ORGN 637 |
| We have recently described a palladium-catalyzed, [3,3]-sigmatropic rearrangement of (allyloxy)iminodiazaphospholidines 1a/b, thermodynamically driven by a P=N to P=O interconversion. With 5% PdCl2(MeCN)2 at room temperature, the resultant phosphoramides 2a/b were obtained in high yields and were readily hydrolyzed under mild, acidic conditions to yield allylic amines 3a and tosylamines 3b. In continuing studies, we have investigated the use of chiral auxiliaries and chiral palladium catalysts in the asymmetric rearrangement of these substrates. Utilization of the chiral palladacycle 4 allowed for the rearrangement to proceed with enantioselectivities upwards of 95%. The development, scope and limitations of this asymmetric transposition will be described.
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Metal-Mediated Reactions and Syntheses
8:00 AM-12:00 PM, Wednesday, 16 March 2005 Convention Center -- Room 10, Oral
Division of Organic Chemistry |
