Cascade cyclization of 1-(2-yl-3-phenylprop-2-enyl)-6-oxo-1,6-dihydropyridine-2-carbonitrile radical: Mechanistic insights from DFT study

Yuan, Lamei; Yu, Haitao

doi:10.1016/j.comptc.2014.06.004

Cited by 6 publications

(3 citation statements)

References 117 publications

(111 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, in the current study, the exo-adduct is kinetically and thermodynamically more favorable than endo-adduct. Similar results were found for the [4+2] cycloaddition reaction of Zn-porphyrin trimer with butadiyne, nitroalkenes with methyl vinyl ether and intermolecular cycloaddition reaction of (Z)-1-(2-iodo-3phenylprop-2-enyl)-6-oxo-1,6-dihydropyridine-2-carbonitrile (Avalos, et al, 2000;Clyde-Watson, et al, 1998;Yuan and Yu, 2014).…”

Section: Resultssupporting

confidence: 83%

Theoretical Study of the [4+2] Cycloaddition Reaction of Trifluoroethylene with Five-membered Chalcogens Heterocyclic Compounds

Mohammad‐Salim

Abdallah

2019

ARO

View full text Add to dashboard Cite

4+2] cycloaddition reaction has enormous significant in organic chemistry synthesis reactions and yet remains unexplored for the synthesis of fluorine-containing compounds. A density functional theory study of the stereo-and regioselectivity of the [4+2] cycloaddition reaction of trifluoroethylene with furan, thiophene, and selenophene was carried out in the gas phase. The B3LYP functional is used throughout in combination with 6-31G(d) basis set. The analysis of stationary points and the energetic parameters indicates that the reaction mechanism is concerted and confirms that the exo-adducts are thermodynamically and kinetically more favored than endo-adducts. The calculated branching ratio indicates that the exo-adducts have the higher percent yield than endoadducts and the yield of endo-adducts is increased only slightly on proceeding from furan, through thiophene, and onto selenophene. The analysis of the frontier molecular highest occupied molecular orbital (MO) and lowest unoccupied MO orbitals indicates that the exo-adducts are more stable due to their higher energy gab. The reaction energies were compared to the MP2/6-31G(d) and CCSD(T)/6-31G(d) calculations.Index Terms-Density functional theory, B3LYP, Regioselectivity, Stereoselectivity, [4+2] Cycloaddition.

show abstract

Section: Resultssupporting

confidence: 83%

Theoretical Study of the [4+2] Cycloaddition Reaction of Trifluoroethylene with Five-membered Chalcogens Heterocyclic Compounds

Mohammad‐Salim

Abdallah

2019

ARO

View full text Add to dashboard Cite

show abstract

“…All these possibilities were investigated and are presented in the Supporting Information (Schemes S2, S4, Table S3). [17] Starting from system A,c omprising am odel yne-ynamide and the benzothiyl radical, two pathways can provide pyrroles.T he radical can attack the internal propargyl alkyne carbon to give B, [18] which then undergoes a5 -exo-dig cyclization to yield C. [19] Thefirst step is endergonic by 9.2 kcal mol À1 ,and the second one is exergonic by 17.0 kcal mol À1 .T he corresponding transition states have free energies of 16.9 and 17.5 kcal mol À1 . TheB 3LYP functional remains widely used in the computational study of radicals.…”

mentioning

confidence: 99%

“…TheB 3LYP functional remains widely used in the computational study of radicals. [17] Starting from system A,c omprising am odel yne-ynamide and the benzothiyl radical, two pathways can provide pyrroles.T he radical can attack the internal propargyl alkyne carbon to give B, [18] which then undergoes a5 -exo-dig cyclization to yield C. [19] Thefirst step is endergonic by 9.2 kcal mol À1 ,and the second one is exergonic by 17.0 kcal mol À1 .T he corresponding transition states have free energies of 16.9 and 17.5 kcal mol À1 . [20] Radical C is then likely to abstract ahydrogen atom from thiophenol to give D.T he latter should then easily tautomerize to the aromatic 4-thioaryl-pyrrole E,w hich displays the experimentally observed regiochemistry.I ft he benzothiyl radical attacks the internal ynamide carbon, vinyl radical H would be formed.…”

mentioning

confidence: 99%

Alkyne Versus Ynamide Reactivity: Regioselective Radical Cyclization of Yne‐Ynamides

et al. 2019

View full text Add to dashboard Cite

show abstract

Alkyne Versus Ynamide Reactivity: Regioselective Radical Cyclization of Yne‐Ynamides

et al. 2019

View full text Add to dashboard Cite

Ynamides are typically more reactive than simple alkynes and olefins. However, a serendipitous observation revealed a rare case where the reactivity of simple alkynes exceeds that of ynamides. This led to the development of a unique sulfur‐radical‐triggered cyclization of yne‐tethered ynamides, which involves attack of the alkyne by a thiyl radical followed by cyclization with the ynamide. A wide range of novel 4‐thioaryl pyrroles that could tolerate common functional moieties and N‐protecting groups were expediently constructed by this strategy. The current method contrasts with the typical cyclization of yne‐ynamides, which involves the attack of the alkyne moiety by the ynamide core. Control experiments and DFT calculations supported the participation of the sulfur radical in the reaction and the regioselective cyclization. The synthetic potential of the substituted pyrroles is also discussed.

show abstract

Cascade cyclization of 1-(2-yl-3-phenylprop-2-enyl)-6-oxo-1,6-dihydropyridine-2-carbonitrile radical: Mechanistic insights from DFT study

Cited by 6 publications

References 117 publications

Theoretical Study of the [4+2] Cycloaddition Reaction of Trifluoroethylene with Five-membered Chalcogens Heterocyclic Compounds

Theoretical Study of the [4+2] Cycloaddition Reaction of Trifluoroethylene with Five-membered Chalcogens Heterocyclic Compounds

Alkyne Versus Ynamide Reactivity: Regioselective Radical Cyclization of Yne‐Ynamides

Alkyne Versus Ynamide Reactivity: Regioselective Radical Cyclization of Yne‐Ynamides

Contact Info

Product

Resources

About