde 1, gives the pyrazole
8 (R3 = Ph) with phenylhydrazine whereas 5 gives with H2NNHR3 (R3 = H
and Ph) the pyridine derivatives (9). Hydroxylamine converts the chrom
ones 24 into pyridine-1-oxides (13-15), respectively. The reaction of
1 with ethyl glycinate in the presence of pyridine affords the pyrrole
s 20 and 21, the former (20) being detected in the product mixture der
ived from 4 and ethyl glycinate.