67097-77-2

Upstream product

• 42540-91-0 6-nitro-1,2-benzisoxazole-3-carboxylate 
• 643-43-6 (2,4-dinitro-phenyl)-acetic acid 
• 58605-12-2 (2,4-dinitro-phenyl)-acetic acid methyl ester 
• 5453-86-1 methyl 6-nitro-1,2-benzisoxazole-3-carboxylate 
• 28691-50-1 6-Nitro-benzo[d]isoxazole-3-carboxylic acid 

Relevant academic research and scientific papers

Silica gel supported phosphonium salts as micellar and phase transfer catalysts

Phosphonium salts immobilized on silica gel have been found to be both micellar and phase-transfer catalysts. They are able to exchange their parent anions with the anions present in an aqueous solution and promote, in catalytic amounts, the decarboxylation of 6-nitrobenzisoxazole-3-carboxylate to give 2-cyano-5-nitrophenolate, a test for micellar catalysis.

Decarboxylation of 6-Nitrobenzisoxazole-3-carboxylate Catalyzed by Ammonium Bilayer Membranes. A Comparison of the Catalytic Behavior of Micelles, Bilayer Membranes, and Other Aqueous Aggregates

Decarboxylation of 6-nitrobenzisoxazole-3-carboxylate was studied at 5-50 deg C in water in the presence of CTAB micelles, dialkylammonium (2CnN+2C1) bilayer membranes, and trioctylmethylammonium (TMAC) aggregates.These aqueous aggregates possess totally different morphologies with each other, but their general rate acceleration effects increased simply with increasing local hydrophobicities: CTAB +2C1 +2C1 (n = 12, 14, 16, 18) invariably showed inflections at or near the respective phase transition temperature (Tc).The activation energy data suggest that the membrane catalyst is governed mainly by the hydrophobicity and fluidity (or rather rigidity) at temperatures above and below Tc, respectively.

Vesicular catalysis of the decarboxylation of 6-nitrobenzisoxazole-3- carboxylate. The effects of sugars, long-tailed sugars, cholesterol and alcohol additives

The effects of the addition of sugars, long-tailed n-alkyl pyranosides, n-alkyl glycerol ethers and n-alcohols on the properties of di-n- hexadecyldimethylammonium bromide (DHAB) vesicles have been studied. Properties that were examined include the stability, morphology, phase of the tails, and catalytic rate acceleration of the unimolecular decarboxylation of the 6-nitrobenzisoxazole-3-carboxylate anion (6-NBIC). The kinetic data were analyzed on the basis of the pseudophase model and show a rate acceleration of a factor of about 1000 relative to the reaction in water. Upon addition of most additives an inhibiting effect on the decarboxylation reaction of 6-NBIC is observed relative to the reaction in vesicles without any additive. The largest inhibition was observed in the case of cholesterol. Contrastingly, n-dodecyl-β-maltoside (in the spherical vesicle region) and trehalose accelerate the reaction. The activation parameters show that the most significant contribution to the Gibbs energy of activation is the enthalpic factor, with a partly compensating entropic contribution. Copyright

Synthesis and Catalytic Properties of Hydrophobically Modified Poly(alkylmethyldiallylammonium bromides)

A series of hydrophobically modified homo- and copolymers of the poly(alkylmethyldiallylammonium bromide) type has been prepared by free-radical cyclo(co)polymerization of alkylmethyldiallylammonium bromide monomers in aqueous solution.Depending on the length of the alkyl side chain (varied between C1 and C12) and the conformational freedom of the polymeric main chain, polysoap behavior was found as indicated by the hypsochromic shift of the long-wavelength absorption band of Methyl Orange, noncovalently bound to the macromolecule.The formation of a compact coil results in the presence of hydrophobic microdomains.Polysoap formation, akin to intramolecular micellization, is also revealed by appreciable catalytic effects on the unimolecular decarboxylation of 6-nitrobenzisoxazole-3-carboxylate at pH 11.3 and 30 degC.

Effect of Alkyl Chain Stiffness and Branching on the Properties of Micelles Formed from 1-Methyl-4-(C12-alkyl)pyridinium Iodide Surfactants

This paper describes a study of the micellization of four 1-methyl-4-(C12-alkyl)pyridinium iodide surfactants in which C12-alkyl is n-dodecyl (1), 9,9-dimethyldecyl (2), 1-methylundecyl (3), and 1-dodec-5-ynyl (4).Alkyl chain branching (1-3) exerts only a minor effect on the stability of the micelles (as indicated by the cmc's) and on the properties of the micellar surface (as indicated by counterion binding, charge-transfer absorption bands, and kinetic data for decarboxylation of micellar-bound 6-nitrobenzisoxazole-3-carboxylate).By contrast, chain packing is substantially affected as revealed by large differences in the surfactant concentration (second cmc) for transition of spherical into rodlike micelles.The latter effects are rationalized in terms of the packing parameter P, introduced by Israelachvili.The alkyl chain in surfactant 4 is more stiff and somewhat less hydrophobic, leading to a higher cmc and modified behavior of the micelles toward the kinetic probe.

Supramolecular kinetic effects by pillararenes: The synergism between spatiotemporal and preorganization concepts in decarboxylation reactions

A study about spontaneous decarboxylation reactions of 3-carboxy-1,2-benzisoxazole (CBI) nitrated derivatives (6-NitroCBI and 5,6-DinitroCBI) compared with supramolecular kinetic effects promoted by two cationic pillararenes (P5A and P6A) has been carried

Effects of medium on decarboxylation kinetics: 3-Carboxybenzisoxazoles and their potential use as environmental probes in biochemistry

The decarboxylation rate of the tetramethylguanidinium salt of 3- carboxy-6-nitrobenzisoxazole in 24 pure solvents and 36 dimethyl sulfoxide binary mixtures with diglyme, acetonitrile, benzene, dichloromethane, chloroform, and methanol was analyzed in the light of the SPP, SA, and SB pure solvent scales. The results allow one to rationalize the high sensitivity of this kinetics to the reaction medium and to assess the potential use of this compound as a probe in biochemical environments. The natural environment for comparison of this kinetics was found to be the gas phase rather than the aqueous medium. In the latter, the process is much faster owing to such high polarity, which, however, is strongly diminished by the high acidity of the medium. Based on our calculations, the rate constant for the decarboxylation kinetics in the gas phase must be in the region of 2 x 10-10 s-1 (i.e., 3 orders of magnitude smaller than in water).

Cyclisation and decarboxylation in zwitterionic micelles: effects of head group structure

The spontaneous decrboxylation of 6-nitrobenzisoxazole-3-carboxylate ion is strongly catalysed by micelles of zwitterionic surfactants, viz., sulfobetaines +R2(CH2)3SO3-, R = Me, Pr and C16H33N+Me2(CH2)3SO3-> and amine oxides (C14H29N+R2O-, R =Me,Pr), with rates enhanced by factors of up to 1800.These micelles and those of the corresponding carboxybetaines are more effective catalysts than those of the corresponding cationic surfactants.In all cases a change from Me to Pr at the head group speeds reaction by factors of ca. 5-8 for the sulfobetaines and amine oxides and ca. 14 for the cationic surfactants.Cyclizations of the o-3-halopropyloxyphenoxide ions (halogen = Br,I), which are intramolecular SN2 reactions, are modestly micellar catalysed, but structural effects on the micellar catalysis by cationic and betaine surfactants are in the same sequence, as for decarboxylation.

EFFECT OF MULTIPLE FIELD ASSISTANCE WITH REVERSED MICELLES ON THE DECARBOXYLATION OF 6-NITRO-1,2-BENZISOXAZOLE-3-CARBOXYLATE.

Decarboxylation reaction of 6-nitro-1,2-benzisoxazole-3-carboxylate in cationic and anionic reversed micelles has been investigated with particular attention to the microenvironmental effect, such as microviscosity, micropolarity, and microactivity, in the specific and restricted reaction field as provided by reversed micelles. In 0. 20 M CTAC/0. 32 M H//2O/CHCl//3 reversed micelles, the reaction was accelerated about 1300-fold compared with that in bulk aqueous solution. Of various surfactant aggregate systems such as aqueous micelle, bilayer, and reversed micelle, the cationic reversed micelle could provide the most effective reaction field for the present decarboxylation reaction. This reaction is never accelerated in an anionic aqueous micelle. However, in the anionic AOT reversed micelle, the reaction was apparently accelerated by both lowering the micropolarity and increasing the microviscosity around the substrate.

Oil-in-Water Microemulsions as Reaction Media

Fluorescent spectral shifts suggest that oil-in-water microemulsions of cetyltrimethylammonium bromide (CTABr), an alcohol, and a hydrocarbon have polarities, as measured by Kosower's Z scale, similar to those of cationic micelles, and consistently the ra