99久久中文字幕_1级黄色大片_九一香蕉国产在线观看AV_国产一级特黄AAAA级婬片_国产a毛片_av亚洲产国偷v产偷v自拍小说

Hydrogen fluoride-pyridine

0

category
Product
CAS No.
32001-55-1;62778-11-4
Purity
≥99%

Product Details

Name: Hydrogen fluoride-pyridine/PPHF/Pyridine Poly(hydrogen fluoride)/Olah's Reagent

CAS number : 32001-55-1; The 62778-11-4

Molecular formula:C5H5N.nHF(where n≥1)

Purity:≥99%

Appearance: Light yellow to reddish brown transparent liquid

Boiling point: 50℃/1mmHg

Free HF%: 65-70%

Packing: 1kg/ bottle, 25kg/ barrel, 50kg/ barrel

Use: fluorinated reagent

_________________________________________________________________________________________________________

Hydrogen fluoride-pyridine complex (PPHF) is an improvement on the application form and mode of hydrogen fluoride reagent, which can be simply regarded as hydrogen fluoride with a higher boiling point. The PPHF obtained by Olah reagent preparation method can stabilize the temperature of HF emission to about 55 ℃. Compared with anhydrous hydrogen fluoride, PPHF can probably be considered to have the same reaction, the reaction activity is slightly reduced, the selectivity is greatly increased, and the stereochemistry of the product may be different.

PPHF has been widely used in the fluorination ring opening reaction of oxygen - and nitrogen-containing ternary rings. The ring-opening reaction of epoxide fluoridation that can be accomplished by anhydrous hydrogen fluoride can also be accomplished by PPHF [2], and it has been found that PPHF can obtain better results in some reactions [3]. Usually the reaction can be carried out under very mild conditions with very high stereoselectivity and satisfactory yields (Equation 1)[4,5]. The stereochemistry of the fluorinated ring-opening product of the nitrogen-containing ternary ring is just complementary to the anhydrous hydrogen fluoride reagent (Equation 2)[6]

主站蜘蛛池模板: 裸体午夜一级视频 | 日韩一级片在线 | 国产三级毛片 | 日韩欧美中文字幕一区二区三区 | 一级做a爰性色毛片 | 日本一区二区久久精品 | 禁果av一区在线在观看 | 斗破苍穹在线免费 | 韩国免费视频 | 波波成人影院在线播放 | 91成人观看 | 国产精品一区二区女厕厕 | 日本高清久久一区二区三区 | 91精品国产经典在线观看 | 日本啊v在线 | 69成人免费视频无码专区 | 91在线麻豆 | 亚洲成人一区二区三区四区 | 久久久精品视频在线 | caop在线| 久久毛片免费看 | 亚洲成人精品在线 | 国产午夜精品免费一区二区三区 | 大地资源在线观看免费官网 | 在线观看黄色片 | 不卡日本 | 摊牌了我的五个哥哥是大佬短剧免费观看 | 亚洲国产黄色片 | 91色视频| 国产成人在线视频播放 | 26久久夜色精品国产噜26乱 | 亚洲人免费视频 | 欧美日韩国产在线 | 日本a网| 日本中文字幕二区 | 色国产一区 | 精品乱码久久久久 | 神马久草 | 国产精品揄拍一区二区久久 | 国产欧美日韩卡一 | 怡红院自拍 |