2,3-Dimethyl 2,3-pyridinedicarboxylate → (Pyridine-2,3-diyl)dimethanol--hydrogen chloride (1/1)

Temperatur

5 °C

To a solution of pyridine-2,3-dicarboxylic acid dimethyl ester (25.0 g, 128.1 mmol) in ethanol (183 mL) was added sodium borohydride (24.2 g, 640.5 mmol). The resulting mixture was cooled to 5° C. while stirring under argon. A solution of calcium chloride (12.6 g, 113.5 mmol) in ethanol (77 mL) was added dropwise while maintaining a temperature between 10° C. and 15° C. After addition, the resulting mixture was allowed to warm to room temperature over 16 h. A mixture of 4:1 water/ethanol (100 mL) added and the resulting mixture stirred 1 hr, then evaporated in vacuo to yield a white solid, which was finely ground with mortar and pestle. The fine powder was refluxed for 3 h in ethanol (450 mL), cooled to room temperature and filtered through dicalite. The filtrate was filtered through Nylon 66, 0.45-μ filter, then treated with anhydrous hydrogen chloride gas until solution was pH 2 while cooling on ice bath. A white precipitate was isolated and washed with ethyl ether and dried to yield (2-hydroxymethyl-pyridin-3-yl)-methanol hydrogen chloride as a white solid. C7H9NO2; MS (ESI) m/z 140.1 (MH)+.

1. temperaturewhile maintaining a temperature between 10° C. and 15° C
2. additionAfter addition
3. temperatureto warm to room temperature over 16 h
4. additionadded
5. stirringthe resulting mixture stirred 1 hr
6. customevaporated in vacuo
7. customto yield a white solid, which
8. temperaturecooled to room temperature
9. filtrationfiltered through dicalite
10. filtrationThe filtrate was filtered through Nylon 66, 0.45-μ filter
11. additiontreated with anhydrous hydrogen chloride gas until solution
12. temperaturewhile cooling on ice bath
13. customA white precipitate was isolated
14. washwashed with ethyl ether
15. customdried

ORD-Eintrag

ord-964d4ce26f674defa31a85a47a61c06d

Quelldatensatz

uspto-grants-2014_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08673890B2