天堂网亚洲,天天操天天搞,91视频高清,菠萝蜜视频在线观看入口,美女视频性感美女视频,95丝袜美女视频国产,超高清美女视频图片

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 Trolox
53188-07-1

Trolox synthesis

2synthesis methods
-

Yield:53188-07-1 99.3%

Reaction Conditions:

Stage #1: methyl 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylatewith sodium hydroxide;water in methanol at 80; for 2 h;
Stage #2: with potassium hydrogensulfate in methanol;water at 80; for 2 h;

Steps:

7 6-Hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic acid

Example 7 6-Hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic acid Into a 2000-L reactor provided with glass lining, methyl 6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylate (137.3 kg) obtained in Example 6 was placed and dissolved in methanol (137.3 kg). A solution containing water (411 kg) and sodium hydroxide (27 kg) was added dropwise thereto over two hours, whereby hydrolysis was performed at 80°C for two hours. The hydrolyzed mixture was neutralized with a solution of potassium hydrogensulfate (91.9 kg) dissolved in water (411.9 kg) at 80°C for two hours. The reaction mixture was centrifuged, and the obtained crystals were dried by means of a conical drier, to thereby yield 6-hydroxy-2,5,7,8-tetramethyl-chroman-2-carboxylic acid (130.2 kg) in the form of white powder. Reaction scores on the basis of hydroxy-2,3,5-trimethylbenzene and chemical purity which was determined through high-performance liquid chromatography (HPLC) were found to be as follows: Percent conversion: 99.9% Isolation yield: 99.3% Chemical purity: 99.6%

References:

EP1710239,2006,A1 Location in patent:Page/Page column 9

Trolox Related Search: