Reacción #600259

Ecuación de reacción

(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

Rendimiento 74.0%

Disolventes

toluene

water

Condiciones de reacción

Tratamiento posterior

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

Procedimiento

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).

Fuente