(2,4,6-trichloropyridin-3-yl)Methanol synthesis

Yield:-

Reaction Conditions:

Stage #1: methyl 2,4,6-trichloronicotinatewith diisobutylaluminium hydride in tetrahydrofuran;toluene at -5 - 0;
Stage #2: with water in tetrahydrofuran;methanol;toluene at -20;

Steps:

17.B

To a stirred solution of 2,4,6-Trichloro-nicotinic acid methyl ester (1.826 g, 7.59 mmol) in THF (36 mL) was added dropwise DIBAL (1.5 M in toluene, 30.4 mL, 45.6 mmol) at - 5 °C. The reaction mixture was stirred for 30 min at 0 °C before it was cooled down to - 20 °C and MeOH (30 ml) and water (30 mL) were added subsequently. The solvents were removed in vacuo, the residue was partitioned between water and EA and extracted with EA (3x 30 mL). The organic layer was dried over Na₂SO₄, filtered, and concentrated in vacuo to give the title compound which was used in the next step without further purification.

References:

WO2010/31589,2010,A1 Location in patent:Page/Page column 41