Poly-4-vinylpyridinium Poly(Hydrogen Fluoride): A Solid Hydrogen Fluoride Equivalent Reagent
作者:George A. Olah、Xing-Ya Li、Qi Wang、G. K. Surya Prakash
DOI:10.1055/s-1993-25924
日期:——
Poly-4-vinylpyridinium poly(hydrogen fluoride) (PVPHF), containing 35-60% hydrogen fluoride by weight, was prepared as a solid hydrogen fluoride equivalent reagent. PVPHF with 60% hydrogen fluoride by weight was found to be a versatile fluorinating agent for the hydrofluorination and bromofluorination of alkenes and alkynes, fluorination of alcohols as well as other fluorination reactions. Low hydrogen fluoride content PVPHF (3 equivalents of hydrogen fluoride to 1 equivalent of 4-vinylpyridine unit) was also found to be an efficient reagent for bromofluorination of alkenes in the presence of 1,3-dibromo-5,5-dimethylhydantoin. Fluorosulfonic acid-modified PVPHF showed enhanced reactivities for the fluorination of secondary alcohols.
The Reaction of Phenyl(trichloromethyl)mercury with Substituted Norbornenes
作者:C. W. Jefford、D. T. Hill、J. Goré、B. Waegell
DOI:10.1002/hlca.19720550307
日期:1972.4.20
The addition of phenyl(trichloromethyl)mercury to five substituted norbornenes is described, and the results compared with those obtained with bicyclo[2.2.2]oct-2-ene and 3,3,5,5-tetramethylcyclopentene. The reaction proves to be useful for synthetic purposes, in that it leads usually to ring expansion. However, a possible disadvantage is that the addition step is sensitive to steric hindrance and