Formaldehyde → HCID 131729393, compound

Participants

Reaction Steps

N-(3,4-dichlorophenethyl)-2,2,2-trifluoroacetamide (2.860 g, 10.0 mmol) and paraformaldehyde (453 mg, 15.1 mmol) were placed in a round-bottom flask. A mixture composed of H2SO4 (20 mL) and AcOH (13 mL) was added at room temperature in one portion. The reaction mixture was stirred for 8 h at room temperature. The mixture was poured into ice-water (230 mL) and extracted with EtOAc (3×40 mL). The organic phases were combined, washed with water (25 mL), aqueous saturated NaHCO3 (25 mL), brine (25 mL), and then dried over sodium sulfate, filtered, and concentrated. The residue obtained was purified by silica gel column chromatography (gradient 1-45% EtOAc in hexanes, 120 g) providing 6,7-dichloro-3,4-dihydroisoquinoline-N-trifluoroacetamide (1.3 g, 44%) and 7,8-dichloro-3,4-dihydroisoquinoline-N-trifluoroacetamide (652 mg, 22%) as mixture of products (ratio was determined by NMR). LC/MS ((10%-99% CH3CN (0.035% TFA)/H2O (0.05% TFA)), m/z: M+1 obs=298.3; tR=1.95 min.

Provenance & Evidence