Iodoethane → 4-Ethyl-3-fluoropyridine

To a stirred solution of LDA (200 mmol) in dry THF (400 ml) (prepared by a similar method to that used in Example 1) at -70° C. and under a nitrogen atmosphere was added dropwise 3-fluoropyridine (20 g, 200 mmol). After 30 minutes at this temperature ethyl iodide (60 g, 370 mmol) was added dropwise to the reaction and the mixture was allowed to warm slowly to between -10° and -5° C. whereupon an exotherm occurred and the temperature rose to 15° to 20° C. The mixture was stirred for a further 30 minutes after which time the reaction was quenched by the addition of water (50 ml) and the organic phase separated. The aqueous phase was extracted with ether (3×50 ml) and the combined organic layers were dried over magnesium sulphate and concentrated under reduced pressure. The resulting liquid was distilled at atmospheric pressure to yield the title compound (13 g), b.p. 154°-158° C., which was characterised by 1H-NMR spectroscopy.

1. customat -70° C.
2. temperatureto warm slowly to between -10° and -5° C. whereupon an exotherm
3. customrose to 15° to 20° C
4. customwas quenched by the addition of water (50 ml)
5. customthe organic phase separated
6. extractionThe aqueous phase was extracted with ether (3×50 ml)
7. dry with materialthe combined organic layers were dried over magnesium sulphate
8. concentrationconcentrated under reduced pressure
9. distillationThe resulting liquid was distilled at atmospheric pressure

ORD record

ord-e3a3accfe39849709c7a7d2adf7302ee

Source dataset

uspto-grants-1994_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05278175