- Reductive acylation of nitroarenes to anilides by sodium sulfite in carboxylic acids
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A facile and efficient reductive acylation of aromatic nitro compounds to corresponding anilides using a sodium sulfite-carboxylic acid system for the first time has been reported. The sodium sulfite reagent provides the colorless reductant in combination with stoichiometric amounts of carboxylic acid and enables the formation of anilides from nitroarenes without any additives in good to excellent yields with high purities and simple work-up. Furthermore, this protocol provides a novel and complementary access to some industrially important chemicals in kilogram scale under mild conditions.
- Ghaffarzadeh, Mohammad,Akhavan, Pegah
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- Spectrophotometric and Titrimetric Determination of Carboxylic Acid Anhydrides
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Two redox methods are described for the determination of carboxylic acid anhydrides involving reaction with either an excess of 4-aminophenol or a measured but excessive amount of sulfanilamide and photometric titration of N-acyl-4-aminophenol with 2-iodylbenzoate by measuring the absorbance of orange-red product at 444 nm or the residual amount of sulfanilamide is determined by titration with chloramine-T in the presence of acidified potassium bromide using methyl red as visual indicator.Mixtures of certain anhydrides have also been analyzed by the 2-iodylbenzoate method.The methods are rapid, precise, and accurate.No correlation is needed if carboxylic and mineral acids are also present.Carboxylic acid chlorides also react quantitatively.
- Verma, Krishna K.,Tyagi, Pramila
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- 2-Propanol derivatives as corrosion inhibitors
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New composition comprises a functional fluid in contact with ferrous metal and a corrosion inhibiting amount of at least one compound of formula (I) STR1 or a derivative thereof in which R1, R2 and R3 are, independently, hydrogen, a C1 -C15 straight or branched chain alkyl residue, a C5 -C12 cycloalkyl residue, a C6 -C15 aryl residue or C7 -C12 alkaryl residue, and R4 and R5 are, independently, hydrogen, 2-hydroxyethyl or 2-hydroxypropyl with the provisos that (a) R4 and R5 are not simultaneously hydrogen, (b) when R4 and R5 are each --CH2 --CH2 --OH, R1 and R2 are not simultaneously hydrogen and R3 is not a pentyl residue and (c) that polyalkylene and phenol or polycarboxylic ester co-additives are absent; as well as salts thereof. Some of the compounds of formula I are new.
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- Corrosion inhibiting composition
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A composition, in contact with a corrodable metal surface, which composition comprises: (a) an aqueous-based or oil-based system; and (b) as inhibitor for protecting the metal surface against corrosion, at least one compound having the formula I: STR1 as well as salts or partial esters thereof wherein: n is 0 or an integer ranging from 1 to 20, R is a straight or branched chain C4 -C30 alkyl group, optionally interrupted by one, two or three oxygen atoms or substituted by one, two or three hydroxy groups, a C5 -C12 cycloalkyl group, a C6 -C10 aryl group optionally substituted by one, two or three C1 -C12 alkyl groups, or a C7 -C13 aralkyl group which is optionally substituted by a hydroxyl group; R1 is H or a straight- or branched chain C1 -C4 alkyl group; R2 is H, a straight or branched chain C1 -C4 alkyl group or CO2 H; R3 is H, a straight or branched chain C1 -C4 alkyl group, --CH2 CO2 H or --CH2 CH2 CO2 H; R4 is H, a straight or branched chain C1 -C4 alkyl group or CO2 H; R5 is H, a straight or branched chain C1 -C4 alkyl group, CH2 CO2 H or CH2 CH2 CO2 H; provided that at least one group R4 must be CO2 H, with the provisio, that compositions comprising an oil-based system and a compound having the formula STR2 wherein R, R1 and R2 are hydrogen or alkyl radicals, having a total from 10 to 38 C-atoms, are excluded.
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- Triazole-organodithiophosphate reaction product additives for functional fluids
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New reaction products, useful as additives for functional fluids, are obtained by reacting, at elevated temperature, (A) a triazole having the formula IA or IB: STR1 wherein R7 is hydrogen or a C1 -C20 alkyl residue; R8 and R9 are the same or different and each is C1 -C20 alkyl, C3 -C20 alkenyl, C5 -C12 cycloalkyl, C7 -C13 aralkyl, C6 -C10 aryl or R8 and R9, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic residue or R8 and R9 is each a residue of formula: wherein X is O, S or N(R12), R12 is hydrogen or C1 -C20 alkyl, "alkylene" is a C1 -C12 alkylene residue and n is 0 or an integer from 1 to 6; R10 is hydrogen, C1 -C20 alkyl or C6 -C10 aryl or C7 -C18 alkyl phenyl; and R11 is hydrogen, C1 -C20 alkyl or a residue --CH2 NR8 R9 wherein R8 and R9 have their previous significance; with (B) an organodithiophosphate having the formula: STR2 in which R13 is a C1 -C20 alkyl or C7 -C18 alkyl phenyl or C7 -C13 aralkyl group, M is a metal ion of Group IA, IB, IIA, IIB, VB, VIB, VIIB or VIII of the Periodic System of Elements, and y is the valency of M.
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