- A diphenylamine or nucleus method for preparing substituted derivatives
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The invention discloses a preparation method of a diphenylamine or a nucleus-substituted derivative thereof. The method comprises the following steps: in an aprotic polar solvent, performing reaction on an N-acylation aniline or a nucleus-substituted derivative thereof and alkali to form corresponding salts; performing reaction on the salts and a halogeno benzene or a nucleus-substituted derivative thereof to prepare the N-acylation aniline or a nucleus-substituted derivative thereof; and then, preparing the diphenylamine or a nucleus-substituted derivative thereof through de-acylation reaction in the presence of sodium alkoxide. The method has the beneficial effects that three-step reaction of salifying, condensation and de-acylation in one kettle is sequentially carried out, and a separation and purification process of an intermediate product is eliminated, so that the method is short in processes, short in production cycle and high in yield of products.
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Paragraph 0105-0110; 0120-0125
(2020/05/05)
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- Process for manufacturing diphenylamines
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The invention teaches novel process steps for the rapid high yield manufacture of diphenylamines of the formula wherein R1 is selected from hydrogen, alkyl, and aryl; wherein each R2 and R3 is the same or different and each is independently selected from hydrogen, alkyl, alkoxy, aralkyl, dialkylamino, alkylarylamino and substituted or unsubstituted aryl, the substituents on aryl being each independently selected from alkyl (C1-C8), alkoxy (C1-C8), aroxy, aralkoxy and halogen; wherein n and m are each independently an integer from 1 to 5. Diphenylamines are key intermediates for the production of leuco dyes used in pressure-sensitive and heat-sensitive imaging systems. The process in at least one embodiment comprises reacting at elevated temperature an aryl halide with an aromatic amine in an organic solvent and aqueous alkaline solution and optionally in some embodiments, phase-transfer agent, followed by addition of catalytic amounts of bis[tri(t-butylphosphine)]palladium at a suitable temperature to rapidly form diphenylamine.
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Page/Page column 7
(2008/06/13)
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- Process for the manufacture of fluoran compounds
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A process for the preparation of a fluoran compound of the formula STR1 wherein R, R1, R2 and R4 are each independently hydrogen, halogen, lower alkyl or lower alkoxy, R3 is hydrogen, halogen, lower alkyl, lower alkoxy or --NX3 X4, or (R1 and R2) or (R3 and R4) each pair together with the carbon atoms to which they are attached, form a fused benzene nucleus, X1, X2, X3 and X4 are each independently hydrogen, alkyl containing not more than 12 carbon atoms which is unsubstituted or substituted by cyano, halogen, hydroxy, tetrahydrofuryl or lower alkoxy, or are cycloalkyl, aryl or aralkyl or (X1 and X2) or (X3 and X4) are each independently together with the nitrogen to which are attached a 5- or 6-membered heterocyclic ring, and the ring A is unsubstituted or substituted by halogen, nitro, lower alkyl, lower alkylthio, lower alkoxy, lower alkoxycarbonyl, amino, mono-lower alkylamino, di-lower alkylamino or lower alkyl carbonylamino, which process comprises (1) reacting a ketonic acid of the formula STR2 with a substituted phenol derivative of the formula STR3 wherein Z is hydrogen, lower alkyl, formyl or lower alkanoyl and A, R, R1, R2, R3, R4, X1 and X2 have the given meanings, (2) adding the reaction product to an aqueous-organic liquor containing a non-polar organic solvent and a base at a temperature of 50° to 90° C., (3) separating the organic phase and (4) removing the organic solvent to obtain the fluoran of the formula (1).
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- Process for producing diphenylamines or N,N'-diphenyl-phenylenediamines
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Diphenylamines or N,N'-diphenyl-phenylenediamines can be obtained by heat-reacting an aniline or a phenylenediamine with preferably an excess of a phenol in an amount of 4 to 20 moles per mole of the aniline or phenylenediamine in the presence of a hydrogen transfer catalyst and a cyclohexanone corresponding to said phenol. The excess phenol used in the reaction undergoes reduction in the reaction system to form a cyclohexanone, which in turn reacts with the aniline or phenylenediamine to form a Schiff base and is thus consumed. The Schiff base forms the intended product by means of a dehydrogenation reaction, and the hydrogen evolved at this time reduces the phenol to form a cyclohexanone. The phenol present in excess thus becomes in the system a solvent, a starting material for the cyclohexanone, and an acceptor of the hydrogen that forms as a by-product at the time of formation of the intended product. Hence, it becomes possible to obtain the intended product at a high selectivity from the anilines and phenylenediamines. The process of this invention is an advantageous process for the industrial production of especially the nuclearly substituted diphenylamines.
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