73607-73-5

Upstream product

• 119-65-3 isoquinoline 
• 56-23-5 tetrachloromethane 
• 1785-95-1 2-benzoyl-1,3-indanedione 
• 859773-30-1 3,4-di-tert-butyl-1,1,6,6-tetraphenyl-hexa-1,2,4,5-tetraene 
• 1125-80-0 3-methylisoquinoline 
• 85-44-9 phthalic anhydride 
• 5698-59-9 benzo[c]thiophene-1,3-dione 
• 109-72-8 n-butyllithium 
• 60-29-7 diethyl ether 
• 88-67-5 2-Iodobenzoic acid 
• 5022-29-7 N-ethylphthalimide 
• 1914-20-1 N-methoxyphthalimide 
• 91-20-3 naphthalene 
• 95-47-6 o-xylene 

Downstream Products

• 101875-03-0 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N-pyrimidin-2-yl benzenesulfonamide 
• 108536-58-9 4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N-(4-methylpyrimidin-2-yl)benzenesulfonamide 
• 88063-41-6 N-(4,6-dimethylpyrimidin-2-yl)-4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)benzenesulfonamide 
• 5211-78-9 2-carboxyphenyl 2-hydroxy-4-methylphenylmethanone 
• 30982-52-6 3’,6’-dimethylfluorescein 
• 95026-07-6 phthalic acid bis-(2-methoxy-phenyl ester) 
• 6307-10-4 4-nitrophthalanilic acid 
• 5166-59-6 phthalic acid bis-(4-phenyl-phenacyl ester) 
• 145179-25-5 phthalic acid ; compound with ethylenediamine 
• 4870-16-0 N-anilinophthalimide 
• 7554-84-9 β-naptalam 
• 114192-16-4 2-(2-hydroxy-4,5-dimethyl-benzoyl)-benzoic acid 
• 50281-82-8 phthalic acid bis-(2-allyloxy-ethyl ester) 
• 42473-87-0 2-(4-ethoxyphenyl)isoindoline-1,3-dione 

Relevant academic research and scientific papers

Kinetics and mechanism of intramolecular carboxylic acid participation in the hydrolysis of N-methoxyphthalamic acid

The rate of formation and disappearance of phthalic anhydride (PAn) intermediate in the aqueous cleavage of N-methoxyphthalamic acid (NMPA) under acidic pH was studied spectrophotometrically in mixed CH3CN-H2O solvents. The rate of formation of PAn from NMPA is almost independent of the change in acetonitrile content from 20 to 70% v/v in mixed aqueous solvents. The rate constants for the formation of PAn from NMPA are ～ 10-fold smaller than the corresponding rate constants for the formation of PAn from o-carboxybenzohydroxamic acid (OCBA). These observations are ascribed to the consequence of the occurrence of slightly different mechanisms in these reactions.

Preventing false-negatives in the in vitro skin sensitization testing of acid anhydrides using interleukin-8 release assays

In vitro safety tests may be used as replacements for animal tests owing to their accuracy and high-throughput performance. However, several in vitro skin sensitization tests produce false-negative results such as acid anhydride. Here, we investigated the relationship between false-negative results of acid anhydride and its hydrolysis by aqueous vehicle. Differences in the pattern of hydrolysis for phthalic anhydride (PAH) due to addition of 1 drop of stock solution of PAH in liquid paraffin (LP) dispersion medium and PAH in DMSO were analyzed in a cell-free system. The results showed that use of LP dispersion medium stabilized the concentration of PAH in water over 5 min by sustained-release, although almost all PAH converted to phthalic acid in water within 5 min using DMSO. Additionally, treatment of THP-1 cells with PAH and phthalic acid using LP dispersion medium for 5 min resulted in a 32-fold increase in IL-8 release for PAH as compared with that in the vehicle control. In contrast, for PAH using aqueous vehicle and phthalic acid using LP dispersion medium, there were no significant increases in IL-8 release. Similarly, using LP dispersion medium, trimellitic anhydride significantly increased IL-8 release was observed.

Proton Inventory of Phthalic Anhydride Hydrolysis. Comments on Analysis of Proton-Inventory Data

The spontaneous hydrolysis of phthalic anhydride exhibits rate constants kn in mixtures of deuterium oxide (atom fraction n of deuterium) and protium oxide which are best described by the equation 106kn = 1058(1 - n + 0.69)3(1 - n + 1.33n) s-1.This result suggests a hydronium ion and a gem-diol-like proton as structural features in the rate-limiting transition-state structure.Two such structures, 3 and 4, are proposed as consistent with this result and previous mechanistic studies.A thorough analysis of nonlinear equations used in proton inventory studies is presented and the criteria for evaluating a "good fit" are discussed.

Oxidative ring cleavage of 2,3-dihydrophthalazine-1,4-dione in aqueous and non-aqueous solutions: Electrochemical and kinetic studies

Electrochemical oxidation of 2,3-dihydrophthalazine-1,4-dione (DHP) has been investigated in aqueous and some amphiprotic and aprotic non-aqueous solvents by cyclic voltammetric and controlled-potential coulometric techniques. Our data shows that electroc

Kinetics and mechanism of the general base-catalyzed hydrolysis of N-hydroxyphthalimide

The kinetics and mechanism of hydrolysis of N-hydroxyphthalimide in the presence of various buffers (dichloroacetic acid, chloroacetic acid, glycine, sodium formate, sodium acetate, N-(2-morpholinoethane)sulfonic acid, and tris(hydroxymethyl)aminomethane) were studied at 50 C and an ionic strength of 1.0 M. The second-order rate constants k b for the buffer-catalyzed hydrolysis of N-hydroxyphthalimide were found to conform to the Bronsted equation logk b = C + β pK a. A plot of pK a versus k b for the data obtained in the buffers and H2O (covering a pK a range of -1.74 to 8.33) was constructed, and the data were fitted with a straight line that had a slope (β) of 0.29 ± 0.05 and an intercept (C) of -5.19 ± 0.20.

Oxidative Degradation of Azo Dyes in Aqueous Solution by Water-Soluble Iron Porphyrin Catalyst

Textile and food industries produce a significant volume of effluents containing azo dyes and other pollutants. These effluents are serious environmental threats, and new methods for their treatment and for the degradation of azo dyes are thus attracting much attention. The current study deals with the oxidative degradation of azo dyes by meso-tetrakis(1-methylpyridinium-4-yl)prophyrinatoiron(III), [FeIII(tmpyp)], and meta-chloroperoxy benzoic acid (m-CPBA) in aqueous solution at room temperature. The catalytic degradation of azo dyes was investigated by using rapid-scan stopped-flow spectrophotometry as a function of solution pH, [catalyst], [m-CPBA], [dye] and [surfactants]. To obtain mechanistic insight, the reaction between [FeIII(tmpyp)] and m-CPBA was also studied in aqueous solution in absence of azo dyes. Spectral analyses and kinetic data show that [FeIII(tmpyp)] is transformed into the transient intermediate [FeIV(O)(tmpyp)].+ (a compound I analog) within 20–30 ms followed by the formation of relatively stable [FeIV(O)(tmpyp)] (a compound II analog). Batch experiments reveal that the dye degradation rate is influenced by the solution pH and the concentrations of [FeIII(tmpyp)], m-CPBA, dye, and surfactants. On the basis of the kinetic and spectroscopic data, a mechanistic scheme for the dye degradation reaction and a steady-state rate equation are proposed. The products resulting from oxidative degradation of the azo dye amaranth have been analyzed by HPLC-UV-HRMS.

Employment of immobilised lipase from Candida rugosa for the bioremediation of waters polluted by dimethylphthalate, as a model of endocrine disruptors

A planar bioreactor, equipped with a polypropylene membrane on which a lipase was immobilised, has been employed in a bioremediation process involving water polluted by dimethylphthalate (DMP), a model for a class of endocrine disruptors. The dependence of enzyme activity on pH, temperature and DMP concentration has been characterised under isothermal conditions, whereas the kinetics parameters have been studied under non-isothermal conditions. The following sequence was found for the values of lipase affinity, Km, towards the DMP: Kmfree m, non-isothimm m, isothimm. A comparison of the results obtained under isothermal and non-isothermal conditions indicated that there was an advantage in using non-isothermal bioreactors in the environmental field. These advantages in particular resulted in: (i) an increase in the enzyme activity proportional to the applied transmembrane temperature difference and (ii) a reduction in the bioremediation times and, consequently, the process costs. The advantages in using bioremediation processes in the place of classical membrane processes, such as ultrafiltration or reverse osmosis, are also discussed.

Selective Synthesis of Aryl Nitriles and 3-Imino-1-oxoisoindolines via Nickel-Promoted C(sp2)-H Cyanations

An efficient nickel-promoted selective monocyanation of benzamides with TMSCN via 8-aminoquinoline directed ortho C-H activation has been developed. Varieties of functionalized ortho-cyanated (hetero)aryl nitriles can be selectively synthesized in moderate to good yields. These cyanation products can be easily transformed into various 3-imino-1-oxoisoindolines in a one-pot procedure. The mild reaction conditions, use of cheap and commercially available reagents, wide functional group tolerance, and operational convenience make this protocol practical to the synthetic community.

Structure effects of amphiphilic and non-amphiphilic quaternary ammonium salts on photodegradation of Alizarin Red-S catalyzed by titanium dioxide

The role of surfactants such as single- and double-tailed tetraalkylammonium bromide and various non-amphiphilic tetraalkylammonium salts was investigated on the TiO2 photocatalyzed degradation of 3,4-dihydroxy-9,10-dioxo-2-anthracenesulfonic acid sodium salt (Alizarin Red-S, ARS) in an air-equilibrated alkaline medium under UV light irradiation. Absorption spectral analysis showed that the photodegradation efficiency of the dye was significantly enhanced by the addition of cationic surfactants. Two interesting findings emerged from this study: ARS was almost completely degraded at surfactant concentrations close to 1 mM (values well above the cmc in the experimental conditions); moreover, on increasing the surfactant concentration, the photocatalytic reaction became less and less efficient and significantly dependent on the surfactant headgroup size. The presence of a maximum of efficiency depending on the surfactant concentration was due to the combination of catalytic and inhibiting processes. The first one likely depended on the ability of the surfactant to improve the ARS approach to the semiconductor through the formation of cationic bilayers on the TiO2 particles; this effect made the ARS more easily oxidized by TiO2. This catalytic action of the surfactant was opposed by the increase of the micellar aggregate number in the aqueous bulk, which competes with the TiO2 sites in associating to the dye. This was supported by the results obtained with the non-amphiphilic alkylammonium bromide. In this case a higher amount of salt must be added to reach the same maximum efficiency of ARS photooxidation. This is due to the lower capability of neutralization of these salts for both the ARS and the TiO2 surface; the inhibiting effect was not evidenced anymore.

Unexpected rate enhancement in the intramolecular carboxylic Acid-catalyzed cleavage of o-carboxybenzohydroxamic acid

Phthalic anhydride was detected spectrophotometrically in the hydrolysis of o-carboxybenzohydroxamic acid (OCBA) in CH3CN-H2O solvent containing 0.03 mol dm-3 HCl. Pseudo-first-order rate constants (K1) for hydrolysis of OCBA are almost independent of the change in CH3CN content from 10 to 80% (v/v) in mixed aqueous solvents. The rate constants k1 are more than 10-fold larger than the corresponding rate constants for hydrolysis of phthalamic acid. These observations are explained in terms of a mechanism slightly different from the mechanism for hydrolysis of phthalamic acid. The activation parameters, ΔH * and ΔS *, are not affected appreciably by an increase in CH3CN content from 10 to 80% in mixed aqueous solvents.