preparation method of 6-bromomethyl-2-pyridinemethanol_industrial additives

background and overview^[1][2]

6-bromomethyl-2-pyridylmethanol is an alcohol derivative that can be used as an organic intermediate and can be obtained by bromination of 2,6-pyridylmethanol.

preparation method^[1-2]

method 1: 2-bromomethyl-6-pyridinemethanol. reflux 2,6-pyridylmethanol (15 g, 108 mmol) in hbr (48% aqueous solution) for 1 h. after cooling to 0 °c, carefully add ice-cold saturated naoh solution until ph = 14 is reached. the product was immediately extracted with 4 × 100 ml ch₂cl₂, and the combined organic layers were dried with mgso₄. all volatiles were removed in vacuo to give a slightly pinkish crude product. pure 1-bromomethyl-6-pyridinemethanol was obtained by recrystallization from hexane/ethyl acetate (5:1). yield: 6.26g (28.7%), white microcrystalline solid. 2-bromomethyl-6-pyridinemethanol. yield¹h nmr (cdcl₃, 250mhz, 25℃): δ3.93 (s, br, 1h, oh), 4.54 (s, 2h, ch2br), 4.76 (s, 2h, ch2oh), 7.10 (d 1 h, 3 jhh = 7.7hz, aryl-h 5), 7.34 (d, 1h, 3hhh = 7.6hz, aryl phthalocyanine pigment base-h3), 7.69 (t, 1h, 3hhh = 7.7hz, aryl-h4). ¹³c {1h} nmr (cdcl₃, 63mhz, 25℃): δ33.44 (ch2br), 63.98 (ch2oh), 119.89 (aryl-c3), 122.09 (aryl-c5), 137.76 (aryl-c4), 155.72 (aryl-c2), 159.21 (aryl-c6).

method 2: add pph₃ (s.24g, 20mmol) and nbs (3.56g, 20mmol) to the 2,6-pyridine dimethanol (4.17g, 30mmol) solution. the resulting solution was stirred at room temperature for 1 hour. the solvent was evaporated and the residue was purified by flash chromatography on a silica gel column. elution with 2:1 hexane-etoac gave the product 6-bromomethyl-2-pyridinemethanol, which was further purified by recrystallization from 1:5 chcl₃-hexane. yield 1.61 g (40%).

main reference materials

[1] organometallics 2008, 27, 8, 1892-1901

[2] u.s., 6329523, 11 dec 2001