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 5-CHLORO-2-(CHLOROMETHYL)PYRIDINE
10177-24-9

5-CHLORO-2-(CHLOROMETHYL)PYRIDINE synthesis

7synthesis methods
-

Yield: 89%

Reaction Conditions:

with thionyl chloride;N,N-dimethyl-formamide in dichloromethane at 0 - 20; for 4 h;

Steps:


5-chloro-2(chloromethyl)pyridine; [00372] To a 0 °C solution of 5-chloropicolinic acid (3.00 g, 19.0 mmol) indichloromethane (20 mL) was added sulfurous dichloride (2.78 mL, 38.1 mmol), after which the reaction was warmed to room temperature and stirred at that temperature for 4 hours. The reaction was then concentrated to dryness, then reconstituted in dichloromethane (5 mL). Methanol (10 mL) was added to the reaction mixture, and the reaction was allowed to stir at room temperature for 12 hours, after which it was then diluted with water, extracted with ethyl acetate (3 x 50 mL), washed with water, then washed with saturated sodium bicarbonate solution, dried (magnesium sulfate), filtered and concentrated. Purification was achieved by silica gel chromatography (ISCO 80g) using 0 to 80% ethyl acetate in hexanes to afford methyl 5-chloropicolinate was as an off-white solid (2.75 g, 15.2 mmol, 80% yield ).[00373] To a 0 °C solution of methyl 5-chloropicolinate (2.70 g, 15.7 mmol) in methanol (50 mL) was added sodium borohydride (1.79 g, 47.2 mmol), after which the reaction was warmed to room temperature and stirred at that temperature for 4 hours. The reaction mixture was then concentrated to a residue which was treated with 1M hydrochloric acid solution (15 mL), extracted with ethyl acetate (3 x 100 mL), washed with water, then washed with saturated sodium bicarbonate solution, dried (magnesium sulfate), filtered and concentrated. Purification was achieved by silica gel chromatography (ISCO 80g) using 0 to 60% ethyl acetate in hexanes to afford (5-chloropyridin-2-yl)methanol was as an off-white solid (2.15 g, 14.9 mmol, 95% yield).[00374] To a 0 °C solution of (5-chloropyridin-2-yl)methanol (2.10 g, 14.6 mmol) in dichloromethane (10 mL) was added sulfurous dichloride (1.60 mL, 21.9 mmol) followed by N,N-dimethylformamide (50 μ), after which the reaction was warmed to room temperature and stirred at that temperature for 4 hours. The reaction mixture was then concentrated to a residue which was reconstituted in water (15 mL), ethyl acetate (15 mL), and saturated sodium bicarbonate solution (15 mL). The organic layers were separated and washed with saturated sodium chloride solution, dried (magnesium sulfate), filtered and concentrated. Purification was achieved by silica gel chromatography (ISCO 40g) using 0 to 50% ethyl acetate in hexanes to afford 5-chloro-2(chloromethyl)pyridine as an light brown oil (2.11 g, 13.0 mmol, 89% yield).

References:

IRONWOOD PHARMACEUTICALS, INC.;HUDSON, Colleen;BARDEN, Timothy, C.;JIA, James;MERMERIAN, Ara;PENG, Bo;YANG, Jane;YU, Xiang, Y.;SPROTT, Kevin WO2012/88469, 2012, A1 Location in patent:Page/Page column 152-153

5-CHLORO-2-(CHLOROMETHYL)PYRIDINE Related Search:

县级市| 新和县| 延寿县| 新乡市| 通山县| 彭水| 潢川县| 温泉县| 建平县| 昌平区| 宝应县| 枝江市| 双牌县| 江安县| 五河县| 庆元县| 延寿县| 盈江县| 沐川县| 梁山县| 临湘市| 桦南县| 乌鲁木齐县| 淅川县| 南宁市| 洪雅县| 福清市| 汽车| 花莲县| 沽源县| 揭阳市| 阳西县| 长葛市| 漳浦县| 改则县| 九江市| 绩溪县| 元谋县| 磴口县| 肥城市| 石渠县|