2-(4-溴苯基)-3-羟基丙腈

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a mixture of 24 g (0.11 mol) 2-cyano-2-(4-bromophenyl)-ethanol and 4.5 g (0.055 mol) pyridine in 100 ml CH2Cl2 are slowly added, at -5° to 0°, 12 g (0.044 mol) PBr3. The mixture is stirred for 3 hours at room temperature, thereafter for 2 hours at 40°, allowed to cool off, then poured into 500 ml ice water and extracted with CH2Cl2. The extract is washed with water, dried and evaporated. The resulting residue is chromatographed over a silica gel column with hexane/diethylether 6:4. The glassy residue obtained after evaporation is worked up in toluene and thereafter ether to give the title compound in the form of a yellow powder, m.p. 171° (decomposing). are slowly added, at -5° to 0° for 2 hours at 40° to cool off extracted with CH2Cl2 The extract is washed with water dried evaporated The resulting residue is chromatographed over a silica gel column with hexane/diethylether 6:4 The glassy residue obtained after evaporation

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a mixture of 87 g (0.29 mol) 3-cyano-3-(4-bromophenyl)-2-ketopropionic acid ethyl ester, 44 ml 38% formaldehyde and 180 ml water are added dropwise within 1 hour and with stirring, at a temperature of 10°-15°, a solution of 26 g Na2CO3 in 85 ml water. The mixture is stirred further for 17 hours at room temperature and then three times extracted with 200 ml diethylether. The ether solution is washed with water, dried, evaporated and the residue kept for one hour at 60° under high vacuum. The oily residue (title compound) is chromatographed over a silica gel column with CH2Cl2 /CH3OH 97:3, Rf=0.4. are added dropwise within 1 hour The mixture is stirred further for 17 hours at room temperature three times extracted with 200 ml diethylether The ether solution is washed with water dried evaporated The oily residue (title compound) is chromatographed over a silica gel column with CH2Cl2 /CH3OH 97:3, Rf=0.4