午夜插插,噜噜噜影院,啪啪伊人网,欧美熟夫,景甜吻戏视频,男人强操性感蕾丝美女视频在线网站,日本美女跳舞视频

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 2-Chloro-5-hydroxypyrimidine
4983-28-2

2-Chloro-5-hydroxypyrimidine synthesis

4synthesis methods
2-Chloro-5-methoxypyrimidine (0.46 g, 3.18 mmol) in methylene chloride (10 mL) was treated with 1.0 N boron tribromide (16 mL, 16 mmol) at room temperature. The solution was stirred overnight. After that, the reaction was partitioned between saturated NaHCO3 and DCM. The aqueous layer was extracted with additional DCM. Combined the organic layers and dried (MgSO4), filtered, and concentrated to obtain the crude product. The residue was purified by flash column chromatography on silica gel to give 2-Chloro-5-hydroxypyrimidine.2-Chloro-5-hydroxypyrimidine

-

Yield:4983-28-2 91%

Reaction Conditions:

with hydrogen bromide;DL-methionine in acetic acid; for 5 h;Reflux;

Steps:

1-4 Example 3

Prepare 1L four-necked flask with a stirring device and thermometer.Add 100 g of 2-chloro-5-methoxypyrimidine,300 mL of acetic acid was added to the reaction flask,Stir well, then add 153g of 48% hydrobromic acid and 1g of methionine.Warming up to reflux reaction for 5 h,Sampling HPLC controlled until the end of the reaction, product content 96%, dihydroxy by-product 0.5%;After dropping to room temperature, 300 mL of water was added to the reaction solution, and the mixture was extracted three times with 300 mL of dichloromethane.The organic phases were combined and washed with saturated sodium bicarbonate solution.Then, it is dried over anhydrous sodium sulfate, and after filtration, the organic phase is concentrated under reduced pressure to give a crude product;The crude product was recrystallized from the crude product to give a pale yellow solid, 82 g.The yield was 91% and the purity was 98%.

References:

CN110041269,2019,A Location in patent:Paragraph 0006; 0012-0015

2-Chloro-5-hydroxypyrimidine Related Search: