Synthetic approaches towards benzo[h]quinoline-3-carbonitriles

2-Alkoxybenzo[h]quinoline-3-carbonitriles 2 were readily synthesized via Di mroth rearrangement of 2-amino-4-aryl-5,6-dihydro-4H-naphtho[1,2-b]pyran-3- carbontriles 5 induced by ethanolic and methanolic KOH. Compounds 2 were al so obtained by the reaction of 2-arylmethylidene-3,4-dihydro-1(2H)-naphthal enones 1 with malononitrile or of ylidenemalononitriles 4 with 1,2,3,4-tetr ahydro-1-naphthalenone in ethanolic and methanolic KOH. The molluscicidal a ctivity of the products towards Biomphalaria alexandrina snails was screene d.