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 3-Bromo-2,5-difluorobenzaldehyde
112279-64-8

3-Bromo-2,5-difluorobenzaldehyde synthesis

2synthesis methods
-

Yield:-

Reaction Conditions:

with water;hypophosphorous acid;acetic acid;sodium nitrite at 0 - 20; for 1 h;

Steps:

19.4
4.6 g of 4-amino-3-bromo-2,5-difluorobenzaldehyde, 110 ml_ glacial acetic acid, and 54 ml_ of hypophosphorous acid were placed under nitrogen in an oven-dried flask and chilled to 00C. 1.96 g of sodium nitrite dissolved with 11 ml_ water was added to the reaction mixture from an addition funnel maintaining reaction temperature below 15°C. The mixture was warmed to room temperature and stirred for 1 hour, diluted into 300 ml_ of ice water and extracted 3 times with methylene chloride. The combined organic layers were extracted with water, 2 times with 10% sodium hydroxide, 2 times with water, dried over sodium sulfate, filtered, concentrated, and purified by flash chromatography on silica. The product fractions were concentrated and dried under vacuum to give 2.79 g of product. GCMS (M)222; 1 H NMR (400 MHz, DMSO-c/6) δ ppm 7.66 (ddd, J=8.06, 4.83, 3.22 Hz, 1 H) 8.12 (ddd, J=7.52, 5.37, 3.22 Hz, 1 H) 10.13 (d, J=2.42 Hz, 1 H).

References:

PFIZER INC. WO2009/69044, 2009, A1 Location in patent:Page/Page column 91-92

3-Bromo-2,5-difluorobenzaldehyde Related Search:

鄂托克旗| 兴国县| 通山县| 长寿区| 重庆市| 屯昌县| 镇原县| 南召县| 阜城县| 彰化县| 上蔡县| 松溪县| 东至县| 凤台县| 望都县| 浮山县| 株洲市| 乌兰察布市| 长治县| 绥宁县| 黎城县| 自治县| 老河口市| 大连市| 南宫市| 墨江| 紫金县| 彭州市| 凌云县| 武城县| 吴忠市| 北票市| 龙泉市| 闽侯县| 旬阳县| 广宁县| 呈贡县| 普安县| 思南县| 邮箱| 大安市|