成人免费xx,国产又黄又湿又刺激不卡网站,成人性视频app菠萝网站,色天天天天

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
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 Ethyl 2-bromoisobutyrate
600-00-0

Ethyl 2-bromoisobutyrate synthesis

6synthesis methods
-

Yield:600-00-0 92.53%

Reaction Conditions:

Stage #1: 2-bromo-2-methylpropionic acidwith zinc for 0.5 h;
Stage #2: with hydrogen bromide for 0.5 h;
Stage #3: ethanol at 95;

Steps:

1; 2; 3 Example 3

Transfer the filtrate to a 500 ml three-necked flask with a thermometer and a stirring paddle.A three-necked flask was fixed to the bottom of the distillation column.Add zinc powder to the three-necked flask: 0.9g, stir for 30 minutes, the color of the material in the three-necked bottle will gradually fade.40% hydrobromic acid was added to the three-necked flask: 1.2 g, stirred for 30 minutes, and then ethanol was added to 33.1 g.(content: 99.0%, 0.7124 mol).The outer wall of the three-necked flask was heated in a water bath, and the water temperature of the water bath was set to 95 °C. Open stirring, warm up the total reflux reaction, reverseThe turbid light component with higher water content is intermittently produced during the process. After 5 to 10 hours of reflux dehydration reaction, sample detectionThe content of the material in the reaction flask is stopped when the content of α-bromoisobutyric acid is less than 3.5%.The outer wall of the reaction bottle is cooled with 20-30 ° C cooling water. When the internal temperature is less than 35 ° C, stirring is stopped and the reaction bottle is placed.The material was transferred to a separatory funnel and the reaction was washed three times with 200 ml of deionized water. After washing, it will be in the separatory funnelThe material was transferred to a 500 ml three-necked flask with a thermometer and a stirring paddle. Three-necked flask was fixed to the recovery unit, three-necked flaskThe outer wall is heated in a water bath, the water temperature of the water bath is set to 80 ° C, and the internal temperature of the reaction bottle is controlled to be ≤ 60 ° C, and the vacuum degree is ≥ 0.06 MPa.The n-hexane was recovered under reduced pressure. After the recovery, 73.4 g of a colorless transparent ethyl α-bromoisobutyrate was obtained (content: 96.8%, yield:92.53%).

References:

CN108997107,2018,A Location in patent:Paragraph 0043; 0047-0049; 0050; 0054-0057; 0061-0063

Ethyl 2-bromoisobutyrate Related Search: