반응 #215488

반응 방정식

2-propynyl bromide

potassium carbonate

4-(2,3-dimethyl-5-benzofuranyl)-piperidine

→

1-(2-propynyl)-4-(2,3-dimethyl-5-benzofuranyl)-piperidine

용매

acetone

acetone

반응 조건

후처리

1. 1
   온도The reaction mixture is heated to 40° for 4 hours
2. 2
   여과the inorganic salts are filtered off
3. 3
   기타The filtrate is evaporated in a rotary evaporator
4. 4
   workup.ADDITIONa main spot at an Rf value of about 0.7, in addition to 4 secondary spots
5. 5
   기타The resulting oil is chromatographed on 50 g of silica gel
6. 6
   세척eluting agent

실험 절차

4.15 g (0.030 mol) of anhydrous potassium carbonate are added to a solution of 2.29 g (0.010 mol) of 4-(2,3-dimethyl-5-benzofuranyl)-piperidine (c.f. Example 1) in 25 ml of acetone, and a solution of 1.3 g (0.011 mol) of 2-propynyl bromide in 11 ml of acetone is added dropwise in the course of 10 minutes, with stirring. The reaction mixture is heated to 40° for 4 hours and then cooled to room temperature and the inorganic salts are filtered off. The filtrate is evaporated in a rotary evaporator. The brown oil which remains has, in the thin layer chromatogram (silica gel/5% methanol/chloroform), a main spot at an Rf value of about 0.7, in addition to 4 secondary spots. The resulting oil is chromatographed on 50 g of silica gel using chloroform as the solvent and eluting agent, whereupon 1-(2-propynyl)-4-(2,3-dimethyl-5-benzofuranyl)-piperidine is obtained, as the main fraction, as a yellowish oil with an Rf value of about 0.7. This base is dissolved in about 3 ml of methanol and converted into the hydrochloride by acidifcation with hydrogen chloride solution and the hydrochloride is made to crystallise by adding about 20 ml of ether and is filtered off with suction. The hydrochloride thus obtained as white crystals melts at 224°-225°.

출처