Pyridine → 7-Methoxynaphthalene-1-carbonitrile

Participants

Reaction Conditions

Reaction Steps

7-Methoxy-1-tetralone (8.16 g, 46 mmol, 1 eq) and ZnI2 (0.365 g, 1 mmol, 0.025 eq) were dissolved in 25 ml of toluene and heated at 45° C. Trimethylsilylcyanide (TMSCN) (5.0 g, 50 mmol, 1.1 eq) is added over a period of 20 min, and all is refluxed for 3 h. After cooling the mixture at about 35° C., pyridine (5.5 ml, 69 mmol, 1.5 eq) and POCl3 (6.4 ml, 69 mmol, 1.5 eq) are added, and the mixture is boiled under reflux for another 6 h. Thereafter, 80 ml of a 3 N NaOH cooled at 3° C. is added over a period of 15 min. The aqueous phase is extracted with 48 ml of toluene, and the organic phase is washed twice with 40 ml of 1 N NaOH, once with 40 ml of water, three times with 40 ml of 3 N HCl, once with 40 ml of water, once with 40 ml of a saturated NaHCO3 solution and once with a saturated sodium chloride solution. After the addition of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (8.41 g, 37 mmol, 0.8 eq) over 20 min, the organic phase is boiled under reflux for 2 h. After cooling, the precipitate was filtered off and washed twice with 32 ml of 1 N NaOH and once with 32 ml of a saturated sodium chloride solution. Drying of the precipitate yielded the desired product in a yield of 78%, 6.6 g.

Provenance & Evidence