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 Rabeprazole
117976-89-3

Rabeprazole synthesis

12synthesis methods
2,3-dimethyl-4-(3-methoxy-propoxy)pyridine

1080503-70-3
2 suppliers
inquiry

1H-Benzimidazole-2-sulfinic acid, (1R,2S,5R)-5-methyl-2-(1-methylethyl)cyclohexyl ester

1080503-68-9
0 suppliers
inquiry

-

Yield:117976-89-3 90%

Reaction Conditions:

Stage #1: 2,3-dimethyl-4-(3-methoxy-propoxy)pyridinewith n-butyllithium in tetrahydrofuran at -90 - -80;
Stage #2: (-)-menthyl 2-benzimidazolylsulphinate in tetrahydrofuran at -80 - -20;

Steps:

10

Example 10.- Preparation of rabeprazole, compound of general formula (11) wherein R2 is hydrogen, R4 is hydrogen, R5 is methyloxypropyloxy, and R6 is methyl; [Show Image] 4.26 g (21.8 mmol) of 2,3-dimethyl-4-(3-methoxy-propoxy)piridine were dissolved in 42 ml of anhydrous tetrahydrofuran at room temperature under inert atmosphere, and the solution was then cooled below - 90° C. 8.72 ml of a 2.5M solution of n-butyl lithium (21.8 mmol) were added dropwise and the temperature was maintained below -80° C. 2,3-dimethyl-4-(3-methoxy-propoxy)pyridine may be prepared in accordance with the process described in EP-A-0268956. After 30 minutes at this temperature, the mixture was slowly added to a solution of 2.0 g (6.24 mmol) of (-)-menthyl 2-benzimidazolylsulphinate, as obtained in Example 7, in 36 ml of tetrahydrofuran cooled below -80°C as well. Once the addition was completed, the resulting mixture was allowed to stand up to -20° C, then 100 ml of water were slowly added and it was allowed to reach room temperature. The reaction mixture was analyzed by HPLC, and conversion and yield were found to be 95% and 90% respectively.

References:

EP1992619,2008,A1 Location in patent:Page/Page column 16

Rabeprazole Related Search: