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 2-METHYLPYRAZOLO[1,5-A]QUINAZOLIN-5(4H)-ONE
25468-50-2

2-METHYLPYRAZOLO[1,5-A]QUINAZOLIN-5(4H)-ONE synthesis

3synthesis methods
-

Yield:25468-50-2 75%

Reaction Conditions:

with copper(l) iodide;caesium carbonate in water at 100; for 6 h;Inert atmosphere;chemoselective reaction;

Steps:

(I) Typical procedure for the preparation of pyrazolo[1,5-a]quinazolin-5(4H)-one (3a)

General procedure: To a solution of Cs2CO3 (2 mmol) in H2O (5 mL) were added methyl 2-bromobenzoate (1a, 1 mmol), 1H-pyrazol-5-amine (2a, 1.2 mmol), and CuI (0.2 mmol). The mixture was stirred at 100 °C under nitrogen atomasphere until a complete conversion as indicated by TLC. It was cooled to room temperature and then extracted with ethyl acetate. The combined organic phase was dried over anhydrous Na2SO4, and concentrated under vacuum. The crude product was purified by column chromatography eluting with petroleum ether/ethyl acetate (3:1) to give 3a. Products 3b-3t and 6 were obtained in a similar manner.

References:

Zhang, Xinying;Gao, Lin;Wang, Zhangxin;Fan, Xuesen [Synthetic Communications,2015,vol. 45,# 21,p. 2426 - 2435] Location in patent:supporting information