Diastereoselective addition of chlorotitanium enolate of N-acyl thiazolidinethione to O-methyl oximes: A novel, stereoselective synthesis of α,β-disubstituted β-amino carbonyl compounds via chiral auxiliary mediated azetine formation

Journal of the American Chemical Society

Volumn 125, Issue 13, 2003, Pages 3690-3691

  Ambhaikar, Narendra B ^a   Snyder, James P ^a   Liotta, Dennis C ^a  

^a EMORY UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AZETIDINE DERIVATIVE; CARBONYL DERIVATIVE; CHLOROTITANIUM ENOLATE; N ACYLTHIAZOLIDINETHIONE; O METHYL OXIME DERIVATIVE; OXIME DERIVATIVE; THIAZOLE DERIVATIVE; TITANIUM DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHEMICAL MODIFICATION; CHEMICAL REACTION; CHEMICAL STRUCTURE; CHIRALITY; DIASTEREOISOMER; ENANTIOMER; STEREOCHEMISTRY; SYNTHESIS; X RAY CRYSTALLOGRAPHY;

EID: 0037414316     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja029871u     Document Type: Article

References (46)

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40. 1H NMR was employed to determine the presence and the ratio of diastereoisomers. While none of the other diastereomer was detected in any of the reactions listed in Scheme 2, a minor byproduct, 4, was detected, which provides interesting insight into the mechanistic pathway involved. (ii) In the reactions involving oxime ethers with R = phenyl, 2-phenylethyl, and cyclohexyl, none of the minor product 4 was observed after 12 h.
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46. On the basis of preliminary analyses of crude reaction mixtures, these reactions may result in low levels (< 10%) of epimerization.