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 N-Boc-D-proline
37784-17-1

N-Boc-D-proline synthesis

5synthesis methods
Di-tert-butyl dicarbonate

24424-99-5

D-Proline

344-25-2

N-Boc-D-proline

37784-17-1

Step-1: Synthesis of N-tert-butoxycarbonyl-(D)-proline: To a stirred solution of D-proline (100 g, 868.58 mmol) in dioxane (400 mL, 8 vol.) was added NaHCO3 (182.4 g, 2.5 equiv.) and water (800 mL, 8 vol.) and the reaction mixture was stirred for about 30 min at room temperature. The reaction mixture was cooled to 0-5 °C, di-tert-butyl dicarbonate (Boc2O) (224.26 g, 1.2 eq.) was slowly added and stirring was continued at 0-5 °C for 1 hour. Subsequently, the reaction mixture was gradually warmed to room temperature and stirred overnight (12-16 h). The progress of the reaction was monitored by thin layer chromatography (TLC). After completion of the reaction, the dioxane solvent was removed by evaporation under reduced pressure. The aqueous layer was acidified to pH 2-3 with 4N HCl solution at 0-5 °C. The aqueous layer was extracted with ethyl acetate (4 x 200 mL), the organic layers were combined, washed with water and dried with anhydrous Na2SO4. The organic layer was concentrated under reduced pressure to give a white solid product. The white solid was added to heptane (200 mL) and stirred at room temperature for 2 hours. The solid was collected by filtration and dried under vacuum at 45-50 °C to give the target compound (wt: 125 g, yield: 90-95%).1H NMR (300 MHz, CDCl3): δ 9.20 (br, 1H), 4.34 (t, 1H), 3.54-3.13 (m, 2H), 2.31-2.25 (m, 1H), 2.09- 1.88 (m, 3H), 1.48-1.42 (b, 9H); MS: [M + Na]+ 238 (100%).

N-Boc-D-proline Related Search:

霍邱县| 左贡县| 芒康县| 盱眙县| 宁津县| 舟山市| 临夏县| 沙河市| 唐河县| 涟水县| 万宁市| 特克斯县| 惠水县| 朝阳区| 益阳市| 连州市| 油尖旺区| 南江县| 礼泉县| 鱼台县| 黄龙县| 顺平县| 图片| 正定县| 府谷县| 龙川县| 长乐市| 布拖县| 平阳县| 宁波市| 搜索| 疏附县| 神木县| 长乐市| 阿克陶县| 富裕县| 汶川县| 稻城县| 阿荣旗| 扎兰屯市| 黔江区|