REACTIONS OF PHENYL-SUBSTITUTED HETEROCYCLIC COMPOUNDS: III. FREE-RADICAL PHENYLATION OF 1-PHENYLPYRAZOLE

1963 ◽  
Vol 41 (8) ◽  
pp. 2086-2094 ◽  
Author(s):  
Brian M. Lynch ◽  
Misbahul Ain Khan
Keyword(s):  
Free Radical ◽  
Benzoyl Peroxide ◽  
Phenyl Ring ◽  
Heterocyclic Compounds ◽  
Pyrazole Ring ◽  
Free Valence ◽  
Resonance Theory ◽  
Phenyl Radicals ◽  
Radical Phenylation

Phenyl radicals furnished by benzoyl peroxide attack both rings of 1-phenylpyrazole, and the orientation of substitution has been examined using gas–liquid partition chromatography.Substitution occurs at all positions of the phenyl ring, although predominantly at the ortho positions, while attack in the pyrazole ring is confined to the 3-position. The results are in agreement with the suggestion that the free valence at a given position is a major factor in determining the orientation of free-radical phenylation of 1-phenylpyrazole, but in conflict with predictions from resonance theory.

Aromatic substitution. XV. The homolytic methylation of pyridine and 3- and 4-picoline

1967 ◽  
Vol 45 (5) ◽  
pp. 509-513 ◽  
Author(s):  
R. A. Abramovitch ◽  
K. Kenaschuk
Keyword(s):  
Free Radical ◽  
Methyl Radicals ◽  
Aromatic Substitution ◽  
Phenyl Radicals

The ratios of isomers formed in the free-radical methylation of pyridine and 3- and 4-picoline have been determined and the results compared with the corresponding phenylations. The results support the concept that methyl radicals are more nucleophilic than phenyl radicals.

scholarly journals Effect of Ferocene Concentration on the Percent Conversion and Molecular Weight of Poly(Methyl Methacrylate) Homopolymers

2017 ◽  
Vol 14 (2) ◽  
pp. 311-319
Author(s):  
Baghdad Science Journal
Keyword(s):  
Molecular Weight ◽  
Free Radical ◽  
Methyl Methacrylate ◽  
Benzoyl Peroxide ◽  
Radical Polymerization ◽  
Free Oxygen ◽  
Poly Methyl Methacrylate ◽  
Methacrylate Monomer ◽  
Percent Conversion ◽  
Methyl Methacrylate Monomer

This research is addressing the effect of different ferrocene concentration (0.00, 2.15x10-3, 4.30x10-3, 8.60x10-3, and 12.9x10-3) on the bulk free radical polymerization of methyl methacrylate monomer in benzene using benzoyl peroxide as initiator. The polymerization was conducted at 60º C under free oxygen atmosphere. The resulting polymers were characterized by FTIR. The results were compared with the presence and absence of ferrocene at 10% conversion. The %conversion was 3.04% with no ferrocene present in the polymerization medium and its increase to 9.06 with a first lowest ferrocene concentration added, i.e. 2.15 x10-3mol/l. This was positively reflected on the poly(methyl methacrylate) molecular weight measured by viscosity technique, especially in the presence of ferrocene.

scholarly journals Solvent Effect on the Free Radical Phenylation with Phenylazotriphenylmethane

1973 ◽  
Vol 46 (2) ◽  
pp. 546-550 ◽  
Author(s):  
Michio Kobayashi ◽  
Hiroshi Minato ◽  
Nobuko Watanabe
Keyword(s):  
Free Radical ◽  
Solvent Effect ◽  
Radical Phenylation

scholarly journals Diethyl [(2-chloroanilino)(1,3-diphenyl-1H-pyrazol-4-yl)methyl]phosphonate

2013 ◽  
Vol 69 (2) ◽  
pp. o182-o182
Author(s):  
G. Suresh ◽  
A. Nandakumar ◽  
V. Sabari ◽  
P. T. Perumal ◽  
S. Aravindhan
Keyword(s):  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Title Compound ◽  
Phenyl Ring ◽  
Pyrazole Ring ◽  
Compound C ◽  
The Mean

In the title compound, C26H27ClN3O3P, the mean plane of the central pyrazole ring forms a dihedral angle of 71.37 (14)° with the chlorophenyl ring. In the crystal, molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers withR22(10) ring motifs. The 3-phenyl ring is disordered with four C atoms occupying two sets of sites with an occupancy ratio of 0.748 (4):0.252 (4).

Methyl 5-phenyl-1H-pyrazole-3-carboxylate

2007 ◽  
Vol 63 (11) ◽  
pp. o4474-o4474 ◽  
Author(s):  
Guanghua Zhou ◽  
Yue An ◽  
Jing Han ◽  
Maofa Ge ◽  
Yongheng Xing
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Carboxylic Acid ◽  
Title Compound ◽  
Phenyl Ring ◽  
Pyrazole Ring ◽  
Compound C ◽  
Centroid Distance ◽  
Different Types ◽  
Neighboring Molecule

The title compound, C11H10N2O2, was prepared by the esterfication of 5-phenyl-1H-pyrazole-3-carboxylic acid with methanol. The phenyl ring is rotated out of the pyrazole plane, forming a dihedral angle of 6.4 (1)°. The crystal structure is stabilized by intermolecular aromatic π–π interactions [with a centroid–centroid distance of 3.862 (3) Å between the pyrazole ring and the benzene ring of a neighboring molecule], and by three different types of hydrogen bond (N—H...N, N—H...O and C—H...O).

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