2169-87-1Relevant articles and documents
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Schoenberg,Fayez
, p. 104 (1958)
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Hydrolysis of 1,8- and 2,3-naphthalic anhydrides and the mechanism of cyclization of 1,8-naphthalic acid in aqueous solutions
Barros, Teresa C.,Yunes, Santiago,Menegon, Guilherme,Nome, Faruk,Chaimovich, Hernan,Politi, Mario J.,Dias, Luis G.,Cuccovia, Iolanda M.
, p. 2342 - 2350 (2001)
Naphthalene-1,8-dicarboxylic acid, 1,8-Acid, cyclizes spontaneously in acidic aqueous solution to naphthalene-1,8-dicarboxylic anhydride, 1,8-An, and here we Present an ab initio study of the reaction pathway. The effect of pH on the hydrolysis of 1,8-An was analysed and compared with the hydrolysis of naphthalene-2,3-dicarboxylic anhydride, 2,3-An, to naphthalene-2,3-dicarboxylic acid, 2,3-Acid. The values of the pKa's of 1,8-Acid and 2,3-Acid were ca. 3.5 and 3.0, for monoanion formation, pKa1, and 5.5 and 5.0 for dianion formation, pKa2, respectively. Fluorimetric titration demonstrated that the diprotonated 2,3-Acid. AH2, was further protonated to yield AH3+. The pH-rate constant profile for 2,3-An hydrolysis showed a water reaction between pH's 1.0 and 6.0 and a base catalysed hydrolysis above pH 7.0. Under no condition was 2,3-An formed from 2,3-Acid. The pH dependent decomposition kinetics of 1,8-An is complex and, below pH 6.0, the pH-rate constant profile was fitted by assuming that both AH2 and AH3+ are in equilibrium with 1,8-An. The values of the equilibrium constants for 1,8-An formation from AH2 and AH3+ were ca. 4 and 100 in dilute and concentrated acid, respectively. Ab initio calculations for a possible reaction pathway connecting the undissociated 1,8-Acid to 1,8-An show a transition state where an intramolecular proton transfer is concerted with oxygen alignment towards the carbonyl centre. The planar intermediate is then dehydrated yielding a complex between water and 1,8-An.
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Scott
, p. 6332 (1953)
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New Derivatizing Agents for Amino Acids and Peptides. 1. Facile Synthesis of N-Substituted 1-Cyanobenzisoindoles and Their Spectroscopic Properties
Carlson, R. G.,Srinivasachar, K.,Givens, R. S.,Matuszewski, B. K.
, p. 3978 - 3983 (1986)
2,3-Naphthalenedicarboxaldehyde (NDA) is shown to be a very useful reagent for the derivatization of primary amines, amino acids, and small peptides.The reaction of these amino compounds with NDA and cyanide ion produces highly fluorescent 2-substituted 1-cyanobenzisoindoles that are relatively stable.The physical and fluorescent properties of a variety of 1,2-disubstituted benzisoindoles are presented.
Preparation method of 2,3-naphthalic acid
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, (2017/07/23)
The invention discloses a preparation method of 2,3-naphthalic acid, belonging to the technical field of preparation of organic compounds used as medical and liquid crystal intermediates. According to the preparation method, o-phthalaldehyde is used as a raw material, and through performing acetalation reaction, reducing reaction, hydrolysis reaction, cycloaddition reaction, dehydration reaction and hydrolysis reaction in sequence, finally the 2,3-naphthalic acid is prepared. The preparation method optimizes the reaction steps and conditions and has the advantages of reasonable synthetic route, high purity and yield of product, low production cost, low pollution, easy industrialization and the like.
Rapid chemoselective deprotection of benzyl esters by nickel boride
Khurana, Jitender M.,Arora, Reema
experimental part, p. 1127 - 1130 (2009/12/03)
Benzyl esters of a variety of acids can be chemoselectively cleaved on treatment with nickel boride in methanol at ambient temperature to give the parent carboxylic acids in high yields. Other protecting functionalities such as methyl, ethyl, tert-butyl, and trityl esters as well as benzyl ethers, tert-butyl ethers, and Nbenzylamides are unaffected under these conditions. Georg Thieme Verlag Stuttgart.
