Interferences in photodissociation in the classical limit

Lee, Chun‐Woo

doi:10.1103/physreva.37.2467

Cited by 78 publications

(28 citation statements)

References 11 publications

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“…Computational Details. Theoretical calculations have been done at the density functional level using the gradient corrected functionals of Becke and Lee, Yang, and Parr (BLYP) for exchange and correlation, respectively, and the 6-31G* basis set . All calculations have been done using the Gaussian-94 program…”

Section: Methodsmentioning

confidence: 99%

Controlling π-Facial Diastereoselectivity in the 1,3-Dipolar Cycloadditions of Diazomethane to Chiral Pentenoates and Furanones: Enantioselective Stereodivergent Syntheses of Cyclopropane Hydroxy Acids and Didehydro Amino Acids

et al. 1998

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The title compounds have been synthesized in both enantiomeric forms and in good overall yields by using d-glyceraldehyde as the single chiral precursor. The efficiency and usefulness of the synthetic routes have been secured by performing controlled manipulations of the functional groups and by highly stereoselective transformations, namely Wittig−Horner condensations and cyclopropanations. Cyclopropane derivatives have been synthesized through 1,3-dipolar cycloaddition of diazomethane to chiral pentenoates or furanones obtained, in turn, from d-glyceraldehyde. Syn/anti stereochemistry of the cycloadducts has been unequivocally assigned and rationalized. Since π-facial diastereoselectivity involved in these cycloadditions is the opposite for cyclic and open-chain structures, enantiomeric series of products can be derived.

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Section: Methodsmentioning

confidence: 99%

Controlling π-Facial Diastereoselectivity in the 1,3-Dipolar Cycloadditions of Diazomethane to Chiral Pentenoates and Furanones: Enantioselective Stereodivergent Syntheses of Cyclopropane Hydroxy Acids and Didehydro Amino Acids

et al. 1998

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“…In the DFT calculations several gradient-corrected functionals have been used. The first one, denoted BLYP, consists of the Becke exchange functional with the correlation functional of Lee, Yang, and Parr . In the second one, the hybrid Becke exchange functional has been used with the LYP correlation functional (B3LYP).…”

Section: Computational Detailsmentioning

confidence: 99%

Theoretical Study of the Mechanism of the Addition of Diazomethane to Ethylene and Formaldehyde. Comparison of Conventional ab Initio and Density Functional Methods

et al. 1998

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The 1,3-dipolar cycloaddition reactions of diazomethane with ethylene and formaldehyde as well as the nitrogen elimination reactions from the cycloadducts have been studied using density functional and conventional ab initio methods. The exothermicity of the reactions is underestimated by DFT methods with respect to CCSD(T) due to an overestimation of the C−N dissociation energy of diazomethane. For the cycloaddition reactions all methods lead to similar transition state geometries, and the potential energy barriers computed using DFT methods are similar to the CCSD(T) ones. On the other hand, for the nitrogen elimination reactions transition state geometries and energy barriers are more dependent on the level of calculation. The results obtained show that for the reaction between diazomethane and ethylene the pyrazoline intermediate is more stable than the reactants and that the Gibbs energy barrier for nitrogen elimination is larger than the barrier corresponding to its formation. On the contrary, for formaldehyde the kinetically most favorable cycloadduct, 1,2,3-oxadiazoline, is less stable than the reactants and has a lower barrier for nitrogen elimination.

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“…Transition states have been located without any geometry restriction and have been characterized through the calculation of the force constants matrix by ensuring that they correspond to saddle points of the potential energy hypersurface; i.e., they have one and only one imaginary frequency. , For the reaction between 2 an cyclopentadiene, these structures have been taken as starting points for the location of the stationary points using density functional (DF) calculations. We have used the gradient corrected functionals of Becke and Lee and Yang and Parr (B-LYP) for exchange and correlation, respectively, and the 3-21G basis set…”

Section: Computational Detailsmentioning

confidence: 99%

Effect of Lewis Acid Catalysis on the Diels−Alder Reaction between Methyl (Z)-(S)-4,5-(2,2-Propylidenedioxy)pent-2-enoate and Cyclopentadiene. A Theoretical Study

et al. 1997

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The Diels-Alder reactions of methyl (Z)-(S)-4,5-(2,2-propylidenedioxy)pent-2-enoate and (Z)-(S)-4,5-(2,2-propylidenedioxy)pent-2-enoic acid with cyclopentadiene catalyzed by AlCl(3) have been theoretically studied at the B-LYP/6-31G level. The results obtained show that the catalyst increases both the endo/exo and syn/anti selectivity, in good qualitative agreement with the experimental observations. The origin of the selectivity and the role of the catalyst are discussed.

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Interferences in photodissociation in the classical limit

Cited by 78 publications

References 11 publications

Controlling π-Facial Diastereoselectivity in the 1,3-Dipolar Cycloadditions of Diazomethane to Chiral Pentenoates and Furanones: Enantioselective Stereodivergent Syntheses of Cyclopropane Hydroxy Acids and Didehydro Amino Acids

Controlling π-Facial Diastereoselectivity in the 1,3-Dipolar Cycloadditions of Diazomethane to Chiral Pentenoates and Furanones: Enantioselective Stereodivergent Syntheses of Cyclopropane Hydroxy Acids and Didehydro Amino Acids

Theoretical Study of the Mechanism of the Addition of Diazomethane to Ethylene and Formaldehyde. Comparison of Conventional ab Initio and Density Functional Methods

Effect of Lewis Acid Catalysis on the Diels−Alder Reaction between Methyl (Z)-(S)-4,5-(2,2-Propylidenedioxy)pent-2-enoate and Cyclopentadiene. A Theoretical Study

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