Relative Rates of the Aluminum Chloride-Catalyzed Benzoylation of the Monoalkylbenzenes in Nitrobenzene Solution. Importance of Carbon-to-Carbon Hyperconjugation in Alkyl Substituents1,2

1958 ◽  
Vol 23 (3) ◽  
pp. 414-416 ◽  
Author(s):  
HERBERT C. BROWN ◽  
BRIAN A. BOLTO ◽  
FREDERICK R. JENSEN
Keyword(s):  
Aluminum Chloride ◽  
Nitrobenzene Solution

THE FRIES REARRANGEMENT OF PHENYL ISOBUTYRATE

1956 ◽  
Vol 34 (7) ◽  
pp. 851-855 ◽  
Author(s):  
T. I. Briggs ◽  
G. G. S. Dutton ◽  
E. Merler
Keyword(s):  
Aluminum Chloride ◽  
Room Temperature ◽  
Alternative Route ◽  
Nitrobenzene Solution ◽  
Anhydrous Aluminum Chloride ◽  
Fries Rearrangement ◽  
Direct Acylation

Phenyl isobutyrate has been found to undergo a normal Fries rearrangement with anhydrous aluminum chloride at 140 °C. to give a mixture of 2-hydroxy-(40%) and 4-hydroxy-isobutyrophenone (11%). When the reaction was carried out in nitrobenzene solution at room temperature the 4-isomer was formed in 86% yield. Methylation of these compounds furnished 2- and 4-methoxy-isobutyrophenone, identical with the compounds obtained by direct acylation of anisole. Reduction of the hydroxy-isobutyrophenones, which were also prepared by direct acylation of phenol, afforded an alternative route to the isobutylphenols. The orientation of each methoxy ketone was verified by oxidation to the corresponding acid.

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

Europium and cerium extraction by the nitrobenzene solution of dicarbolide in the presence of polyethylene glycols

1986 ◽  
Vol 51 (3) ◽  
pp. 498-515 ◽  
Author(s):  
Emanuel Makrlík ◽  
Petr Vaňura
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Organic Phase ◽  
Perchloric Acid ◽  
Equilibrium Constants ◽  
Polyethylene Glycols ◽  
Individual Species ◽  
Nitrobenzene Solution ◽  
Separation Factors ◽  
Equilibrium Data

Extraction of Eu3+ and Ce3+ microamounts from 0.1-0.4M perchloric acid by the nitrobenzene solution of dicarbolide H+[Co(C2B9H11)2]- in the presence of polyethylene glycols (Mr = 200, 300, 400) has been studied. The equilibrium data and the typical maxima on the dependence of the metal distribution ratio on the total analytical concentration of polyethylene glycol in the system can be explained assuming that the species ML3+org, ML3+2org, ML3+3org, MLH2+-1org, and HL+org (where M3+ = Eu3+, Ce3+; L = polyethylene glycol) are extracted into the organic phase. The values of extraction and equilibrium constants in the organic phase were determined and the effect of the polyethylene glycol molecular weight on the equilibrium constants and on the abundances of individual species in the organic phase is discussed. It has been found that the addition of polyethylene glycol to the acid - nitrobezene - dicarbolide system increases the values of the separation factors αCe/Eu.

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