Reaction #661301

Reaction equation

Copper(I) cyanide

2,5-dibromo-3-methylpyridine

2,5-Dibromo-3-methylpyridine

water

→

50

Yield 74.0%

5-Bromo-3-methylpicolinonitrile

Yield 74.0%

Solvents

DMF

Conditions

Workup

1. 1
   Temperaturethe mixture was heated
2. 2
   Temperatureat reflux for 2 h
3. 3
   Extractionthe products were extracted with ethyl acetate (3×300 mL)
4. 4
   WashThe combined extracts were washed with water (3×300 mL), brine (300 mL)
5. 5
   Dryingdried with sodium sulfate
6. 6
   Otherevaporated to dryness
7. 7
   Washeluting with chloroform

Procedure

Copper(I) cyanide (21 g, 0.24 mol) was added to a solution of 2,5-dibromo-3-methylpyridine (49, 60 g, 0.24 mol) in dry DMF (200 mL), and the mixture was heated at reflux for 2 h. After cooling to room temperature, water (1500 mL) was added to the mixture and the products were extracted with ethyl acetate (3×300 mL). The combined extracts were washed with water (3×300 mL), brine (300 mL), dried with sodium sulfate and evaporated to dryness. The brown oily residue was subjected to flash column chromatography (silica gel), eluting with chloroform, to yield 50 as a white solid (35 g, 74%): mp 86-88° C. 1H NMR (300 MHz, CDCl3) δ 8.55 (d, J=1.8 Hz, 1H), 7.84 (d, J=1.5 Hz, 1H), 2.53 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 149.75, 140.68, 139.95, 132.25, 124.61, 115.90, 18.59; EIMS m/z 196/198 (M+); CIMS 197/199 (MH+). The 1H NMR spectrum is consistent with previously published data (Bioorg. Med. Chem. 1999, 7, 1845-1855).

Source