2,3-DICHLORO-6-FLUOROBENZYL ALCOHOL synthesis

Yield:-

Reaction Conditions:

Stage #1: 2,3-Dichloro-6-fluorobenzaldehydewith sodium tetrahydroborate in ethanol at 10; for 0.333333 h;
Stage #2: with acetic acid in ethanol;

Steps:

1.a

a) (2,3-Dichloro-6-fluorophenyl)methanol; A solution of 2,3-dichloro-6-fluoro-benzaldehyde (80 g) in ethanol (250 ml) was added dropwise to a stirred suspension of sodium borohydride (7.8 g) in ethanol (150 ml) at a rate that maintained the internal reaction temperature below 10 °C. After complete addition, approximately 20 minutes, the mixture was allowed to reach ambient temperature. The mixture was evaporated to -1/4 volume and brine (200 ml) plus acetic acid (5 ml) was added cautiously to the stirred mixture. The resulting solid was extracted into diethyl ether (3 x 300 ml). The organic solution was dried over magnesium sulfate, filtered and evaporated to leave a solid. This solid was stirred in isohexane : ethyl acetate mixture (100:1, 300 ml) for 16 hours. The resulting solid was filtered and dried to give the subtitle compound as an off white solid (60 g). Mpt 90-92 ⁰C NMR δcDcis: 7.42 (dd, IH), 7.01 (t, IH), 4.88 (d, 2H), 2.04 (t, IH).

References:

WO2006/62477,2006,A1 Location in patent:Page/Page column 4