a-Metalated Tertiary Enol Carbamates. New Acyl Anion Equivalents

Journal of Organic Chemistry

Volumn 55, Issue 22, 1990, Pages 5680-5683

  Sengupta, Saumitra ^a   Snieckus, Victor ^a  

^a UNIVERSITY OF WATERLOO   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0000832426     PISSN: 00223263     EISSN: 15206904     Source Type: Journal    
DOI: 10.1021/jo00309a008     Document Type: Article

References (69)

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50. All new compounds show analytical and spectral (IR, NMR, MS) data in accord with the assigned structures. Typical procedur:e A THF solution (3 mL) of 3a (179 mg, 1.25 mmol) was added via cannula to a solution of s-BuLi (1.40 mL, 0.94 M, 1.31 mmol) and TMEDA (0.20 mL, 1.32 mmol) in THF (8 mL) at -78 C. After 1 h at -78 C, TMSC1 (0.19 mL, 1.40 mmol) was added. It was quenched after 15 min with saturated NH4Cl solution. Standard workup with ether followed by flash chromatography (20 ether in hexane) gave a clear liquid: 228 mg (85); lH NMR (CDCl3) 5.40 (d, 1 H, J 1.2 Hz), 5.03 (d, 1 H, J 1.2 Hz), 3.31 (q, 4 H. J 7.1 Hz), 1.15 (t, 6 H, J 7.1 Hz), 0.18 (s, 9 H); IR (neat) 1710, 1650 cm-1.
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69. We are grateful to NSERC Canada for financial support of our synthetic programs through Operating and Strategic grants.