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 1,2,4,5-TETRABROMOBENZENE
636-28-2

1,2,4,5-TETRABROMOBENZENE synthesis

13synthesis methods
-

Yield:636-28-2 98 %

Reaction Conditions:

Stage #1: 2,3,5,6-tetrabromoanilinewith sulfuric acid in water;
Stage #2: with sodium nitrite in water at 0;

Steps:

21 Example 21: 4,6-bis(2,4,6-triisopropylphenyl)-1,3-bis(dicyclohexylphosphino)-benzene

Add 2,3,5,6-tetrabromoaniline (4.09 g, 10.0 mmol) into a 250 mL two-neck flask, add 5.4 mL concentrated sulfuric acid (dissolved in 30 mL water), and stir for 12 h. Cool to 0°C, add sodium nitrite (1.5 g, 22.0 mmol) dissolved in 10 mL of water, and react for 4 h.Extracted three times with dichloromethane (300 mL), the organic phase was washed with 80 mL saturated sodium chloride solution, and the aqueous phase was extracted three times with dichloromethane (50 mL).The combined organic phases were dried over Na2SO4 and concentrated under reduced pressure. The residue was separated and purified by silica gel column chromatography (petroleum ether: ethyl acetate = 50:1) to obtain 3.86 g of the product with a yield of 98%.

References:

CN115385956,2022,A Location in patent:Paragraph 0096

1,2,4,5-TETRABROMOBENZENE Related Search:

天镇县| 深水埗区| 绥滨县| 宜丰县| 大悟县| 枣阳市| 颍上县| 瑞昌市| 临西县| 望城县| 黄骅市| 刚察县| 同江市| 河间市| 施甸县| 永寿县| 洛扎县| 澄江县| 腾冲县| 永顺县| 威海市| 固始县| 凤台县| 元朗区| 武定县| 满洲里市| 盐池县| 阳山县| 莱西市| 潮安县| 芷江| 大足县| 凤冈县| 砀山县| 新余市| 伊川县| 灌南县| 方城县| 安陆市| 苏尼特右旗| 平顺县|