Dimethylamine → Diethyl ((3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl)methyl)phosphonate

Participants

Reaction Conditions

Reaction Steps

20.63 g (100 mmol) of 2,6-di-tert-butylphenol, 5.22 g (174 mmol) of paraformaldehyde, 6.1 g (45 mmol) of 33% ethanolic dimethylamine and 26 ml (=24.7 g) of N,N-dimethylformamide are heated at 50° C. under nitrogen for 1 hour in a sulfonation flask fitted with a reflux condenser and mechanical stirrer. 33.23 g (200 mmol) of triethyl phosphite are added to this mixture. It is heated under reflux at a reaction temperature of 105° C.; the conversion to the final product is 82% (HPLC). Working-up: extraction (water/methylcyclohexane) and recrystallization (methylcyclohexane). Yield: 23.0 g (65%), melting point 120° C., purity (HPLC): 98%.

Provenance & Evidence