Sulfuric Acid → 4-(Dimethoxymethyl)pyridine

To a solution of 4-pyridinecarboxaldehyde (100.00 g, 0.93 mol) and trimethylorthoformate (159.20 g, 1.50 mol) in methanol (180 mL) at 0° C., under N2, was added concentrated sulfuric acid (41 mL, 0.45 mol). The resulting white suspension was heated to reflux and stirred for 24 hours. The reaction solution became clear after 2 h. After cooling to room temperature, the reaction mixture was poured slowly into a solution of 25 wt. % sodium methoxide (360 mL) in methanol (300 mL). The mixture was then concentrated in vacuo to a light brown thick oil. To this crude oil was added t-butylmethyl ether (500 mL), followed by the slow addition of water (40 mL) (to convert the inorganics to filterable solids). After filtration through a pad of Celite, the filtrate was concentrated to yield a light brown oil. The crude oil was vacuum distilled to yield the desired product as a colorless oil

1. temperatureThe resulting white suspension was heated
2. temperatureto reflux
3. waitThe reaction solution became clear after 2 h
4. concentrationThe mixture was then concentrated in vacuo to a light brown thick oil
5. additionTo this crude oil was added t-butylmethyl ether (500 mL)
6. additionfollowed by the slow addition of water (40 mL) (
7. filtrationAfter filtration through a pad of Celite
8. concentrationthe filtrate was concentrated
9. customto yield a light brown oil
10. distillationdistilled

ORD record

ord-233255ddce054bac870bb7d35d162dd1

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07132544B2