Adducts of copper(II) acetate with amines in ethanolic solution

Copper(II) acetate was calorimetrically titrated with pyridine, 2-, 3- and 4-methylpyridine in absolute ethanol. The enthalpy of reaction and the equilibrium constant were determined for the adduct formation in solution for each ligand. The amines react with copper(II) acetate without breaking the dimeric structure at least in the limit of the concentration ratio|ligand|/|(CH₃CO₂)₄Cu₂|<2.     

Reactions of sulfites with secondary amines

The interaction of diethylamine and morpholine with diphenyl, methyl phenyl, ethyl phenyl, and isopropyl phenyl sulfites was studied. It was established that two reactions, substitution and alkylation, can occur in parallel. Diphenyl sulfites react with amines to give only substitution products, while other sulfites react with substitution at the sulfur atom and with alkylation of the amines. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1395–1397, July, 1998.     

Reactions of salicylaldehyde with tris(pentaf luorophenyl)silanes and secondary amines

Reactions of tris(pentafluorophenyl)silanes RSi(C₆F₅)₃ with salicylaldehyde and secondary amines were studied. The reactions afforded α-pentafluorophenyl-substituted amines. Silanes RSi(C₆F₅)₃ (R = Me, Ph, C₆F₅, CH₂CH=CH₂, and CH=CH₂) were found to be efficient reagents for transfer of the C₆F₅ group to the iminium cation generated from salicylaldehyde and amine. However, tris(pentafluorophenyl)phenylethynyl-and tris(pentafluorophenyl)silanes were not able to serve as a source of a fluorinated substituent because of competitive transfer of acetylenide fragment or hydride. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 498–503, March, 2006.     

Reactions of 1,3-alkadiynes (n > 4) with secondary amines

Conclusions A study was made of some regular features of the addition of secondary amines to 1,3-alkadiynes with more than four carbons in the chain.This article is published in accordance with a resolution of the Conference of Editors-in-Chief of Journals of the USSR Academy of Sciences of July 12, 1962, as a dissertation paper by E. A. Él'perina.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 1803–1806, October, 1966.     

Reactions of acyl nitroso compounds with amines: Production of nitroxyl (HNO) with the preparation of amides

Oxidation of hydroxamic acids in the presence of amines generates nitrous oxide (N₂O) and the corresponding amide. The identification of N₂O suggests the intermediacy of nitroxyl (HNO). Retro-Diels Alder dissociation of cyclopentadiene-acyl nitroso compound cycloadducts releases N₂O with amide formation.     

Reactions of (E)- and (Z)-1,3-dichloropropenes with secondary amines

An efficient procedure was developed for preparation of (E)- and (Z)-3-chloroprop-2-ne-1-ylamines from commercially available 1,3-dichloropropene.     

Reactions of imides with samarium(ii) iodide

The tendency of a series of imides and lactams to react with samarium(II) iodide was investigated. Under the action of Sml₂ at 20 °C, one of the carbonyl groups ofN-phenylphthalimide was reduced to a CHOH or CH₂ group depending on the molar ratio of the reagents and the order of their introduction into the reaction mixture. Both CO groups ofN-acetylcaprolactam are reduced with SmI₂ under similar conditions, whereas the CO group of -caprolactam is not reduced by SmI₂.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1236–1238, May, 1996.     

Reactions of 4-methoxypyrylium salts with secondary amines

4-Aminopyrylium derivatives were prepared from secondary amines and 4-methoxy-2,6-dimethylpyrylium perchlorate ( 1a ) and the corresponding 2,6-diphenyl derivative. Excess amine or elevated temperature resulted in the addition of two equivalents of amine to 1a . The reactions of the aminopyrylium salts with hydroxide, ammonia, primary amines, hydrazines, cyanoacetamides, ethyl cyanoacetate, malononitrile, nitromethane, sodium sulfide, and a Grignard reagent are described.     

Reactions of 3-iodo-7-dialkylaminocoumarins with secondary amines

The reaction of 3-iodo-7-diethylaminocoumarin and 2,3,6,7-tetrahydro-10-iodo-1H,5H-quinolizino[9,9a,1-gh]coumarin with secondary amines (diethylamine, piperidine, morpholine, imidazole, and benzimidazole) leads to 4,7-diaminocoumarins. The corresponding 3-iodo-4-chloro-7-dialkylaminocoumarins under similar conditions give 3-iodo-4,7-diaminocoumarins. 4-Aminomethyl derivatives of coumarins are formed in the reactions of 3-iodo-4-methyl-7-diethylaminocoumarin and 2,3,6,7-tetrahydro-9-methyl-10-iodo-1H,5H-quinolizino[9,9a,1-gh]coumarin with these secondary amines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 609–618, May, 1991.     

Regioselective formation of 2,5-disubstituted oxazoles via copper(i)-catalyzed cycloaddition of acyl azides and 1-alkynes

The reaction of 1-alkynes with acyl azides in the presence of [Tpm(*,Br)Cu(NCMe)]BF(4) [Tpm(*,Br) = tris(3,5-dimethyl-4-bromopyrazolyl)methane] as the catalyst provides 2,5-oxazoles in moderate to high yields. This is a novel transformation of the CuAAC type that constitutes a significant variation of the commonly observed [3 + 2] cycloaddition reaction to yield 1,2,3-triazoles.     

Reactions of (cyclopentadienyl)nitrosyldicarbonylmanganese cation with amines

The [(XC₅H₄)Mn(CO)(NO)L]⁺ complexes react with primary alkylamines to give carboxamido complexes, where X = H, CH₃; L = CO, P(C₆H₅)₃. In the case of L = CO, the carboxamido complexes may be isolated, whereas with L = P(C₆H₅)₃ the reversibility of the reactions permits the isolation only of the starting materials when the solutions are evaporated to dryness. This diminished tendency to form carboxamido complexes is related to the decreased electron density on the carbonyl carbon going from L = CO to L = P(C₆H₅)₃. The presence of the coordinated NO group does not change the reactivity of the cationic complexes towards amines.     

Reactions of lithium tributyl heteroaryl borates with allylic bromides in the presence of copper(I) cyanide

The reaction of various lithium tributylheteroarylborates with allylic bromides in the presence of copper(I) cyanide furnished the regioselective allylation at the heteroaryl ring.     

Reactions of carbethoxyalkylidenetriphenylphosphoranes with aryl azides

The title reaction has been shown to give a complex mixture of products from which triazoles (12 and 17), maleates (13), fumarates (14), triphenylphosphine oxide (15), iminophosphoranes (16) and triazenes (18) have been isolated. Their formation is rationalized by two reaction paths, involving addition of the azide onto the CC and CP bonds of the ylide. Diazoesters 5 and 19, which should result from CP addition, were not isolated, but are believed to give rise to compounds 13,14 and 18.     

A spectrometric,separation and voltammetric study of the complexation reactions of bromazepam with iron(ii),copper(ii) and cobalt(ii)

Bromazepam, in the form of a cationic iron(II) chelate, can be determined spectrophotometrically at 588 nm with a limit of detection of ca. 10^-6 M. When this chelate is ion-paired with perchlorate, it can be extracted into organic solvents such as 1,2-dichloroethane and 4-methyl-2-pentanone, and determined by atomic absorption spectrometry with a limit of detection of 1.5 × 10^-5 M bromazepam at the iron resonance 248.3-nm line. Ion-pairs involving the Fe(II), Cu(II) and Co(II) chelates and perchlorate can be separated by h.p.l.c. using a C₁₈ reverse-phase column and a mobile phase of 4:1 water—methanol, with a u.v. detector at 242 nm. This approach allowed for the determination of iron(II) ions in aqueous solution with a limit of detection of 10^-8 M. The h.p.l.c. method could also be used to quantify bromazepam spiked in plasma in the concentration range 1–10 μg ml^-1, following extraction of bromazepam from plasma and subsequent formation of the iron(II) ion-pair. Copper(II) forms a labile chelate with bromazepam in pH 4.8 acetate buffer which, when subjected to differential pulse voltammetry at the hanging mercury drop electrode, gives rise to a catalytic phenomenon which can be utilised for the determination of bromazepam in the concentration range 10^-5–10^-9 M.