Microwave Thermal Effect on Diels-Alder Reaction of Furan and Maleimide

Background: Higher temperature regions (hot spots) have been observed in organic reactions and are attributed to microwave selective heating. The accumulated heat in reaction systems accelerates certain reactions. Methods: The theoretical calculation was applied to select a suitable Diels-Alder reaction as a molecular probe to determine the microwave thermal effect on Diels-Alder reaction, one class of bimolecular reactions. The kinetic investigations were utilized to determine the reaction activation energies and further to calculate the actual reaction temperatures under different microwave conditions from the Arrhenius equation. Results: On the basis of the theoretical calculational results, Diels-Alder reaction of furan and maleimide was selected as a molecular probe to determine the microwave thermal effect in Diels- Alder reaction. Their activation energies under thermal conditions were determined from kinetic data by using the Arrhenius equation. The actual reaction temperatures under different microwave conditions were further deduced from their activation energies and the Arrhenius equation. Conclusion: Higher temperature regions (hot spots) were observed in Diels-Alder reaction, and they are more obvious in less polar solvents than those in more polar solvents in the microwave irradiated reactions.

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Kinetic Study of the Diels-Alder Reaction of Cyclopentadiene with Bis(2-Ethylhexyl) Maleate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.541 ◽

2013 ◽

Vol 634-638 ◽

pp. 541-545 ◽

Cited By ~ 3

Author(s):

Jun Seong Park ◽

Dae Hee Yun ◽

Tae Won Ko ◽

Yong Sung Park ◽

Je Wan Woo

Keyword(s):

Kinetic Study ◽

Reaction Temperature ◽

Atmospheric Pressure ◽

Arrhenius Equation ◽

Alder Reaction ◽

Diels Alder ◽

Influence Of Temperature ◽

Diels Alder Reaction ◽

Influence Of Temperature On ◽

Kinetics Of

The kinetics of the Diels-Alder reaction of cyclopentadiene with bis(2-ethylhexyl) maleate has been studied at temperatures between 25 and 100 °C and at atmospheric pressure. The influence of temperature on the kinetic constants was determined by fitting the results to the Arrhenius equation. As a result, fitting line similar with the linear curve of the Arrhenius equation at 25, 30 and 40 °C. However, the fitting curve, at 60, 80 and 100 °C, tended towards the outside of the curve in the form of Arrhenius equation. The ratio of endo/exo was a slight change from increase of the reaction temperature.

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Reactivity descriptor for the retro Diels–Alder reaction of partially saturated 2-pyrones: DFT study on substituents and solvent effects

RSC Advances ◽

10.1039/c6ra22303f ◽

2016 ◽

Vol 6 (103) ◽

pp. 101697-101706 ◽

Cited By ~ 18

Author(s):

Tuhin S. Khan ◽

Shelaka Gupta ◽

Md. Imteyaz Alam ◽

M. Ali Haider

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Density Functional ◽

Alder Reaction ◽

Diels Alder ◽

Polar Solvents ◽

Functional Theory ◽

Partially Saturated ◽

Diels Alder Reaction ◽

Reactivity Descriptor

The retro-Diels–Alder (rDA) reaction of partially saturated 2-pyrones were studied using density functional theory (DFT) calculations in polar and non-polar solvents, and fundamental descriptors were proposed to understand the electronic and solvent effect.

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Struktur und Reaktivität von isoanellierten heterocyclischen Systemen mit 4nπ- und (4n+2)π-Elektronen, XVII [1] Diels-Aider- und Michael-Additionsreaktionen von 3-Alkoxy-2,4-dihydropyrrolo[3,4-b]indolen mit Ethindicarbonsäuredialkylestern / Structure and Reactivity of Isoannelated Heterocyclic Systems with 4nπ- and (4n+2)π-Electrons, XVII [1] Diels-Alder and Michael Addition Reactions of 3-Alkoxy-2,4-dihydropyrrolo[3,4-b]indoles with Dialkyl Acetylenedicarboxylates

Zeitschrift für Naturforschung B ◽

10.1515/znb-1988-1221 ◽

1988 ◽

Vol 43 (12) ◽

pp. 1656-1661 ◽

Cited By ~ 3

Author(s):

Gerald Dyker ◽

Richard P. Kreher

Keyword(s):

Michael Addition ◽

Isotopic Labeling ◽

Alder Reaction ◽

Diels Alder ◽

Addition Reactions ◽

Current Interest ◽

Polar Solvents ◽

Dialkyl Acetylenedicarboxylates ◽

Diels Alder Reaction

Abstract The reactions of 2-rm-butyl-3-methoxy-4-methyl-2,4-dihydropyrrolo[3,4-b]indole (3) with dialkyl acetylenedicarboxylates are decisively influenced by the solvent. In the presence of alcohols as protic and polar solvents Michael addition is prefered, while in aprotic and less polar solvents like ether the Diels-Alder reaction is favoured. Based on stereospecific hydrolysis and isotopic labeling dipolar intermediates are discussed. The results are of current interest for mechanistic and theoretical reasons

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Preparation and Properties of Rubberlike High Polymers. II. Polymerization of Mixtures in Bulk

Rubber Chemistry and Technology ◽

10.5254/1.3543272 ◽

1947 ◽

Vol 20 (2) ◽

pp. 380-391

Author(s):

C. Koningsberger ◽

G. Salomon

Keyword(s):

Mechanical Properties ◽

Alder Reaction ◽

Diels Alder ◽

The Other ◽

New Class ◽

Diels Alder Reaction ◽

Vinyl Compound ◽

Other Hand ◽

Higher Temperature ◽

High Polymers

Abstract Mixtures of butadiene and dimethylbutadiene with varying quantities of styrene and acrylonitrile were copolymerized under various catalytic conditions at 100° C. The formation of cyclic dimers from dienes and vinyl compounds is, in some cases, much more pronounced than the dimerization of the dienes alone. Since the latter is also a kind of Diels-Alder reaction, a series with increasing dienophilic properties can be established from a comparison of the yields of cyclic dimers. From solubility and swelling experiments it is evident that the polymers prepared from butadiene and the vinyl compounds and those from dimethylbutadiene and acrylonitrile are true copolymers. The mechanical properties of the copolymers from butadiene and increasing amounts of a vinyl compound change gradually from those of a rubber to those of the polyvinyl compound. The copolymers from a mixture containing 30 per cent styrene or acrylonitrile are very similar to Buna-S and Perbunan, respectively. Copolymers of the same composition from dimethylbutadiene and acrylonitrile, on the other hand, form a new class of thermoplastics with a much higher temperature of elasticity.

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The Diels-Alder Reaction of 2-Ethenyl-1,4-Benzodioxin: A New and Simple Synthesis of Bisaryl Ethers

Synlett ◽

10.1055/s-1989-20343 ◽

1989 ◽

Vol 1989 (01) ◽

pp. 30-32

Author(s):

Thomas V. Lee ◽

Alistair J. Leigh ◽

Christopher B. Chapleo

Keyword(s):

Alder Reaction ◽

Diels Alder ◽

Simple Synthesis ◽

Diels Alder Reaction

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Asymmetric aza-Diels-Alder reaction of Danishefsky’s diene with imines in a chiral reaction medium

10.3390/ecsoc-10-01378 ◽

2006 ◽

Author(s):

Giang Vo-Thanh ◽

Bruce Pégot ◽

Olivier Van Buu ◽

Didier Gori

Keyword(s):

Reaction Medium ◽

Alder Reaction ◽

Diels Alder ◽

Diels Alder Reaction ◽

Danishefsky's Diene

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The intermolecular anthracene-transfer in a regiospecific antipodal C60 difunctionalization

10.26434/chemrxiv.11968743.v2 ◽

2020 ◽

Author(s):

Radu Talmazan ◽

Klaus R. Liedl ◽

Bernhard Kräutler ◽

Maren Podewitz

Keyword(s):

Noncovalent Interactions ◽

Interaction Model ◽

Alder Reaction ◽

Diels Alder ◽

Stacking Interactions ◽

Pi Stacking ◽

Diels Alder Reaction ◽

Double Decker ◽

Anthracene Molecule ◽

New Strategies

We analyze the mechanism of the topochemically controlled difunctionalization of C60 and anthracene, where an anthracene molecule is transferred from one C60 monoadduct to another one under exclusive formation of equal amounts of C60 and the difficult to make antipodal C60 bisadduct. Our herein disclosed dispersion corrected DFT studies show the anthracene transfer to take place in a synchronous retro Diels-Alder/Diels-Alder reaction: an anthracene molecule dissociates from one fullerene under formation of an intermediate, while already undergoing stabilizing interactions with both neighboring fullerenes, facilitating the reaction kinetically. In the intermediate, a planar anthracene molecule is sandwiched between two neighboring fullerenes and forms equally strong "double-decker" type pi-pi stacking interactions with both of these fullerenes. Analysis with the distorsion interaction model shows that the anthracene unit of the intermediate is almost planar with minimal distorsions. This analysis sheds light on the existence of noncovalent interactions engaging both faces of a planar polyunsaturated ring and two convex fullerene surfaces in an unprecedented 'inverted sandwich' structure. Hence, it sheds light on new strategies to design functional fullerene based materials.<br>

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