Metalation of oxazole-borane complexes: A practical solution to the problem of electrocyclic ring opening of 2-lithiooxazoles

Journal of Organic Chemistry

Volumn 61, Issue 16, 1996, Pages 5192-5193

  Vedejs, Edwin ^a   Monahan, Sean D ^a  

^a UNIVERSITY OF WISCONSIN MADISON   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0000858597     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo960813z     Document Type: Article

References (32)

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21. 3-THF (6.9 mL, 1 M in THF, Aldrich). After 30 min, the solution was cooled to -78 °C, and n-BuLi (4.44 mL, 1.63 M in hexane, Aldrich) was added dropwise. After 30 min, benzaldehyde (0.77 mL, 7.58 mmol) was added. The mixture was stirred for 30 min, and 34 mL of 5% HOAc in ethanol was added. The cooling bath was removed, and the mixture was stirred for 18 h at rt to cleave the borane complex. Conventional workup (supporting information) gave 10, isolated by crystallization from ether, two crops (1.4 g, 81%).
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