DABCO catalyzed facile synthesis of highly functionalized pyrazolines from Baylis-Hillman acetates and ethyl diazoacetate

Tetrahedron Letters

Volumn 51, Issue 50, 2010, Pages 6507-6510

  Krishna, Palakodety Radha ^a   Prapurna, Y Lakshmi ^a  

^a INDIAN INSTITUTE OF CHEMICAL TECHNOLOGY   (India)

Author keywords

Baylis Hillman acetates; DABCO; Ethyl diazoacetate (EDA); Reattack of acetate ion (acetate, rearrangement)

Indexed keywords

1,4 DIAZABICYCLO[2.2.2]OCTANE; ACETIC ACID; AROMATIC COMPOUND; DIAZOACETIC ACID ETHYL ESTER; PYRAZOLINE DERIVATIVE;

ARTICLE; BAYLIS HILLMAN REACTION; CYCLIZATION; DIASTEREOISOMER; DRUG SYNTHESIS; ISOMERIZATION; REACTION OPTIMIZATION; REACTION TIME; STEREOCHEMISTRY;

EID: 78650239518     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2010.10.006     Document Type: Article

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22. The formation of B from A is preferred due to allylic hydrogen shift which may de induced by DABCO (shown below) that further results in stereochemically favorable major products 1b-4b. Chimical equation represented
23. 4), and purified by column chromatography (silica gel, 60-120 mesh, EtOAc:n-hexane, 1:9-2:8) to afford the products.
24. 4: C, 58.19; H, 7.51; N, 10.44. Found: C, 58.16; H, 7.55; N, 10.41.