A new protocol for the in situ generation of aromatic, heteroaromatic, and unsaturated diazo compounds and its application in catalytic and asymmetric epoxidation of carbonyl compounds. Extensive studies to map out scope and limitations, and rationalization of diastereo- and enantioselectivities

Journal of the American Chemical Society

Volumn 125, Issue 36, 2003, Pages 10926-10940

  Aggarwal, Varinder K ^a   Alonso, Emma ^a   Bae, Imhyuck ^a   Hynd, George ^a   Lydon, Kevin M ^a   Palmer, Matthew J ^a   Patel, Mamta ^a   Porcelloni, Marina ^a   Richardson, Jeffery ^a   Stenson, Rachel A ^a   Studley, John R ^a   Vasse, Jean Luc ^a   Winn, Caroline L ^a  

^a UNIVERSITY OF BRISTOL   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EPOXIDATION REACTIONS;

CONFORMATIONS; OXIDATION; SALTS; STEREOCHEMISTRY;

AROMATIC HYDROCARBONS;

AROMATIC COMPOUND; BENZALDEHYDE; CARBONYL DERIVATIVE; DIOXANE; ETANERCEPT; HYDRAZONE DERIVATIVE; LITHIUM; POTASSIUM SALT; SODIUM; STILBENE OXIDE; SULFIDE; TETRAHYDROTHIOPHENE DERIVATIVE;

ARTICLE; CALCULATION; CATALYSIS; CATALYST; CHEMICAL REACTION; CHEMICAL STRUCTURE; CHIRALITY; DIASTEREOISOMER; ENANTIOSELECTIVITY; EPOXIDATION; STEREOCHEMISTRY; STRUCTURE ANALYSIS; SYNTHESIS;

EID: 0041733341     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja034606+     Document Type: Article

References (74)

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69. -1, which, according to the Boltzmann equation, correlates to a ratio of 1129:1 at 40 °C. If these were both equally reactive, this would correspond to 99.8% ee.
70. For a full discussion, see: Aggarwal, V. K.; Richardson, J. Chem. Commun. 2003, in press.
71. Yields are < 10% for each of these substrates. Preliminary results suggest that using LiBr as an additive also results in higher enantioselectivity (reduced reversibility in betaine formation) without reducing yields. Full details will be published in due course.
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