Metalations utilizing aryllithiums; ortho-functionalization of p-bromoanisole (pBrA)

Tetrahedron Letters

Volumn 50, Issue 14, 2009, Pages 1593-1595

  Slocum, D W ^a   Reece, Troy L ^a   Sandlin, Rebecca D ^a   Reinscheld, Thomas K ^a   Whitley, Paul E ^a  

^a WESTERN KENTUCKY UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BROMINE DERIVATIVE; LITHIUM; METAL;

ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; DERIVATIZATION; METHODOLOGY;

EID: 60249099361     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2009.01.104     Document Type: Article

References (17)

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10. Wittig G., Pockels U., and Droge H. Chem. Ber. 71 (1938) 1903
11. 2O) in n-hexane with no catalyst, heated at 60 °C for 4-6 h.
12. a value of 43 to benzene.
13. A reproducible 25% loss of DMA accrues from the combined effects of incomplete metalation, o-LiDMA solubility in hydrocarbon solvent and the two transfers necessary for the two washings with cold hexanes.
14. Eaborn C., and Walton D.R.M. J. Organomet. Chem. 3 (1964) 169
15. If the washing purification procedure is omitted, biphenyl formation via benzyne intermediate production is increased. Even with these washings about 2% of biphenyl contaminants can be detected. This is likely due to the lingering amounts of TMEDA bringing about an increase in the basicity of the remaining o-LiDMA.
16. 13C NMR δ 21.9, 25.8, 36.5, 55.7, 73.0, 113.2, 113.8, 129.1, 130.5, 138.8, 156.4.
17. Oddershede J., Henriksen L., and Larsen S. Org. Biomol. Chem. 1 (2003) 1053 We have no explanation for the discrepancy in mp's of the two samples. The published NMR and the NMR we have obtained appear identical