Reaktion #7304

Reaktionsgleichung

dimethyl carbonate

4-Methyl-pyridin-3-ylamine

potassium t-butoxide

THF

→

(4-Methyl-pyridin-3-yl)-carbamic acid methyl ester

Ausbeute 89.0%

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat 0° C
2. 2
   Sonstigestayed below 0° C
3. 3
   Sonstigethe red slurry was quenched with 50 ml water (25 volumes)
4. 4
   Extraktionextracted in 50 ml ethyl acetate (25 volumes)
5. 5
   ExtraktionThe aqueous layer was extracted with 50 ml ethyl acetate (25 volumes)
6. 6
   Einengenthe orange organic layers were concentrated to an orange solid
7. 7
   Einengenconcentrated to dryness
8. 8
   Sonstigeto give very clean light orange solids

Vorschrift

The synthesis was carried out by charging 2 grams (1 equiv., 18.5 mmol) 4-Methyl-pyridin-3-ylamine to a solution of 6.55 grams potassium t-butoxide (3 equiv., 55.5 mmol) in 10 ml THF (6.66 euiv., 123 mmol) at 0° C. Upon anion formation, 2.34 ml dimethyl carbonate (1.5 equiv., 27.7 mmol) were charged to the reaction at a rate so that the temperature stayed below 0° C. The reaction was complete within 30 minutes and the red slurry was quenched with 50 ml water (25 volumes) and extracted in 50 ml ethyl acetate (25 volumes). The aqueous layer was extracted with 50 ml ethyl acetate (25 volumes) and then the orange organic layers were concentrated to an orange solid. NMR data showed that t-butanol existed in the product so the solids were slurried in 10 ml toluene (5 volumes) and then concentrated to dryness. This operation was performed three times in order to give very clean light orange solids. (89% yield). 1H NMR: δ8.90 (1 H, brs), 8.28 (1 H, d, J=4.8), 7.16-7.14 (1 H, m), 6.54 (1 H, brs), 3.80 (3 H, s), 2.29 (3 H, s).

Quelle