Showing papers on "Morpholine published in 1991"
TL;DR: In this article, methyl sulfenylation of 1-substituted pyrroles and indoles was observed using 1-(methylthio)morpholine and an acid catalyst or with methylsulfenyl chloride and excess pyridine.
52 citations
TL;DR: In this paper, the use of two different allylic handles has been investigated in the solid-phase synthesis of protected peptides, under mild conditions which preserve side-chain protecting groups can be achieved by carrying out the cleavage reaction in 2:2:1 THF/DMSO/0.5 M HCl, using morpholine as nucleophile and Pd(Ph 3 P) 4 as catalyst.
49 citations
TL;DR: In this article, the nucleophilic substitution reactions of aromatic halides having electron-attracting groups on ortho or para position with various primary and secondary amines were accelerated by high pressure to give the corresponding N-substituted anilines in high yields.
Abstract: The nucleophilic substitution reactions of aromatic halides having electron-attracting groups on ortho or para position with various primary and secondary amines were accelerated by high pressure to give the corresponding N-substituted anilines in high yields. The bulkiness of amines affects its reactivity to lower the yields of the products. Although the secondary amines are usually less reactive than primary amines, cyclic secondary amines such as morpholine, piperidine, and pyrrolidine were found very reactive. 1,4-Diazabicyclo[2.2.2]octane and quinuclidine gave N-quaternary ammonium halides in high yields in contrast to the low reactivity of acyclic tertiary amines. Dichloro- and trichloro-nitrobenzenes also react with diethylamine, pyrrolidine, and morpholine to give mono-, di-, and trisubstitution products depending upon the amount of amine and the position of nitro group in these chlorides.
40 citations
34 citations
TL;DR: It is shown that morpholine is initially catabolised by an analogous route to pyrrolidine, producing 2(2-aminoethoxy)acetate which can be oxidatively cleaved to give rise directly to glycollate and indirectly to ethanolamine.
Abstract: When Mycobacterium strain MorG was grown with morpholine as sole source of carbon and nitrogen, enzymes for ethanolamine catabolism (via the ethanolamine-O-phosphate pathway) and glycollate catabolism (via the glycerate pathway) were strongly induced. Almost all morpholine-negative (Mor−) mutants of MorG failed to utilize glycollate as a carbon source and were shown to be effective in one or more enzymes for its metabolism via the glycerate pathway. Growth of MorG with morpholine also induced the jacoby and Fredericks pathway for pyrrolidine catabolism, Mor− mutants had invariably lost the ability to grow on pyrrolidine and 2(2-aminoethoxy)acetate was shown to be an intermediate in morpholine catabolism. This indicates that morpholine is initially catabolised by an analogous route to pyrrolidine, producing 2(2-aminoethoxy)acetate which can be oxidatively cleaved to give rise directly to glycollate and indirectly to ethanolamine.
32 citations
TL;DR: In the same solvent, the reaction of the hydroxo-nickel complex with carbon disulphide and [NBu4]OH leads to the formation of the dithiocarbonate complex.
30 citations
TL;DR: The combination of an anchor for solid phase synthesis which allows release of fully protected oligonucleotide analogues from the solid support and base protective groups which provide water solubility has been shown to facilitate isolation, purification, and characterization of neutral oligon DNA analogues derived from morpholine nucleosides.
29 citations
TL;DR: In this paper, a reductive cyclization procedure preserving the configuration of the preexistant asymetric centers and proceedings stereoselectively (in more favorable cases stereospecifically) when creating a new asymmetric center was proposed.
26 citations
TL;DR: In this article, the kinetics of the reaction of benzylidenemalonodialdehyde with piperidine, morpholine, n-butylamine, 2-methoxyethylamine and semicarbazide have been determined in 50% aqueous Me 2 SO at 20 o C. Intrinsic rate constants (κ 0 =κ 1 =κ −1 ) and the pK a of T A ±, were determined for all the amines.
Abstract: The kinetics of the reaction of benzylidenemalonodialdehyde with piperidine, morpholine, n-butylamine, 2-methoxyethylamine, glycinamide, glycine ethyl ester, cyanomethylamine, and semicarbazide have been determined in 50% aqueous Me 2 SO at 20 o C. The reaction leads to a zwitterionic adduct, PhCH(RR'NH + )C(CHO) 2 − (T A ± ), that is in fast acid-base equilibrium with the anionic adduct, PhCH(RR'N)C(CHO) 2 − (T A − ). With strongly basic amines at high pH there is also attack of the amine on one of the carbonyl groups, which acts as a rapid preequilibrium. Rate constants for the formation of T A ± (κ 1 ) and its reverse (κ −1 ), as well as equilibrium constants (K 1 =κ 1 /κ −1 ) and the pK a of T A ± , were determined for all the amines. Intrinsic rate constants (κ 0 =κ 1 =κ −1 ) and the pK a of T A ± , were determined for all the amines. Intrinsic rate constants (κ 0 =κ 1 =κ −1 when K 1 =1) were calculated
25 citations
24 citations
TL;DR: In this paper, the reaction rates of the cleavage of phthalimide (PTH) were studied at 30°C in buffer solutions of trimethylamine, triethylamines, triethanolamine and carbonate.
TL;DR: In this article, the NC-coupling of the two neighbouring isocyano functions was proposed to give a benzimidazole ring system, and the transfer of the exocyclic Au(CI)C fragment onto the incoming amine.
TL;DR: In this article, the rates of reversible deprotonation of 3,5-heptanedione (6b), 2,6-dimethyl-3,5heptane (6c), and dibenzoylmethane(6d) were measured in 50% Me 2 SO-50% water (v/v) at 20 o C. The pK a and K T values show the same trends observed previously in water.
Abstract: Rates of reversible deprotonation of 3,5-heptanedione (6b), 2,6-dimethyl-3,5-heptanedione (6c), and dibenzoylmethane (6d) by several primary aliphatic amines, by piperidine and morpholine, and by hydroxide ion (6b and 6d only) have been measured in 50% Me 2 SO-50% water (v/v) at 20 o C. Apparent pK a 's as well as the pK a values of the keto and the enol forms, and the enolization equilibrium constantes (K T ) were also determined. The pK a and K T values show the same trends observed previously in water. The intrinsic rate constants for the reactions of 6b and 6c with a given family of amines (primary aliphatic or secondary alicyclic) and the same and also equal to those for the reaction of acetylacetone (6a) with the same amines determined previously. These results indicate that steric effects play an insignificant role in the reactions of 6a, 6b, and 6c
TL;DR: Aminoethers were electrofluorinated in anhydrous hydrogen fluoride, the corresponding saturated perfluoroaminoethers being the largest individual substances in each case as discussed by the authors.
TL;DR: In this article, a sterical model of the mechanism of electrochemical fluorination of α, ω-dimorpholino- and dipiperidino-alkanes of different chain length (n = 1-6) and morpholinocyclohexene gave the perfluoro derivatives.
TL;DR: The photochemical synthesis of the 18-membered lichen macrolide (+)-aspicilin (1a) is characterized by the successful use of photolactonization as a key reaction and by diastereoselective generation of stereogenic centers C(4), C(5), and (C(6) as mentioned in this paper.
TL;DR: In this paper, the kinetics of the reactions of benzylidene-1,3-indandione with piperidine, morpholine, n-butylamine, 2-methoxyethylamine and glycinamide, and cyanomethylamine were measured in 50% Me 2 SO-50% water (v/v) at 20°C and 0.5 M ionic strength.
Abstract: The kinetics of the reactions of benzylidene-1,3-indandione with piperidine, morpholine, n-butylamine, 2-methoxyethylamine, glycinamide, and cyanomethylamine and the reactions of benzylidene-3,5-heptanedione, benzylidene-2,6-dimethyl-3,5-heptanedione, and benzylidenedibenzoylmethane with piperidine and morpholine have been measured in 50% Me 2 SO-50% water (v/v) at 20°C and 0.5 M ionic strength. The reactions lead, in all cases, to the reversible formation of the zwitterionic adduct PhCH(RR'NH + )C(COX) 2 − (T A ± ) that is in fast equilibrium with its anion PhCH(RR'N)C-(COX) 2 − (T A − )
TL;DR: In this article, two synthesized 2-morpholine carboxylic acid derivatives are described, and the esters were converted into 1-aza-4-oxabicyclo[3.3.1]non-6-one, the first example of this ring system, which was further elaborated to the ortho-methoxy benzamide derivative.
TL;DR: In this paper, a sterical model of the mechanism of electrochemical fluorination based on a linear model is presented. And the crystal structure for F-dimorpholinobutane is provided.
TL;DR: In this article, the Ga 2 I 4 ·2L (L = pyridine, 2-methylpyridine and 3-methyl pyridine) and 4-mixture of morpholine, N-methylmorpholine, 1,4-dioxan, tetrahydropyran, dimethyl sulfoxide, diethylsulphide, tetrahedron, tetramerethylbiphosphine and tetramethylbipyran have been obtained.
Journal Article•
TL;DR: Some of these amides showed platelet antiaggregating activity in vitro slightly inferior to that of acetylsalicylic acid, as well weak antiinflammatory, analgesic and antipyretic activities in rats and mice.
Abstract: The synthesis of a series of 5-substituted 4-isoxazolecarboxamides by reaction of eight 5-substituted 4-isoxazolecarbonyl chlorides with pyrrolidine, piperidine, morpholine and 4-trifluoromethylaniline is described. Some of these amides showed platelet antiaggregating activity in vitro slightly inferior to that of acetylsalicylic acid, as well weak antiinflammatory, analgesic and antipyretic activities in rats and mice.
TL;DR: In this article, NiCl2(dbmthiohydrazide) and NiCl(6H2O, NiCl 2·4H 2O, CoCl2· 6H 2 O, CoCo2· 4H 2 2 O and CoCoCl 2 · 2H 2 OD have been shown to yield complexes of the type [M(gbmth), [M=NiII, CuII or CoII], [M = NiII, CoII, etc.
Abstract: Reactions of glyoxal bis(morpholineN-thiohydrazone), H2gbmth, with NiCl2·6H2O, Ni(OAc)2·4H2O, Ni(acac)2· H2O, CuCl2·2H2O, Cu(OAc)2·H2O, Cu(acac)2, CoCl2· 6H2O, Co(OAc)2·4H2O and Co(acac)2·2H2O yield complexes of the type [M(gbmth)], [M=NiII, CuII or CoII] Diacetyl reacts with morpholineN-thiohydrazide in the presence of nickel salts to yield [NiII(dbmth)], [NiII(dmth)(OAc)]H2O and [NiII(Hdmth)(NH3)Cl2] involving N2S2 and NSO donor ligands Copper and cobalt complexes of N2S2 and NSO donor ligands with compositions [CuII(dbmth)], [CoII(dbmth)]·4H2O and [CoII(H2dbmth)]Cl2, have been isolated The compounds have been characterised by elemental analyses, magnetic moments, molar conductance values and spectroscopic (electronic and infrared) data
TL;DR: The adsorption of heterocyclic amines, such as morpholine, pyridine, picolines, quinoline, and isoquinoline from dilute aqueous streams, with or without electrolytes and at different pH, on activated carbons and polymeric adsorbent (XAD-4, Rohm and Haas), was successfully accomplished using fixed bed systems as discussed by the authors.
Abstract: The adsorption of heterocyclic amines, such as morpholine, pyridine, picolines, quinoline, and isoquinoline from dilute aqueous streams, with or without electrolytes and at different pH, on activated carbons and polymeric adsorbent (XAD-4, Rohm and Haas), was successfully accomplished using fixed bed systems A mathematical model, based on external mass transfer and pore diffusion, is used for forecasting theoretical breakthrough profiles, which have been compared with experimental results and 'by-best fit' comparison effective pore diffusion coefficient, has been found out for each adsorbate-adsorbent system The loaded adsorbents were regenerated with an organic solvent (eg, methanol) efficiently The amines can be recovered by distillation from the eluted solution
TL;DR: The ability of 10 pyrroles to block the acidic nitrosation of morpholine has been determined by using an assay that measures their effectiveness in the presence of a 10-fold excess of amine.
Abstract: The ability of 10 pyrroles to block the acidic nitrosation of morpholine has been determined by using an assay that measures their effectiveness in the presence of a 10-fold excess of amine. The log (% N-nitrosomorpholine) formed is a linear function of blocking agent concentrations ranging from 0.0 to 1.5 times the equivalents of initial nitrite. The negative slopes of these plots allow a ranking of the effectiveness of the blocking agent. Several of the pyrroles have been found to be much more effective than established blocking agents such as ascorbic acid. The following order of blocking ability has been determined: 2,5-dimethylpyrrole = 1-benzyl-2,5-dimethylpyrrole much greater than 4-methylcatechol greater than ascorbic acid = 1,2-phenylenediamine = pyrrole greater than 1,2,5-tribenzylpyrrole = 1-benzylpyrrole = octamethylporphine much greater than ammonium sulfamate = hydrazine = 2,5-diphenylpyrrole much much greater than beta-nicotyrine greater than 2-pyrrolecarboxylic acid. Pyrroles give complex mixtures devoid of N-nitroso compounds upon nitrosation.
TL;DR: In this paper, the reaction with three N,N-dialkylanidosulfenyl chlorides bearing representative sizes for the R group on the nitrogen atom has been shown to yield diastereoisomeric allenic sulfinamides.
TL;DR: In this article, the reactions of a series of methyl para-substituted phenylpropiolates with piperidine, morpholine, and diethylamine in methanol and dimethylformamide (DMF) have been studied and their rates measured.
Abstract: The reactions of a series of methyl para-substituted phenylpropiolates 1a–e with piperidine, morpholine, and diethylamine in methanol and dimethylformamide (DMF) have been studied and their rates measured. The products were methyl β-(N,N-dialkylamino)-p-substituted cinnamates 2–4a–e. 1H NMR spectra were used to determine the configuration of the products. The ρ values in methanol ranged between 0.34 and 1.24 whereas in DMF they were between 0.85 and 1.88. The values of ΔS≠ favor a bimolecular rate-limiting step mechanism. Key words: nucleophilic addition to acetylenic esters.
TL;DR: Cleavage of 3'-end-labeled DNA in hot aqueous solutions of different amines is comparatively examined for overall rate of DNA scission as well as for potential differences in the preference of the various amines for cleavage at the different bases.
TL;DR: In this paper, the activation energies and other kinetic parameters were calculated from the Coats-Redfern and Horowitz-Metzger equations, and the formation of new compounds was confirmed from the spectral data.
Abstract: The reactions of bis(2-mercaptobenzothiazolato)nickel(H) with some azoles and morpholine afforded the corresponding mixed ligand complexes. The studied azoles were 2-aminothiazole, benzothiazole, benzoxazole, 2-methylbenzoxazole and 2-mercapto-benzoxazole. The formation of new compounds was confirmed from the spectral data. The thermal decompositions of the compounds together with some related compounds reported in the literature, for comparison, were studied. The activation energies and other kinetic parameters were calculated from the Coats-Redfern and Horowitz-Metzger equations.
TL;DR: In this paper, a study was made of the influence of the composition of the Cu(II) coordination sphere on the course of the thermal decomposition of the complexes Cu4O(X+Y)6L4, whereX andY were Cl and Br, andL was piperidine or morpholine.
Abstract: A study was made of the influence of the composition of the Cu(II) coordination sphere on the course of the thermal decomposition of the complexes Cu4O(X+Y)6L4, whereX andY were Cl and Br, andL was piperidine or morpholine. The tetrahedral unit Cu4O with the oxygen atom in its centre was found to be the thermally weakest part of the complex. The decomposition temperatures of the complexes were strongly influenced by the anionsX andY and by the ligandL. The temperature at which decomposition started was found to be the lower, the more chloride anions were substituted by bromide anions. The complexes containing piperidine as ligandL exhibited higher decomposition temperatures than those with morpholine as ligand. The decompositions of all the studied complexes were accompanied by redox reactions. The only compounds identified among the decomposition intermediates by X-ray diffraction were copper(I) halides. Copper(I) bromide underwent oxidation on further heating and a mixture of CuO and CuBr was obtained as the final decomposition product.