ORGN 129 |
| Decarboxylative allylic etherification of allyl aryl carbonate 1 was studied. A combination of Ir(I), phosphoramidite ligand and DBU was shown to be necessary for catalysis. The etherification reactions generally proceeded with good to excellent regio- and enatioselectivities to afford the branched 1-(aryl/alkyl)-1-aryloxyprop-2-ene 2 in high reaction yields. The reaction yield and regioselectivity were dependent on the substituent (R1) of the aryl ring: electron donating groups gave better reaction yield and regioselectivity than electron withdrawing groups. The scope and mechanism of the reactions will be described. Also presented is the asymmetric synthesis of a naturally occurring chroman, Tephrowastin E, which utilizes the developed etherification reaction as well as ring closing metathesis reaction as key reactions.
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Asymmetric Reactions and Syntheses, Metal-Mediated Reactions, Combinatorial, Parallel, and Solid-Phase Chemistry
8:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Organic Chemistry |
