Base-Induced Dehydrogenative and Dearomative Transformation of 1‑Naphthylmethylamines to 1,4-Dihydronaphthalene-1-carbonitriles

Solvothermal treatment of 1-naphthylmethylamine with
potassium
hydride (KH) or n-butyllithium (n-BuLi)–potassium t-butoxide (t-BuOK) in THF induces unusual two consecutive β-hydride eliminations
to form 1-naphthonitrile and KH. The freshly generated KH is hydridic
enough to undergo dearomative hydride addition to the resultant 1-naphthonitrile
regioselectively at the C4 position to afford α-cyano benzylic
carbanion, which could be functionalized by a series of electrophiles,
liberating the corresponding 1,4-dihydronaphthalene-1-carbonitriles
having a quaternary carbon center.