Reactivity for the Diels–Alder Reaction of Cumulenes: A Distortion-Interaction Analysis along the Reaction Pathway

2014 ◽  
Vol 118 (14) ◽  
pp. 2638-2645 ◽  
Author(s):  
Song Liu ◽  
Yu Lei ◽  
Xiaotian Qi ◽  
Yu Lan
Keyword(s):  
Interaction Analysis ◽  
Reaction Pathway ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction

ChemInform Abstract: A Novel and Efficient Tandem Aldol Condensation-Diels-Alder Reaction Pathway for the Direct Synthesis of Dehydrodecaline Derivatives.

ChemInform ◽  
2012 ◽  
Vol 43 (50) ◽  
pp. no-no
Author(s):  
M. Saeed Abaee ◽  
Mohammad M. Mojtahedi ◽  
Farveh Saberi ◽  
Ghazal Karimi ◽  
M. Taghi Rezaei ◽  
...  
Keyword(s):  
Aldol Condensation ◽  
Reaction Pathway ◽  
Direct Synthesis ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction

Diels‐Alder reaction rate in the solid state and the evidence of the location of molecular complexes between the reagents on the reaction pathway

2020 ◽  
Vol 53 (2) ◽  
pp. 207-212
Author(s):  
Vladimir D. Kiselev ◽  
Anastasia O. Kolesnikova ◽  
Ildar F. Dinikaev ◽  
Alexey A. Shulyatiev ◽  
Alexander E. Klimovitskii ◽  
...  
Keyword(s):  
Solid State ◽  
Reaction Rate ◽  
Reaction Pathway ◽  
Molecular Complexes ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction

A Novel and Efficient Tandem Aldol Condensation-Diels-Alder Reaction Pathway for the Direct Synthesis of Dehydrodecaline Derivatives

Synlett ◽  
2012 ◽  
Vol 23 (14) ◽  
pp. 2073-2076 ◽  
Author(s):  
M. Abaee ◽  
Mohammad Mojtahedi ◽  
Farveh Saberi ◽  
Ghazal Karimi ◽  
M. Rezaei ◽  
...  
Keyword(s):  
Aldol Condensation ◽  
Reaction Pathway ◽  
Direct Synthesis ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction

scholarly journals REACTION OF PYRIDO[2,1-a]ISOINDOLE WITH З (R)- AND (S)- N-α-METHILBENZYLMALEIMIDE

2020 ◽  
pp. 44-47
Author(s):  
T. Yegorova ◽  
B. Barnych ◽  
Z. Voitenko
Keyword(s):  
Double Bond ◽  
Reaction Pathway ◽  
Twist Angle ◽  
Alder Reaction ◽  
Sigmatropic Rearrangement ◽  
Diels Alder ◽  
Exocyclic Double Bond ◽  
Slow Rotation ◽  
Diels Alder Reaction ◽  
Sigmatropic Shift

Selective chemical reactions create new possibilities for controlled synthesis of compounds with pre-designed properties for further use in medical chemistry, material science and other fields. This is especially useful for such synthetic methodology as [4+2] cycloaddition. Current work is dedicated to study of reactions between N-chiral maleinimides with cyclic dienes based on the pyridoisoindol. Pyrido[2,1-a]isoindol turned out to be the most practical object to study the first example of asymmetric variant of the Diels-Alder reaction involving condensed isoindols. Previously, we established that this heterocyclic system, in contrast to other azino- and azoloisoindols, upon undergoing cycloaddition with non-chiral maleinimides gives only rearranged adducts of the first type. This type of compounds have also interesting stereochemistry: in solid state they have twisted double bond (twist angle 7-10°), while in solution they exist as a mixture of athropodiastereomeres due to the asymmetric Carbon atom and hindered rotation around С–С bond between exocyclic double bond and 2-(α-pyridil)phenyl fragment. Initial expectation was that chiral induction would influence the ratio of corresponding athropodiastereomeres. Calculations show that there are four possible athropodiastereomeres due to the chiral center and sterically hindered chiral axis. In case of non-chiral dienophiles, reaction results in two major diastereomeres (for our purposes marked as A and B) with 70:30 ration and two minor isomers (marked С and D respectively), the latter constituting less than 5% of the total amount. Major and minor isomers are in constant complex equilibrium, controlled via slow rotation of around corresponding С-С bond on one hand (which is the reason for athropodiastereomeres between major forms A and B, shown via NMR spectra at different temperatures), and on the other hand – fast equilibrium due to the 1,5-sigmatropic shift (cause for the minor forms C and D). Target reaction was studied under standard conditions for this rearrangement and under the kinetic control in the inert atmosphere at -80°С using TiCl4 as catalyzer. We therefore show that reaction pathway is similar to our previous examples and results in rearranged adducts of the first type. Ratio of athropodiastereomeres (both major and minor forms) is different from previous examples using non-chiral 2-substituted maleimides. Asymmetric induction spontaneously transfers from influencing the Diels-Alder reaction to influencing synchronic sigmatropic rearrangement, which is the final stage in the formation of the rearranged adduct of the first type in condensed isoindol systems.

scholarly journals A Diels-Alder Reaction Between A Cigarette Mainstream Smoke Component and Benzoquinone

2008 ◽  
Vol 23 (3) ◽  
pp. 121-136
Author(s):  
WM Coleman
Keyword(s):  
Gas Chromatography ◽  
Cigarette Smoke ◽  
Reaction Pathway ◽  
Atomic Emission ◽  
Alder Reaction ◽  
Diels Alder ◽  
Mainstream Smoke ◽  
Additional Information ◽  
Diels Alder Reaction ◽  
Cigarette Mainstream Smoke

AbstractA notable amount of research has been placed toward understanding the roles of benzoquinone (Q) and hydroquinone (HQ) in the chemistry and toxicity of cigarette smoke. To further understanding of the roles of these compounds in cigarette smoke, a series of reactions were performed wherein the levels and chemistries of Q and HQ were monitored after having been added to selected phases of the mainstream smoke from 2R4F cigarettes. Through the application of both fundamental organic chemistry reaction mechanistic principles and qualitative analysis of smoke chemistry, a new reaction pathway for mainstream smoke components was elucidated. During the course of these investigations, the presence of a product from a Diels-Alder reaction between a 2R4F cigarette mainstream smoke component and Q was discovered. Data from carbon-13 nuclear magnetic resonance (13C NMR), gas chromatography-atomic emission detection (GC-AED), and gas chromatography-mass selective detection (GC-MSD) revealed a Diels-Alder reaction product resulting from the reaction of benzoquinone (Q), a dienophile, and 1,3-cyclopentadiene, a diene, to yield tricyclo[6.2.1.02,7] undeca-4,9-diene-3,6-dione, more commonly referred to as cyclopentadienebenzoquinone. The reaction between Q and 1,3-cyclopentadiene was observed to have occurred when fresh mainstream vapor phase smoke (MSVP) from a 2R4F cigarette, captured in acetone, was subsequently treated with Q. Other 13C containing species were detected but inadequate signal to noise values prevented structural assignments. Accompanying the Diels-Alder reaction was an additional reaction of Q to form hydroquinone (HQ). These reactions provide additional information on the complexity of cigarette smoke, particularly as it relates to possible reactions involving Q and HQ and other cigarette smoke components.

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

Synlett ◽  
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

The intermolecular anthracene-transfer in a regiospecific antipodal C60 difunctionalization

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>

Sign in / Sign up

Export Citation Format

Share Document