- On the Kolbe-Schmitt synthesis of pharmacologically useful salicylates: Carboxylation of 2,4-di-t-butylphenol and identification and reduction of the formation of 2,2'-dihydroxy-3,3',5,5'-tetra-t- butylbiphenyl in the synthesis of 3,5-di-t-butylsalicylic acid
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The initial yield of 3,5-di-t-butylsalicylic acid obtained via Kolbe-Schmitt carboxylation of the potassium salt of 2,4-di-t-butylphenol was 1% and was accompanied by a 65% yield of 2,2'-dihydroxy-3,3',5,5'-tetra-t-butylbiphenyl, a dimer of the 2,4-di-t-butylphenol formed by ortho coupling of phenoxide radicals. Formation of this dimer was decreased to 8%, and the yield of 3,5-di-t-butylsalicylic acid was increased to 68% by optimizing reaction time and temperature and decreasing the amount of oxygen present during carboxylation. This modification of the Kolbe-Schmitt reaction conditions may be generally helpful in the synthesis of all pharmacologically useful salicylates.
- Chidambaram,Sorenson
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- Metal complex-(3,5-di-tert-butyl salicylic acid) method for the preparation of
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The invention provides a preparation method for metal complex-(3,5- di-tert-butyl salicylic acid). The preparation method comprises the steps of dissolving 3,5- di-tert-butyl salicylic acid in alkali metal hydroxide liquor, and synthesizing the metal complex-(3,5- di-tert-butyl salicylic acid) by adopting different mixing ways with metal salt liquor at 60-70 DEG C, wherein the complex-(3,5- di-tert-butyl salicylic acid) can be used as an antistatic agent and a charge control agent for powdered ink. The invention further provides a method for preparing 3,5- di-tert-butyl salicylic acid by taking the methyl salicylate as the material through Friedel-Craft reaction and hydrolysis reaction of ester.
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- COMPOUNDS USEFUL FOR THE TREATMENT OF METABOLIC DISORDERS AND SYNTHESIS OF THE SAME
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The present invention provides compounds of Formula (I): wherein variables X, Y, Z and R1 are as described herein. Some of the compounds described herein are glutamate dehydrogenase activators. The invention is also directed to pharmaceutical compositions comprising these compounds, uses of these compounds and compositions in the treatment of metabolic disorders as well as synthesis of the compounds.
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- Urotropin synthesis of 3,5-di-tert-butylsalicylic acid derivatives
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The stability of 3,5-di-tert-butylsalicylic aldehyde against oxidation is due to autoinhibiting of the chain process. However its oxidation into 3,5-di-tert-butylsalicylic acid was performed at the use of acetyl protection of the hydroxy group. In reaction of 6-bromo-2,4-di-tert-butylphenol with urotropin the formation was discovered of 3,5-di-tert-butylsalicylic acid, its nitrile and amide.
- Vol'eva,Belostotskaya,Komissarova,Kurkovskaya,Pleshakova,Prokofeva
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p. 1488 - 1491
(2008/09/16)
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- Convenient and efficient method for the obtainment of ketones from highly hindered aromatic N,N-dimethyl-amides
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A simple and efficient procedure to synthesize highly hindered alkyl aryl ketones that involves the coupling of N,N-dimethyl-3,5-di-tert-butylsalicylamide with organolithium compounds is described. Mild reaction conditions and good to excellent yields of the products are the noteworthy advantages of the procedure. Copyright Taylor & Francis Group, LLC.
- Jimenez, Claudio A.,Belmar, Julio B.
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p. 2391 - 2397
(2008/02/10)
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- PROCESS FOR PRODUCTION OF HYDROXYBENZOIC ACIDS
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The present invention provides A method for producing a hydroxybenzoic acid compound comprising, preparing an alkali metal salt of a phenol compound from the phenol compound, and reacting the alkali metal salt of the phenol compound with carbon dioxide, wherein the step of preparing the alkali metal salt of the phenol compound from the phenol compound comprises the steps of:a) reacting an alkali metal alkoxide with an excess amount of the phenol compound, which is in excess of the alkali metal alkoxide, to give the alkali metal salt of the phenol compound, andb) distilling away the generated alcohol from the reaction simultaneously with carrying out step a). The method of the present invention makes it possible to produce hydroxybenzoic acid compound in high yield without using aprotic polar organic solvent.
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Page/Page column 7-8
(2010/02/14)
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- PROCESS FOR PRODUCTION OF HYDROXYBENZOIC ACIDS
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The present invention provides a method for producing a hydroxybenzoic acid compound comprising, dehydrating a phenol compound and an alkaline metal compound to form the alkaline metal salt of the phenol compound and reacting the alkaline metal salt and carbon dioxide, wherein the dehydrating step is conducted by reacting the alkaline metal compound with an excess amount of the phenol compound at a temperature of 160°C or above. According to the method of the present invention, the hydroxybenzoic acid compound can be obtained by simple steps with low cost without using an expensive aprotic polar organic solvent. The provided method can produce highly pure hydroxybenzoic acid compound comprising little by-products in high yield.
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- Synthesis of highly hindered polyanionic chelating ligands
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Practical and efficient protocols to obtain highly hindered polyanionic chelating ligands based on bis-(3,5-di-tert-butyl-2-hydroxybenzamido) compounds are reported here. N-3,5-di-tert-Butylsalicyloyloxysuccinimide was treated with aliphatic diamines to form aliphatic hydrocarbon-linked bis-amides 4a-4g. Aromatic diamines required more powerful electrophile, thus the corresponding benzylated acid chloride was used to form aromatic hydrocarbon-linked bis-amides 8a-8d. The yields ranged from good to very good and showed that choosing the right acylating agent is a key point in this synthesis. All the compounds were characterized by elemental analysis, IR, MS and NMR.
- Jiménez, Claudio A.,Belmar, Julio B.
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p. 3933 - 3938
(2007/10/03)
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- Charge control agent, manufacturing process thereof, charge control resin particles and toner for developing electrostatic images
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Charge control agent whose active ingredient is a zinc compound of an alkylsalicylic acid derivative, the compound being a zincified alkylsalicylic acid derivative which is an alkylphenol derivative having a carboxyl group introduced thereto; Toner for developing electrostatic images, comprising said charge control agent, a coloring agent and a binder resin for toner; Charge control resin particles comprising solidified milled particles of a thermally kneaded mixture of at least said charge control agent and a resin.
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- Process for preparing hydroxybenzoic acids
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A process for preparing a hydroxybenzoic acid is herein disclosed which comprises reacting a phenol with an alkali metal compound by the use of an aprotic polar organic solvent as a reaction solvent to form an alkali metal salt of the phenol, and then reacting this alkali metal salt with carbon dioxide to obtain a hydroxybenzoic acid, said process comprising the step of carrying out the reaction under conditions that a molar ratio of the phenol to the total of the alkali metal compound and the aprotic polar organic solvent is larger than 1. Furthermore, the process may contain the steps of precipitating crystals from the reaction solution, separating the solid from the solution to obtain a wet alkali metal salt of the hydroxybenzoic acid, dissolving the wet alkali metal salt in water, and precipitating crystals from the solution by acidification to obtain the hydroxybenzoic acid.
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Page column 8
(2010/02/05)
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- A practical route to regiospecifically substituted (R)- and (S)-oxazolylphenols
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New, diversely substituted phenolic oxazolines 14a-d and 15a-d were prepared by two complementary routes A and B, starting from salicylic derivatives 4-7 and various enantiomerically pure 1,2-amino alcohols 13a-d. In route A, the 1,2amino alcohols 13a-d were directly condensed with the salicylic acids 5 and 7, using the Appel reaction, whereas in route B the amino alcohols 13b-d were treated with the 2-hydroxybenzonitriles 4 and 6, under Witte-Seeliger conditions. The latter route was advantageous for L-valinol 13b and L-tert-leucinol 13c, while route A was the method of choice for the new, sterically demanding amino alcohol 13a, prepared from D- and L-serine. The nitro group in the salicylic derivatives 5 and 6 was introduced by means of a regiospecific ipso substitution of a tert-butyl group by nitric acid. The structure of the nitro product 5 was unambiguously assigned by NOE spectroscopy on the basis of the recently developed DPFGSE-ROE pulse sequence.
- Scheurer, Andreas,Mosset, Paul,Bauer, Walter,Saalfrank, Rolf W.
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p. 3067 - 3074
(2007/10/03)
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- Salicylic acid derivatives
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The heat-sensitive recording material disclosed comprises a colorless or pale colored dyestuff precursor, one or more salicylic acid derivative of the formula (1) or metal salt of the derivative and an aliphatic amide compound having 18?60 carbon atoms in molecular structure, and is excellent in thermal response and preservation stability of white portions and images. STR1 wherein X1 and X2 are a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aralkyl group or an aryl group, Y1 and Y2 are an oxygen atom or a sulfur atom, R1 is a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R2 is an alkyl group, an alkenyl group, an aralkyl group or an aryl group.
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