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!

82619-63-4

2-CHLORO-5-FURAN-2-YL-PYRAZINE synthesis

2synthesis methods
-

Yield:82619-63-4 45%

Reaction Conditions:

with trichlorophosphate for 3 h;Heating / reflux;

Steps:

1.C (4-Cyclobutyl-[1,4]diazepan-1-yl)-[5-(4-fluoro-phenoxy)-pyrazin-2-yl]-methanone

Step C: 2-Chloro-5-furan-2-yl-pyrazine. A solution of 5-furan-2-yl-pyrazin-2-ol (7.20 g, 44.4 mmol) in POCl3 (60 mL) was heated at reflux for 3 h. The reaction was allowed to cool, and excess POCl3 was removed by rotary evaporation. The residue was quenched with ice and water. The acidic mixture was basified with aqueous NaOH to pH 10, and the product was extracted with CHCl3. The combined organic extracts were dried (Na2SO4) and concentrated to provide the title chloropyrazine (3.62 g, 45%). 1H NMR (500 MHz, CDCl3): δ 8.73 (d, J=1.4 Hz, 1H), 8.52 (d, J=1.4 Hz, 1H), 7.60 (d, J=1.7 Hz, 1H), 7.14 (d, J=3.4 Hz, 1H), 6.58 (dd, J=3.5, 1.8 Hz, 1H).

References:

US2009/131416,2009,A1 Location in patent:Page/Page column 9