Ammonium Chloride → HCID 76677914, compound

Participants

Reaction Steps

To a solution of 3-thiophene carboxaldehyde oxime (8 g, 62.9 mmol) in DMF (80 ml) is added N-chlorosuccinimide (8.8 g, 66 mmol) portionwise, while maintaining the reaction temperature below 45° C. On complete addition, the mixture is stirred one hour at room temperature before being poured into a saturated aqueous NH4Cl solution. The mixture is extracted with ethyl acetate. The organic layer is washed successively with water and brine, dried (MgSO4), filtered and concentrated. The residue and 5-methyltetrazole (5.3 g, 62.9 mmol) are diluted in dichloromethane (80 ml) and treithylamine (11.4 ml, 82.1 mmol) is added dropwise at room temperature. After stirring overnight, a saturated aqueous NH4Cl solution is added. The aqueous layer is extracted with ethyl acetate. The combined organic layers are washed successively with water and brine, dried (MgSO4), filtered and concentrated. Silica-gel chromatography of the residue affords 5.5 g of 5-methyl-1-(3-thiophenecarbohydroximoyl)-tetrazole [yield 37.6%; 1H-NMR (DMSO-d6) δppm: 2.48 (s, 3H), 7.42 (d, 1H), 7.51 (d, 1H), 7.74 (dd, 1H), 12.7 (s, 1H)] and 2 g 5-methyl-2-(3-thiophenecarbohydroximoyl)-tetrazole [yield 13.7%; 1H-NMR (DMSO-d6) δppm: 2.62 (s, 3H), 7.40 (m, 2H), 7.73 (dd, 1H), 12.6 (s, 1H)].

Provenance & Evidence