Methyl iodide → 2-Methoxy-3-methyl-5-(trifluoromethyl)pyridine

Temperature

20 °C

A solution of 5.12 g (0.020 mol) of 3-bromo-2-methoxy-5-(trifluoromethyl)pyridine in 60 ml of ether was cooled to -70° C. and blanketed with nitrogen. A solution containing 0.021 mole of butyl lithium (8.4 ml of 2.5 M) was added slowly with stirring keeping the temperature below about -65° C. and the mixture allowed to react for another 30 min. Methyl iodide (0.62 ml, 0.01 mol) was added to the mixture and stirring continued at -70° C. for about 30 min. The mixture was allowed to warm to about 20° C. and was then poured onto a mixture of ice and saturated aqueous ammonium chloride. The organic layer that formed was recovered. The aqueous layer was extracted with ether and the extract added to the organic layer. The combined organic materials were dried over sodium sulfate and concentrated by evaporation under reduced pressure. The residue was distilled to obtain 2.1 g (54 percent of theory) of the title compound as a colorless oil boiling at 67°-69° C. at 24 mm pressure. The proton nmr spectrum was consistent with the assigned structure.

1. additionwas added slowly
2. customthe temperature below about -65° C.
3. customto react for another 30 min
4. stirringstirring
5. customThe organic layer that formed
6. customwas recovered
7. extractionThe aqueous layer was extracted with ether
8. additionthe extract added to the organic layer
9. dry with materialThe combined organic materials were dried over sodium sulfate
10. concentrationconcentrated by evaporation under reduced pressure
11. distillationThe residue was distilled

ORD record

ord-7a018f1b02f94af1a977bcc8af2baaeb

Source dataset

uspto-grants-1990_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04931452