4-[(2-Methylbut-3-yn-2-yl)oxy]benzonitrile → 2,2-dimethyl-2H-1-benzopyran-6-carbonitrile

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Reaction Steps

Cyclisation of the 3-(p-cyanophenoxy)-3-methybut-1-yne (9.77 g) was accomplished by heating in diethylaniline at 210°-220° C. under nitrogen. Purification by distillation, and extraction with dilute hydrochloric acid gave 2,2-dimethyl-6-cyano-2H-benzo[b]pyran as a colourless oil (6.84 g), which slowly crystallised on standing, having a nmr spectrum showing signals at δ146, 6.25 (d, J=10), 5.67 (d, J=10), 6.74 (d, J=8), 7.18 (d, J=2), 7.34 (q, J=8,2).

Provenance & Evidence