Topic
Morpholine
About: Morpholine is a research topic. Over the lifetime, 5411 publications have been published within this topic receiving 51063 citations. The topic is also known as: diethylene imidoxide & diethylene oximide.
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TL;DR: In this paper, a new 1,4 disubstituted-1,2,3-triazole product, named 4-[1-(4-methoxy-phenyl)-1H]-triazol-4-ylmethyl]-morpholine (MPTM) was successfully synthesized under click chemistry regime.
23 citations
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TL;DR: In this paper, a COF with morpholine named as KIUB-MOF-1 was successfully synthesized by using simple method in excellent yield and characterized by using FTIR, SEM, BET and XRD.
23 citations
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TL;DR: A kinetic study for reactions of 4-nitrophenyl 3,5-dinitrobenzoate with a series of cyclic secondary amines in acetonitrile is reported, and plots of the pseudo-first-order rate constant (kobsd) vs [amines] curve upward, while those of kobsd /[amine] vs [amine] exhibit excellent linear correlations with positive intercepts, indicating that the reaction proceeds through both uncatalyzed and catalyzed
Abstract: A kinetic study for reactions of 4-nitrophenyl 3,5-dinitrobenzoate (1a) with a series of cyclic secondary amines in acetonitrile is reported. Plots of the pseudo-first-order rate constant (kobsd) vs [amine] curve upward, while those of kobsd /[amine] vs [amine] exhibit excellent linear correlations with positive intercepts, indicating that the reaction proceeds through both uncatalyzed and catalyzed routes. Bronsted-type plots for uncatalyzed and catalyzed reactions are linear with βnuc = 1.03 and 0.69, respectively. The ΔH⧧ and ΔS⧧ values measured for the catalytic reaction with morpholine are −0.80 kcal/mol and −61.7 cal/(mol K), respectively. The negative ΔH⧧ with a large negative ΔS⧧ suggests that the reaction proceeds through a highly ordered transition state (i.e., a six-membered cyclic transition state, which includes a second amine molecule that accepts a proton from the aminium moiety of the zwitterionic tetrahedral intermediate and simultaneously donates a proton to the aryloxyl oxygen of the nu...
23 citations
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TL;DR: In this article, the reactions of pentafluoropyridine and 2,4,6-trifluorbyridine with a series of primary and secondary amines were studied.
Abstract: The reactions of pentafluoropyridine and 2,4,6-trifluoropyridine with a series of primary and secondary amines were studied. Whereas the nucleophilic aromatic substitution of pentafluoropyridine occurs with high regioselectivity in all cases, providing the expected 4-aminopyridine derivatives in excellent yields, the regioselectivity of 2,4,6-trifluoropyridine is dependent on the steric hindrance of the attacking nucleophile. Small nucleophiles such as morpholine attack the 4-position of the pyridine ring with high preference, but more bulky diamines attack the 2- and 4-positions leading to the formation of three regioisomeric products. (R,R)-1,2-Diaminocyclohexane as moderately bulky diamine reacted with 2,4,6-trifluoropyridine to afford the desired bis(4-aminopyridinyl)cyclohexane derivative in 30% yield. For hydrodefluorination two methods were examined. A two-step procedure employing hydrazine and subsequently copper(II) sulfate removed just one fluorine substituent, but is not sufficiently high yielding for the reduction of more complex substrates. With the system titanocene difluoride as pre-catalyst and diphenylsilane as reducing agent we were able to selectively remove fluorine substituents at positions C-2 and C-4 of a variety of 4-aminopyridine derivatives. This protocol allows the synthesis of compounds such as the divalent chiral 4-(dimethylamino)pyridine (DMAP) analogue (R,R)-trans-N,N′-dimethyl-N,N′-bis(pyridin-4-yl)cyclohexane-1,2-diamine with fair overall yield.
23 citations
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TL;DR: Optically pure (R)-(1-naphthylmethyl)succinic acid could be efficiently prepared by a combination of optical resolution and racemization of the undesired enantiomer as discussed by the authors.
23 citations