ORGN 93 |
| David S. Surry and David R. Spring. Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom |
| The oxidation of organocuprates is known to be an effective means of generating biaryl bonds. We have succeeded in improving the functional group tolerance of this reaction by making these cuprates from the corresponding aryl Grignard reagents, themselves formed by a halogen-magnesium exchange. We have also found that the required cuprates can be created by a transmetallation from organolithiums generated by an ortho-lithiation. The use of such conditions allows biaryls which possess four ortho substituents to be synthesised efficiently. Furthermore, the use of a chiral oxazoline to direct the ortho-lithiation allows the biaryl axis to be formed with excellent diastereoselectivity. In addition, intramolecular reactions allow the construction of biaryl-containing medium ring compounds. This methodology is being applied to natural product synthesis. |
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New Reactions and Methodology, Metal-Mediated Reactions, Heterocycles and Aromatics
8:00 PM-10:00 PM, Sunday, March 28, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Organic Chemistry |
