2-Cyano-6,11-dihydro-11-oxodibenz[b,e]oxepin → 2-Cyano-6,11-dihydro-11-ethylidenedibenz[b,e]oxepin

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Reaction Steps

Suspent 23.6 gm of ethyl triphenylphosphonium bromide in 200 ml of dry tetrahydrofuran add dropwise 2.4 ml of t-butyllithium in hexane with stirring at room temperature under a nitrogen atmosphere. Continue stirring for 3 hours and then cool to -70° C. in a dry ice bath. Add 10 gm. of 2-cyano-6,11-dihydro-11-oxodibenz[b,e]oxepin in 75 ml of dry tetrahydrofuran dropwise over 30 minutes. Continue stirring at -70° C. for 30 minutes, warm to room temperature and continue stirring overnight under a nitrogen atmosphere. Pour the mixture into 400 ml. of ether, filter and wash the filtrate with saturated aqueous sodium chloride solution. Dry over anhydrous magnesium sulfate and strip to dryness. Chromatograph the residue over silica gel, eluting with 5% ethyl acetate in hexane to obtain the final product (5.73 gm).

Provenance & Evidence