14528-67-7

Upstream product

• 136-64-1 terephthalohydrazide 
• 100-20-9 terephthaloyl chloride 
• 120-61-6 1,4-benzenedicarboxylic acid dimethyl ester 
• 100-21-0 terephthalic acid 
• 636-09-9 diethyl terephthalate 
• 201230-82-2 carbon monoxide 
• 624-38-4 para-diiodobenzene 
• 50-00-0 formaldehyd 
• 22693-31-8 azido(4-iodophenyl)methanone 
• 1075-49-6 4-ethenylbenzoic acid 

Downstream Products

• 104-49-4 1,4-diisocyanatobenzene 

Relevant academic research and scientific papers

FACILE SYNTHESIS OF AZIDES: CONVERSION OF HYDRAZINES USING DINITROGEN TETROXIDE

Various hydrazines such as aryl-, carbonyl-, and sulfonylhydrazine were reacted with dinitrogen tetroxide to give the corresponding azides in excellent yields under mild conditions at low temperature (-20 to ca.-40 deg C) in acetonitrile.

FLOW CHEMISTRY SYNTHESIS OF ISOCYANATES

The disclosure provides, inter alia, safe and environmentally-friendly methods, such as flow chemistry, to synthesize isocyanates, such as methylene diphenyl diisocyanate, toluene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and tetramethylxylene diisocyanate.

Visible Light-Induced Regioselective Cycloaddition of Benzoyl Azides and Alkenes to Yield Oxazolines

Visible light catalysis allows the regioselective synthesis of oxazolines in high yields. The mild photosensitized manifold leverages the intermolecular formation of oxazolines with a wide functional group tolerance on both benzoyl azides and alkenes part

Preferred Binding of Carboxylates by Chiral Urea Derivatives Containing α-Phenylethyl Group

An efficient, simple protocol for the synthesis of a new family of chiral ureas 1 – 4 is described. The binding properties of 1 – 4 toward different anion (acetate, benzoate, fluoride, and chloride) have been studied by1H-NMR titration and have been observed in the case of 4 is a selective receptor for acetate. The theoretical calculation M06/6-311+G(d,p) helped us explain the binding properties observed. The most interesting observation is that this calculated structure is consistent with expected, based on the concept of allylic 1,3-strain (A1,3strain). When chiral caboxylates were studied, urea 1 was the best in discriminating between enantiomers.

Unprecedented Transformation of a Directing Group Generated in Situ and Its Application in the One-Pot Synthesis of 2-Alkenyl Benzonitriles

An unprecedented protocol for the transformation of benzoyl azides into benzonitrile derivatives via iminophosphoranes generated in situ is described. The strategy was successfully applied to the de-novo synthesis of 2-alkenylated benzonitrile derivatives from benzoyl azides through ortho CH activation/alkenylation followed by subsequent rearrangement. The salient features of this protocol involve incorporation of two important functionalities through cyanation and olefination in one pot under mild reaction conditions by using a less expensive Ru catalyst. The mechanism was established by isolating and characterising (using 31PNMR) an intermediate with two ortho functionalities, iminophosphorane and olefin, under specific reaction conditions. Directly functional! Cyanation and olefination was accomplished in one pot from benzoyl azides through an unprecedented directing group transformation. The method generates benzonitriles and can be used for the synthesis of 2-alkenylated benzonitrile derivatives (see scheme).

The challenge of palladium-catalyzed aromatic azidocarbonylation: From mechanistic and catalyst deactivation studies to a highly efficient process

Azidocarbonylation of iodoarenes with CO and NaN3, a novel Heck-type carbonylation reaction, readily occurs in an organic solvent-H 2O biphasic system to furnish aroyl azides at room temperature and 1 atm. The reaction is catalyzed by Xantphos-Pd and exhibits high functional group tolerance. The catalyst deactivation product, [(Xantphos)PdI2], can be reduced in situ with PMHS to Pd(0) to regain catalytic activity. In this way, the catalyst loading has been lowered to 0.2% without any losses in selectivity at nearly 100% conversion to synthesize a series of aroyl azides in 80-90% isolated yield on a gram scale. Alternatively, the ArCON3 product can be used without isolation for further transformations in situ, e.g., to isocyanates, ureas, benzamides, and iminophosphoranes. A detailed experimental and computational study has identified two main reaction pathways for the reaction. For both routes, Ar-I oxidative addition to Pd(0) is the rate-determining step. In the presence of CO in excess, the Ar-I bond is activated by the less electron-rich Pd center of a mixed carbonyl phosphine complex. Under CO-deficient conditions, a slightly lower energy barrier pathway is followed that involves Ar-I oxidative addition to a more reactive carbonyl-free (Xantphos)Pd0 species. Mass transfer in the triphasic liquid-liquid-gas system employed for the reaction plays an important role in the competition between these two reaction channels, uniformly leading to a common aroyl azido intermediate that undergoes exceedingly facile ArCO-N 3 reductive elimination. Safety aspects of the method have been investigated.

Reactions of acyl azides with secondary amines in the presence of copper(II) acetate

The nucleophilic substitution of the azide group in acyl azides for secondary amines in the presence of copper(II) acetate was studied. The formation of the corresponding amides and copper(II) azide in the course of the reaction was observed. The shift of the absorption band of stretching vibrations of the azide group was observed in the IR spectra of the reaction products, which could be explained by the intermediate formation of a complex of acyl azide with the amine complex of copper(II) acetate and by its decomposition to form copper(II) azide and the corresponding amide. A blue-green color of the solution characteristic of copper(II) acetate changed in the course of the reaction to the brown color of a solution of copper(II) azide.

Palladium-catalyzed aromatic azidocarbonylation

Aryl iodides smoothly react with NaN3 and CO in the presence of a Pd/Xantphos catalyst to give aroyl azides (ArCON3) in 75-92 % yield. The reaction occurs under mild reaction conditions (1 atm, 20-50 °C) and exhibits high functional-group tolerance. (Xantphos=9,9-dimethyl-4,5- bis(diphenylphosphino)xanthene)