Dimethyl Sulfoxide → 3-(Pyridin-2-YL)propanal

Dimethyl sulphoxide (3.3 ml) was added dropwise to a solution of oxalyl chloride (3.9 ml) in dichloromethane (25 ml) at -78° under nitrogen. After gas evolution had ceased (5 min) a solution of 2-pyridinepropanol (4.0 g) in dichloromethane (20 ml) was added over 5 min and the solution stirred at -78° for 20 min. Triethylamine (5 ml) was added dropwise to the solution, then the resulting dark green mixture warmed to 20° and washed with 2M sodium carbonate solution (20 ml). The organic phase was dried and evaporated in vacuo to give 2-pyridinepropanal. This aldehyde was immediately dissolved in THF (30 ml) and added dropwise to a 3M solution of methylmagnesium chloride in THF (20 ml) at 0°-5° under nitrogen. After 1 h, water (10 ml) was cautiously added followed by sufficient 2M hydrochloric acid to dissolved all the magnesium residues (resulting pH~7 ). The solution was extracted with dichloromethane (3×30 ml) and the organic extracts dried and evaporated in vacuo to a dark oil. Kugelrohr bulb to bulb distillation (b.p. 130°-135°/0.7 mm) afforded the title compound as a pale yellow oil (0.91 g), t.l.c. ethyl acetate Rf 0.17.

1. custom(5 min)
2. additionwas added over 5 min
3. temperaturethe resulting dark green mixture warmed to 20°
4. washwashed with 2M sodium carbonate solution (20 ml)
5. customThe organic phase was dried
6. customevaporated in vacuo

ORD record

ord-4945949323a34d77928f092ea109559c

Source dataset

uspto-grants-1991_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04996218