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Substitution substituted benzenes

Cheng Y-W and Dunbar R C 1995 Radiative association kinetics of methyl-substituted benzene ions J. Rhys. Chem. 99 10 802-7... [Pg.1360]

A point in case is provided by the bromination of various monosubstituted benzene derivatives it was realized that substituents with atoms carrying free electron pairs bonded directly to the benzene ring (OH, NH2, etc) gave 0- and p-substituted benzene derivatives. Furthermore, in all cases except of the halogen atoms the reaction rates were higher than with unsubstituted benzene. On the other hand, substituents with double bonds in conjugation with the benzene ring (NO2, CHO, etc.) decreased reaction rates and provided m-substituted benzene derivatives. [Pg.7]

A is a parameter that can be varied to give the correct amount of ionic character. Another way to view the valence bond picture is that the incorporation of ionic character corrects the overemphasis that the valence bond treatment places on electron correlation. The molecular orbital wavefimction underestimates electron correlation and requires methods such as configuration interaction to correct for it. Although the presence of ionic structures in species such as H2 appears coimterintuitive to many chemists, such species are widely used to explain certain other phenomena such as the ortho/para or meta directing properties of substituted benzene compounds imder electrophilic attack. Moverover, it has been shown that the ionic structures correspond to the deformation of the atomic orbitals when daey are involved in chemical bonds. [Pg.145]

Dimethyl acetylenedicarboxylate (DMAD) (125) is a very special alkyne and undergoes interesting cyclotrimerization and co-cyclization reactions of its own using the poorly soluble polymeric palladacyclopentadiene complex (TCPC) 75 and its diazadiene stabilized complex 123 as precursors of Pd(0) catalysts, Cyclotrimerization of DMAD is catalyzed by 123[60], In addition to the hexa-substituted benzene 126, the cyclooctatetraene derivative 127 was obtained by the co-cyclization of trimethylsilylpropargyl alcohol with an excess of DMAD (125)[6l], Co-cyclization is possible with various alkenes. The naphthalene-tetracarboxylate 129 was obtained by the reaction of methoxyallene (128) with an excess of DMAD using the catalyst 123[62],... [Pg.487]

The name phenylene o-, m-, or p-) is retained for the radical —C5H4—. Bivalent radicals formed from substituted benzene derivatives and having the free valences at ring atoms are named as substituted phenylene radicals, with the carbon atoms having the free valences being numbered 1,2-, 1,3-, or 1,4-, as appropriate. [Pg.6]

Table 7.9 Electronic Absorption Bands for Representative Chromophores Table 7.10 Ultraviolet Cutoffs of Spectrograde Solvents Table 7.11 Absorption Wavelength of Dienes Table 7.12 Absorption Wavelength of Enones and Dienones Table 7.13 Solvent Correction for Ultraviolet-Visible Spectroscopy Table 7.14 Primary Bands of Substituted Benzene and Heteroaromatics Table 7.15 Wavelength Calculation of the Principal Band of Substituted Benzene Derivatives... Table 7.9 Electronic Absorption Bands for Representative Chromophores Table 7.10 Ultraviolet Cutoffs of Spectrograde Solvents Table 7.11 Absorption Wavelength of Dienes Table 7.12 Absorption Wavelength of Enones and Dienones Table 7.13 Solvent Correction for Ultraviolet-Visible Spectroscopy Table 7.14 Primary Bands of Substituted Benzene and Heteroaromatics Table 7.15 Wavelength Calculation of the Principal Band of Substituted Benzene Derivatives...
Table 7.53 Carbon-13 Chemical Shifts in Substituted Benzenes 7.104... Table 7.53 Carbon-13 Chemical Shifts in Substituted Benzenes 7.104...
TABLE 7.14 Primary Bands of Substituted Benzene and Heteroaromatics In methanol. [Pg.712]

TABLE 7.15 Wavelength Calculation of the Principal Band of Substituted Benzene Derivatives In ethanol. [Pg.713]

The recurring para-substituted benzene rings and sulfur atoms form a symmetrical rigid backbone. [Pg.1021]

Upon treatment with suitable cobalt complexes, methylbutynol cyclizes to a 1,2,4-substituted benzene. Nickel complexes give the 1,3,5-isomer (196), sometimes accompanied by linear polymer (25) or a mixture of tetrasubstituted cyclooctatetraenes (26). [Pg.113]

Neither benzenepentacarboxylic acid nor mellitic acid are manufactured commercially, but synthetic mellitic acid can be purchased as a laboratory chemical (99). Both can be synthesized by oxidizing the corresponding methylbenzenes or other substituted benzenes, and both are present in trace amounts after oxidation of coal or coal-like substances. [Pg.500]

Reactions of acetylene and iron carbonyls can yield benzene derivatives, quinones, cyclopentadienes, and a variety of heterocycHc compounds. The cyclization reaction is useful for preparing substituted benzenes. The reaction of / fZ-butylacetylene in the presence of Co2(CO)g as the catalyst yields l,2,4-tri-/ f2 butylbenzene (142). The reaction of Fe(CO) and diphenylacetylene yields no less than seven different species. A cyclobutadiene derivative [31811 -56-0] is the most important (143—145). [Pg.70]

When the pyrazole ring bears two adjacent functional substituents, it reacts like an o-substituted benzene. For example, 4,5-diaminopyrazoles behave similarly to... [Pg.271]

We will return to the aromatic stabilization of benzene in more detail in Chapter 9, but substituted benzenes provide excellent examples of how proper use of the resonance concept can be valuable in predicting reactivity. Many substituents can be readily classified... [Pg.12]

Fig. 4.3. Resonance, field, and inductive components of substituent effects in substituted benzenes. Fig. 4.3. Resonance, field, and inductive components of substituent effects in substituted benzenes.
Other matters that are important include the ability of the electrophile to select among the alternative positions on a substituted aromatic ring. The relative reactivity of different substituted benzenes toward various electrophiles has also been important in developing a firm understanding of electrophilic aromatic substitution. The next section considers some of the structure-reactivity relationships that have proven to be informative. [Pg.557]

Table 10.1. Energy Changes for Isodesmic Proton-Transfer Reactions of Substituted Benzenes"... Table 10.1. Energy Changes for Isodesmic Proton-Transfer Reactions of Substituted Benzenes"...
Fig. 10.3. Orbital coefficients for HOMO and next highest n orbital for some substituted benzenes. (From CNDO/2 ealculations. Ortho and meta eoefficients have been averaged in the case of the unsymmetrical methoxy and formyl substituents. Orbital energies are given in atomic units.)... Fig. 10.3. Orbital coefficients for HOMO and next highest n orbital for some substituted benzenes. (From CNDO/2 ealculations. Ortho and meta eoefficients have been averaged in the case of the unsymmetrical methoxy and formyl substituents. Orbital energies are given in atomic units.)...
Fig. 10.4. Total 7i-electron density for some substituted benzenes. [From STO-3G calculations as reported by W. J. Hehre, L. Radom, and J. A. Pople, J. Am. Chem. Soc. 94 1496 (1972).]... Fig. 10.4. Total 7i-electron density for some substituted benzenes. [From STO-3G calculations as reported by W. J. Hehre, L. Radom, and J. A. Pople, J. Am. Chem. Soc. 94 1496 (1972).]...
Table 10.3. Isomer Proportions in the Nitration of Some Substituted Benzenes ... Table 10.3. Isomer Proportions in the Nitration of Some Substituted Benzenes ...
Addition of nucleophiles sueh as ammonia or alcohols or their conjugate bases to benzynes takes place very rapidly. These nueleophilie additions are believed to involve eapture of the nueleophile, followed by protonation to give the substituted benzene. ... [Pg.594]

The table below gives first-order rate constants for reaction of substituted benzenes with w-nitrobenzenesulfonyl peroxide. From these data, calculate the overall relative reactivity and partial rate factors. Does this reaction fit the pattern of an electrophilic aromatic substitution If so, does the active electrophile exhibit low, moderate, or high substrate and position selectivity ... [Pg.598]

Irradiation of solutions of alkenes in benzene or substituted benzenes gives primarily 1 1 adducts in which the alkene bridges meta positions of the aromatic ring. ... [Pg.780]


See other pages where Substitution substituted benzenes is mentioned: [Pg.200]    [Pg.525]    [Pg.533]    [Pg.3]    [Pg.240]    [Pg.103]    [Pg.75]    [Pg.90]    [Pg.486]    [Pg.710]    [Pg.15]    [Pg.850]    [Pg.309]    [Pg.38]    [Pg.116]    [Pg.35]    [Pg.36]    [Pg.253]    [Pg.11]    [Pg.8]    [Pg.211]    [Pg.251]    [Pg.560]    [Pg.571]   
See also in sourсe #XX -- [ Pg.960 , Pg.961 ]




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2-azulenyl-substituted benzenes

5-Substituted pyrazol-3 benzene

6-azulenylethynyl-substituted benzenes

8 term substituted benzenes

A Uracil to Substituted Benzene Transformation

Acceptor-substituted benzenes

Acetonitrile benzene, substituted

Alkoxy-substituted benzenes, oxidation

Alkyl groups substituted benzenes

Alkyl-Substituted Benzenes Homologous

Alkyl-substituted benzene

Arenediazonium salts substituted benzene synthesis using

Arenes => substituted benzenes

Aromatic Compounds—Substituted Benzene Rings

Aromatic Substitution by Electrophiles (Lewis Acids, E 2 Electrophilic Substitutions in Syntheses of Benzene erivatives

Aromatic substitution of benzene

Base metal benzenes, substituted, from

Benzenamine Substituted benzenes

Benzene Electrophilic aromatic substitution reactions

Benzene Heterobenzenes Substituted benzenes

Benzene Nucleophilic aromatic substitution reactions

Benzene alkyl substituted, oxidation

Benzene and Aromaticity Electrophilic Aromatic Substitution

Benzene and Substituted Benzenes

Benzene aromatic substitution

Benzene aromatic substitution reactions

Benzene derivatives electrophilic aromatic substitution

Benzene derivatives substituted

Benzene derivatives substitution

Benzene derivatives substitution reactions

Benzene dimer substituted

Benzene electrophilic aromatic substitution, product

Benzene electrophilic substitution

Benzene electrophilic substitution reactions

Benzene methoxy-substituted

Benzene nucleophilic aromatic substitution

Benzene ortho-substituted

Benzene radical substitution

Benzene ring, substitution

Benzene ring, substitution patterns

Benzene rings substituted

Benzene substituted benzenes

Benzene substitution

Benzene substitution

Benzene substitution pattern

Benzene substitution products

Benzene substitution reaction

Benzene substitution reactions, resistance

Benzene with substituted aromatics

Benzene, absorption spectrum substituted

Benzene, acylation alkyl substituted, nitration

Benzene, acylation bromine substitution

Benzene, halo-, halogen displacement nitro-, nucleophilic substitution

Benzene, pentamethylradical cation side chain substitution

Benzene, trifluoromethyl-substituted

Benzene, tris aromatic nucleophilic substitution

Benzenes donor-substituted

Benzenes substituted, reactivity

Benzenes, fluorine-substituted

Benzenes, substituted C” substituent

Benzenes, substituted X: substituent

Benzenes, substituted Z substituent

Benzenes, substituted bromo

Benzenes, substituted electrophilic substitutions

Benzenes, substituted nucleophilic substitutions

Benzenes, substituted, condensed-phase

Benzenes, substituted, cyclizations

Benzenes, substituted, from

Benzenes, substituted, from formation

Benzenes, substituted, synthesis

Bromination of substituted benzenes

Chemical Shifts in Substituted Benzenes

Chemistry of Benzene Electrophilic Aromatic Substitution

Chlorination, benzene substituted benzenes

Cyclic mechanism alkyl-substituted benzenes

Cyclotrimerizations substituted benzenes

DRUGS BASED ON A SUBSTITUTED BENZENE RING

Deprotonative metalation substituted benzenes

Di-and poly-substituted derivatives of benzene

Di-substituted benzene derivatives

Disubstituted Benzenes Ortho, Meta, and Para Substitution

Electrophiles with substituted benzenes

Electrophilic Aromatic Substitution in Polysubstituted Benzenes

Electrophilic Aromatic Substitution on Substituted Benzenes

Electrophilic Attack on C-Substituted Benzenes

Electrophilic Attack on X-Substituted Benzenes

Electrophilic Attack on Z-Substituted Benzenes

Electrophilic aromatic substitution benzene derivatives, nomenclature

Electrophilic aromatic substitution benzenes

Electrophilic aromatic substitution of benzene

Electrophilic aromatic substitution of substituted benzenes

Electrophilic substitution reaction monosubstituted benzene

Electrophilic substitution, of benzene

Fused benzene rings substituted

General Aspects of Substitution on a Benzene Nucleus

Halogen-substituted benzen

Hexa-substituted benzene derivatives

How Do Existing Substituents on Benzene Affect Electrophilic Aromatic Substitution

Hydrogen substitution, benzene nucleus

Hydrogenation of Alkyl-Substituted Benzenes

Hydroxy- and methoxy-substituted benzenes

Hydroxylation of Benzene and Substituted Benzenes

In substituted benzenes

Industrial substituted benzene derivatives

Infrared spectra, of substituted benzenes

Ionization potential of substituted benzenes

Isomerism substituted benzenes

Isomers substituted benzene

Key to Success Synthetic Strategies Toward Substituted Benzenes

Limitations on Electrophilic Substitution Reactions with Substituted Benzenes

Metallation of Hetero-Substituted Benzene and Naphthalene with BuLi TMEDA in Hexane

Methyl-substituted benzenes, radiative

Monosubstituted benzenes substitution

Nitration of Substituted Benzene Derivatives

Nitration substituted benzene derivatives

Nitro groups, substituted benzenes

Nitro groups, substituted benzenes reduction

Nucleophilic Attack on Z-Substituted Benzenes

Nucleophilic substitution of benzenes, nitro

Orientation effect, in substituted benzenes

Oxidation and Reduction of Substituted Benzenes

Oxidation of substituted benzenes

P-substituted benzenes

Phenyl-azolones, electrophilic substitution often occurs in the benzene

Physical Properties of Substituted Benzenes

Primary Band of Substituted Benzene and Heteroaromatics

Primary amines with substituted benzenes

Reactions of Benzene and Substituted Benzenes

Reactions of Substituted Benzenes

Reactivity of substituted benzenes

Reduction of substituted benzenes

Regioselectivity substituted benzenes

Representative Electrophilic Aromatic Substitution Reactions of Benzene

Rhodium, selectivity substituted benzenes

SUBSTITUTION ON THE BENZENE NUCLEUS

Simple Substituted Benzene Analytes

Structure-Reactivity Relationships for Substituted Benzenes

Substituted Benzenes The Alvarez-Manzaneda Synthesis of -Taiwaniquinone

Substituted Benzenes, Naphthalenes, and Anthracenes

Substituted Derivatives of Benzene and Their Nomenclature

Substituted benzene derivative synthesis

Substituted benzenes

Substituted benzenes Birch reduction

Substituted benzenes Friedel-Crafts electrophiles

Substituted benzenes arene

Substituted benzenes aromatic compounds

Substituted benzenes aromatic substitution reactions

Substituted benzenes directing effects

Substituted benzenes directing power

Substituted benzenes groups that donate electrons

Substituted benzenes groups that withdraw electrons

Substituted benzenes halogen substituents

Substituted benzenes infrared bending vibrations

Substituted benzenes meta substitution, definition

Substituted benzenes para substitution, definition

Substituted benzenes photosubstitution

Substituted benzenes physical properties

Substituted benzenes synthetic strategies toward

Substituted benzenes vibrational spectra

Substituted benzenes, carbon atom reactivity with

Substituted benzenes, infrared spectra

Substituted divinyl benzene

Substitution of Benzene Rings

Substitution of benzene

Substitution pattern of benzene ring

Substitution reactions of benzene

Substitution reactions with benzene

Substitution, electrophilic monosubstituted benzenes

Synthesis of Benzene Derivatives Electrophilic Aromatic Substitution

Synthesis of Substituted Benzenes

The synthesis of substituted benzenes

Toluene Dioxygenase Indigo or Prostaglandins from Substituted Benzenes via cis-Dihydrodiols

Torsional Isomerism of Substituted Benzenes

Vibrational spectroscopy substituted benzenes

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