Alkyl Substituent Effects on Molecular Packing and Optoelectronic Properties of 2,3-Dialkyltetracenes

2014 ◽  
Vol 87 (8) ◽  
pp. 915-921 ◽  
Author(s):  
Chitoshi Kitamura ◽  
Genki Ohe ◽  
Takeshi Kawase ◽  
Akinori Saeki ◽  
Shu Seki
Keyword(s):  
Substituent Effects ◽  
Alkyl Substituent ◽  
Molecular Packing ◽  
Optoelectronic Properties

Kinetic Study of Hydrolysis of Benzoates. Part XXVI. Variation of the Substituent Effect with Solvent in Alkaline Hydrolysis of Substituted Alkyl Benzoates

2006 ◽  
Vol 71 (11-12) ◽  
pp. 1557-1570 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Ilmar A. Koppel
Keyword(s):  
Kinetic Study ◽  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Substituent Effect ◽  
Substituent Effects ◽  
Alkyl Substituent ◽  
Solvent Parameters ◽  
Substituent Constants ◽  
Hydrolysis Of ◽  
Main Factor

The second-order rate constants k2 (dm3 mol-1 s-1) for the alkaline hydrolysis of substituted alkyl benzoates C6H5CO2R have been measured spectrophotometrically in aqueous 0.5 M Bu4NBr at 50 and 25 °C (R = CH3, CH2Cl, CH2CN, CH2C≡CH, CH2C6H5, CH2CH2Cl, CH2CH2OCH3, CH2CH3) and in aqueous 5.3 M NaClO4 at 25 °C (R = CH3, CH2Cl, CH2CN, CH2C≡CH). The dependence of the alkyl substituent effects on different solvent parameters was studied using the following equations:      ∆ log k = c0 + c1σI + c2EsB + c3∆E + c4∆Y + c5∆P + c6∆EσI + c7∆YσI + c8∆PσI     ∆ log k = c0 + c1σ* + c2EsB + c3∆E + c4∆Y + c5∆P + c6∆Eσ* + c7∆Yσ* + c8∆Pσ* .  ∆ log k = log kR - log kCH3. σI and σ* are the Taft inductive and polar substituent constants. E, Y and P are the solvent electrophilicity, polarity and polarizability parameters, respectively. In the data treatment ∆E = ES - EH2O , ∆Y = YS - YH2O , ∆P = PS - PH2O were used. The solvent electrophilicity, E, was found to be the main factor responsible for changes in alkyl substituent effects with medium. When σI constants were used, variation of the polar term of alkyl substituents with the solvent electrophilicity E was found to be similar to that observed earlier for meta and para substituents, but twice less when σ* constants were used. The steric term for alkyl substituents was approximately independent of the solvent parameters.

Alkyl Substituent effects on the stability of protonated benzene

1974 ◽  
Vol 96 (22) ◽  
pp. 7162-7163 ◽  
Author(s):  
Warren J. Hehre ◽  
Robert T. McIver ◽  
John A. Pople ◽  
Paul v. R. Schleyer
Keyword(s):  
Substituent Effects ◽  
Alkyl Substituent ◽  
The Stability

Substitution site effect of naphthyl substituted anthracene derivatives and their applications in organic optoelectronics

2020 ◽  
Vol 8 (44) ◽  
pp. 15597-15602
Author(s):  
Jie Li ◽  
Deyang Ji ◽  
Yongxu Hu ◽  
Mingxi Chen ◽  
Jinyu Liu ◽  
...  
Keyword(s):  
Site Effect ◽  
Molecular Packing ◽  
Optoelectronic Properties ◽  
Organic Optoelectronics ◽  
Substitution Site ◽  
Significant Difference ◽  
Anthracene Derivatives

Two different naphthyl substituted anthracene derivatives were synthesized. A tiny change of the substitution site of the naphthyl group leads to a significant difference of the molecular packing and exerts great impact on optoelectronic properties.

Alkyl Substituent Effects on the Conductivity of Polyaniline

2004 ◽  
Vol 14 (5) ◽  
pp. 479-486 ◽  
Author(s):  
N. A. Zaidi ◽  
J. P. Foreman ◽  
G. Tzamalis ◽  
S. C. Monkman ◽  
A. P. Monkman
Keyword(s):  
Substituent Effects ◽  
Alkyl Substituent

Diastereoselective alkylations of chiral, phosphorus-stabilized carbanions: N-alkyl substituent effects in P-alkyl-1,3,2-diazaphosphorinane 2-oxides

2000 ◽  
Vol 78 (6) ◽  
pp. 673-688 ◽  
Author(s):  
Scott E Denmark ◽  
Jung-Ho Kim
Keyword(s):  
Systematic Study ◽  
Substituent Effects ◽  
Alkyl Substituent

A systematic study of the diastereoselective alkylation of anions derived from racemic N-substituted P-alkyl 1,3,2-diazaphosphorinane 2-oxides was carried out with variation of the N-substituent. High diastereoselectivity for the methylation of a P-benzyl anion has been achieved with N-neopentyl derivative 5d. Similarly, a P-ethyl anion derived from N-neopentyl derivative 6d showed high diastereoselectivity upon benzylation. The observed difference in alkylation diastereoselectivity between P-ethyl and P-benzyl anions for various N-alkyl substituents is discussed.Key words: phosphonamide-stabilized carbanions, alkylation, asymmetric, stereoselective, organolitihium.

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