Ammonium Chloride → 1-(2,3-Dichlorophenyl)ethanol

Beteiligte Stoffe

Reaktionsschritte

Iodomethane (324.89 g, 2.288 mol) was added dropwise, with stirring, to magnesium turnings (54.88 g, 2.288 mol) in dry ether (1 liter), to form methyl magnesium iodide. 2,3-Dichlorobenzaldehyde (200 g, 1.144 mol) dissolved in benzene/diethyl ether (1 liter, 50:50) solution was added dropwise, with stirring, to the Grignard. The reaction mixture was allowed to stir at room temperature overnight. The solution was refluxed for 2 hours, and then allowed to cool. The reaction mixture was poured into saturated ammonium chloride solution (5 liters) and the organic layer separated. The aqueous layer was extracted with ether (3×2 liters). The organic phases were combined, washed with brine (1×2 liters), dried over anhydrous magnesium sulphate, filtered and evaporated down. α-Methyl-2,3-dichlorobenzyl alcohol (196.4 g, 90% yield) was obtained as a yellow oil which crystallised on standing to give a pale-yellow solid. T.l.c. (SiO2 ;CHCl3) showed no impurities so no further purification was carried out. However, if necessary the alcohol nay be recrystallised from 40-60° C. petroleum ether to afford white prisms of melting point 53° C.

Herkunft & Nachweise