Reaktion #600259

Reaktionsgleichung

(6-chloro-4-iodo-pyridin-3-yl)-carbamic acid tert-butyl ester

1-butyne

triethylamine

→

tert-butyl 4-(but-1-ynyl)-6-chloropyridin-3-ylcarbamate

Ausbeute 74.0%

Lösungsmittel

toluene

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe solid was filtered off
2. 2
   Waschenwashed with ethyl acetate (60 mL×3)
3. 3
   SonstigeThe filtrate was evaporated under reduced pressure
4. 4
   Sonstigethe residue was purified by column chromatography on silica gel (petroleum ether/ethyl acetate, 10/1)

Vorschrift

To a deoxygenated solution of (6-chloro-4-iodo-pyridin-3-yl)-carbamic acid tert-butyl ester (6.0 g, 16.9 mmol), 1-butyne (9 g, 169 mmol), CuI (160.1 mg, 0.84 mmol) and triethylamine (3.4 g, 33.2 mmol) in toluene (40 mL) and water (14 mL) was added Pd(PPh3)2Cl2 (592 mg, 0.84 mmol) under N2 in a autoclave. The mixture was heated to 70° C. and stirred for 24 h. The solid was filtered off and washed with ethyl acetate (60 mL×3). The filtrate was evaporated under reduced pressure and the residue was purified by column chromatography on silica gel (petroleum ether/ethyl acetate, 10/1) to give tert-butyl 4-(but-1-ynyl)-6-chloropyridin-3-ylcarbamate (3.5 g, 74%). 1H-NMR (CDCl3, 300 MHz) δ 9.13 (s, 1H), 7.22 (s, 1H), 6.98 (s, 1H), 2.53 (q, J=7.5 Hz, 2H), 1.54 (s, 9H), 1.29 (t, J=7.5 Hz, 3H).

Quelle