15516-72-0

Upstream product

• 21650-49-7 (E)-1-(4-methoxyphenyl)-2-phenyldiazene 
• 108-95-2 phenol 
• 1689-82-3 trans-4-hydroxyazobenzene 
• 100-58-3 phenylmagnesium bromide 

Downstream Products

• 21650-49-7 (E)-1-(4-methoxyphenyl)-2-phenyldiazene 

Relevant academic research and scientific papers

A non-standard temperature dependence of the order parameter of the 5CB liquid crystal doped with an azo-derivative

The effects of the cis and trans form of the 4-OMe-phenylazobenzene at 1% and 7% mole fraction on order, mesophase stability and dynamics of the 5CB liquid crystal were studied using the ESR spin probe technique. The presence of the trans azo-derivative induced a downshift of the nematic-isotropic transition temperature TNI which increased with the concentration but did not change the dependence of the order parameter on the reduced temperature. The cis isomer caused even larger TNI shifts, determining a marked decrease of the order parameter with a peculiar dependence on the reduced temperature, quite different from the standard Haller-type behavior. The spin probe dynamics appeared instead to be essentially unchanged by the presence of the azo-derivative.

Kinetics and energetics of thermal cis-trans isomerization of a resonance-activated azobenzene in BMIM-based ionic liquids for PF6-/Tf2N- Comparison

BMIM PF6 (1-butyl-3-methylimidazolium hexafluorophosphate) and BMIM Tf2N (1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) are two conventional room-temperature ionic liquids widely employed and investigated as reaction media. Despite the presence of the same imidazolium ring in their structure they are different in many chemical and physical properties due to the nature of the anions. The thermal cis-trans isomerization of an electronically activated azobenzene have been used as reaction model to compare the behavior of PF6- and Tf2N-. Rotation is the mechanism by which the investigated azobenzene is converted into the trans isomer spontaneously in the dark both in BMIM PF6 and in BMIM Tf2N. The kinetic rate constants of the process have been determined at different temperatures and the activation energies of the reaction have been calculated according to the Arrhenius and Eyring equations. The results presented herein highlight different solute-solvent interactions involving the PF6- and Tf2N- anions during the cis-trans isomerization.

Design of phase-transition molecular solar thermal energy storage compounds: compact molecules with high energy densities

A series of compact azobenzene derivatives were investigated as phase-transition molecular solar thermal energy storage compounds that exhibit maximum energy storage densities around 300 J g?1. The relative size and polarity of the functional g

Through-space 19F-19F spin-spin coupling in ortho-fluoro Z -azobenzene

We report through-space (TS) 19F-19F coupling for ortho-fluoro-substituted Z-azobenzenes. The magnitude of the TS-coupling constant (TSJFF) ranged from 2.2-5.9 Hz. Using empirical formulas reported in the literature, these coupling constants correspond to non-bonded F-F distances (dFF) of 3.0-3.5 ?. These non-bonded distances are significantly smaller than those determined by X-ray crystallography or density functional theory, which argues that simple models of 19F-19F TS spin-spin coupling solely based dFF are not applicable. 1H, 13C and 19F data are reported for both the E and Z isomers of ten fluorinated azobenzenes. Density functional theory [B3YLP/6-311++G(d,p)] was used to calculate 19F chemical shifts, and the calculated values deviated 0.3-10.0 ppm compared with experimental values.

Role of Solvent and Effect of Substituent on Azobenzene Isomerization by Using Room-Temperature Ionic Liquids as Reaction Media

The effects of a para substituent, as the electron-donating -OCH3 and -OtBu groups and the electron-withdrawing -Br and -F atoms, on azobenzene isomerization have been investigated in a series of imidazolium ionic liquids (BMIM PF6,

Gold nanoparticle catalysis of the cis-trans isomerization of azobenzene

Ablated, "pseudo-naked" gold nanoparticles (AuNPs) catalyze the cis-trans isomerization of substituted azobenzenes. para-Substitution was found to affect the rate of isomerization, suggesting the participation of AuNP-mediated electron transfer in the isomerization mechanism. The Royal Society of Chemistry 2013.

Concentration dependent photodimerization of azobenzenes in solution

Cis-trans photoisomerization of azobenzenes in higher concentrations proceeds through a bimolecular reaction process, probably involving the dimer biradical intermediates, in competition with a unimolecular isomerization process, which is the predominant reaction in lower concentrations.

Preparation of diazenes by electrophile C-coupling reactions of dry arenediazonium o-benzenedisulfonimides with Grignard reagents

The diaryldiazenes (19 examples) and aryl(tertbutyl)diazenes (3 examples) 3 were prepared by electrophilic C-coupling reactions of dry arenediazonium o-benzenedisulfonimides 1 with Grignard reagents. The reactions were carried out in anhyd THF at -78°C un