一二三四区视频,亚洲少妇熟女色,日本久热无码视频网,欧美国产日韩大尺度,亚洲a视频,久久少妇一区二区,日韩999无码视频,刺激久久久久久久,啊啊啊啊不要啊在线

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
010-86108875
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List 4-Chloro-3-hydroxybenzoic acid
34113-69-4

4-Chloro-3-hydroxybenzoic acid synthesis

4synthesis methods
Benzoic acid, 4-chloro-3-methoxy-, 2-propen-1-yl ester

931409-94-8

4-Chloro-3-hydroxybenzoic acid

34113-69-4

General procedure for the synthesis of 4-chloro-3-hydroxybenzoic acid from compound (CAS: 931409-94-8): boron tribromide (1 M in dichloromethane, 31 mL, 31.504 mmol) was slowly added dropwise to a solution of compound 38 (3.56 g, 15.752 mmol) in dichloromethane (30 mL) under ice bath cooling conditions. The reaction mixture was stirred at 0°C to room temperature for 18 hours. Upon completion of the reaction, the reaction was quenched with 0.88 aqueous ammonia solution and stirring was continued for 90 minutes at room temperature. Subsequently, the reaction mixture was acidified to pH 1 by dropwise addition of 2N aqueous hydrochloric acid solution and then extracted with ether (2 x 50 mL). The organic layers were combined, dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford 4-chloro-3-hydroxybenzoic acid as a light yellow solid in 90% yield (2.45 g). The product was characterized by 1H NMR (400 MHz, CD3OD): δ 7.36-7.38 (d, 1H), 7.44-7.47 (dd, 1H), 7.54-7.55 (d, 1H); LRMS APCI m/z 171 [M-H]-.

-

Yield: 90%

Reaction Conditions:

Stage #1:3-methoxy-4-chlorobenzoic acid allyl ester with boron tribromide in dichloromethane at 0 - 20; for 18 h;
Stage #2: with ammonia in dichloromethane;water at 20; for 1.5 h;
Stage #3: with hydrogenchloride in dichloromethane;water; pH=1

Steps:

39
Boron tribromide (1M in dichloromethane, 31 mL, 31.504mmol) was added to an ice-cooled solution of the product of preparation 38 (3.56g, 15.752mmol) in dichloromethane (3OmL) and the mixture was stirred at O0C to room temperature for 18 hours. The reaction was quenched with 0.88 ammonia solution and stirred at room temperature for 90 minutes. The reaction mixture was acidified to pH 1 by dropwise addition of 2N hydrochloric acid (aq) and extracted with diethyl ether (2x50mL). The combined organic layers were dried over sodium sulfate and concentrated in vacuo to afford the title compound as a pale yellow solid in 90% yield, 2.45g. 1HNMR(400MHz, CD3OD) δ: 7.36-7.38(d, 1H), 7.44-7.47(dd, 1H), 7.54-7.55(d, 1H); LRMS APCI m/z 171 [M-H]-

References:

Location in patent:Page/Page column 53

4-Chloro-3-hydroxybenzoic acid Related Search:

济南市| 太康县| 沂水县| 胶州市| 上林县| 古浪县| 达拉特旗| 同德县| 张家口市| 延安市| 裕民县| 汉阴县| 太湖县| 金湖县| 新津县| 进贤县| 裕民县| 固镇县| 大姚县| 宁波市| 邵阳县| 盐山县| 砚山县| 乌兰浩特市| 临湘市| 丹巴县| 台湾省| 达拉特旗| 光泽县| 黄石市| 雅安市| 左贡县| 永济市| 明水县| 清丰县| 易门县| 互助| 白玉县| 博爱县| 巴东县| 灌南县|