Studies of mild dehydrogenations in heterocyclic systems

Tetrahedron Letters

Volumn 38, Issue 3, 1997, Pages 331-334

  Williams, David R ^a   Lowder, Patrick D ^a   Gu, Yu Gui ^a   Brooks, Dawn A ^a  

^a INDIANA UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

FUNICULOSIN; OXAZOLE DERIVATIVE; PYRIDONE DERIVATIVE; THIAZOLE DERIVATIVE;

ARTICLE; DRUG OXIDATION; DRUG SYNTHESIS; METHODOLOGY; REACTION ANALYSIS;

EID: 0031022867     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(96)02344-1     Document Type: Article

References (21)

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12. b) The 4-hydroxy-2-pyridinones, such as i, also react with trifluoromethanesulfonyl chloride to quantitatively yield ii. However, these chlorides did not eliminate to provide access to the intermediate quinone methides 11. Equation represented.
13. c) Treatment of ester enolates of oxazolines (entries 1 and 2; generated with LiHMDS; THF; -78 °C) with trifluoromethanesulfonyl chloride (3 equivs at -78 °C → 0 °C; 1 hr) directly produces the corresponding oxazoles (52%) in comparable yields to phenylselenenylation/elimination.
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15. See also: Chem. Abstr. 1986, 105, 23787n.
16. 4), filtered, and concentrated in vacuo. The residue was purified by flash chromatography (silica gel; EtOAc) providing the bis-oxazole (3.8 g, 87%) as a white solid (m.p. 154-155 °C).
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