34916-10-4

4-Cyanocyclohexanone is used to prepare nicotinamides as PDE4 D isoenzymes inhibitors. It is also used as an anthranilic acid replacement in niacin receptor agonist.

The general procedure for the synthesis of 4-oxocyclohexanecarbonitrile from 1,4-dioxaspiro[4.5]decane-8-carbonitrile was as follows: to a 5000 mL three-necked flask were added 200.6 g (1.2 mol) of 1,4-dioxaspiro[4.5]decane-8-carbonitrile, 72 g (1.2 mol) of boric acid, 2000 mL (10 vol. eq.) of water and hydrochloric acid. Subsequently, 1000 mL (5 vol. eq.) of tetrahydrofuran and 500 mL (2.5 vol. eq.) of water were added, and the mixture was heated to 60°C. The reaction lasted for 2 hours. Samples were taken during the reaction and the progress of the reaction was monitored by gas chromatography (GC). The reaction was considered complete when the amount of remaining feedstock was less than 2%. The reaction mixture was cooled to room temperature and extracted by adding dichloromethane, which was repeated three times. The dichloromethane layers were combined and the solvent was removed by distillation under reduced pressure. Finally, the product was subjected to distillation at 100 °C and 2 mmHg to give 140.4 g of 4-oxocyclohexanecarbonitrile with 98% GC purity and 95% yield.

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