2767-91-1Relevant articles and documents
Structures, Lewis Acidities, Electrophilicities, and Protecting Group Abilities of Phenylfluorenylium and Tritylium Ions
Follet, Elsa,Mayer, Peter,Berionni, Guillaume
supporting information, p. 623 - 630 (2017/01/18)
The isolation, characterization, and the first X-ray structures of a fluorenylium ion and its Lewis adducts with nitrogen- and phosphorus-centered Lewis bases are reported. Kinetics of the reactions of a series of fluorenylium ions with reference π-, σ-, and n-nucleophiles of various sizes and nucleophilicities allowed the interplay between electronic and structural parameters on the electrophilicities of these planarized tertiary carbenium ions to be elucidated. Structure–reactivity correlations and extensive comparisons of their reactivities with those of di- and triarylcarbenium ions are described. Quantitative determination of the electrofugalities of fluorenylium ions revealed to which extent they are complementing tritylium ions as protecting groups and how their tuning is possible. Determination of the equilibrium constants of the Lewis adducts formation between pyridines of calibrated Lewis basicities and phenylfluorenylium and tritylium ions allowed the determination of their Lewis acidities and to showcase the potential of these carbon-centered Lewis acids in catalysis.
Some reactions of pyridinium salts derived from trichloromethylarenes with N- and C-nucleophiles
Belen'kii,Poddubnyi,Luiksaar,Krayushkin
, p. 1172 - 1176 (2007/10/03)
The reaction of N-(4-pyridyl)pyridinium and 4-chloropyridinium salts obtained from 1-trichloromethyl-2,4,6-trimethylbenzene and pyridine with N-nucleophiles such as piperidine and morpholine and with C-nucleophiles such as N,N-dimethylaniline and indole proceeds through hetarylation and gives the corresponding 4-substituted pyridines. N-(α,α-Dichlorobenzyl)pyridinium and N,N'-(α-chlorobenzylidene)bispyridinium salts obtained from trichloromethylbenzene do not undergo hetarylation.
Photochemical Induced Formation of α-Alkylamino or Alkylaminyl Radicals From Secondary Amines: Reaction with 4-Pyridinecarbonitrile
Caronna, Tullio,Morrocchi, Sergio
, p. 975 - 977 (2007/10/02)
The direct photolysis at 254 nm of 4-pyridinecarbonitrile in the presence of some aliphatic secondary amines brought to the substitution of the CN group and to the formation of 4-α-alkylaminopyridines, whereas the irradiation in the presence of benzophenone at 350 nm yields 4-alkylaminylpyridines and 4-diphenylketylpyridine.A mechanism is proposed to explain the different course of the reaction under the two different conditions.
