氟化氢吡啶

 

CAS 62778-11-4

结构式:

别名:

分子式:  C5H5N.HF

分子量:  99.11

Physical And Chemical Properties:

State: Liquid

Color: Colorless to brown Solubility in water, reacts violently

Boiling point/range°C: 50/lmm Relative density: l.lg/cm3

.

Stability & Reactivity:


Pyridine HF is a form of hydrogen fluoride used in pharmaceutical manufacturing and fluorine synthesis.

Stable under recommended transport or storage conditions and normal conditions. Avoid: Heat, fire and

water; strong bases, alkali metals, strong oxidizing agents, metals and strong acids. Reacts violently

with water. During combustion, may emit toxic carbon dioxide / carbon fumes.

 

About Pyridine HF:

 

Some of the problems with HF can be minimized by combination with an amine, thereby making the reagent much less volatile and safe to use in ordinary lab glassware. Such reagents are suitable for desilylation and displacement of alkyl and aryl halides. The electron density of the fluoride anion is somewhat reduced compared to HF itself. These reagents are more effective when less electrophilic substrates are activated for nucleophilic attack. Epoxides, activated by their ring strain, convert well to 1,2-fluoroalcohols. Olefins, activated with an oxidant like NBS, convert to 1,2-fluorobromides (Markovnikov addition of fluoride). Either of these products can be converted to fluoro-olefins, which can be subsequently converted to difluorides. The same combination of reagents can convert thio ketals to geminal difluorides. Alcohols and phenols, through their intermediate xanthates, are converted to trifluoromethyl ethers. 1

1 (Org. Process Res. Dev., 2008, 12, 308 and references therein).