1998 benzofuran derivatives

benzofuran derivativesR 0070

27 - 124Stereoselective Indium-Promoted Allylation of γ-Hydroxy-γ-lactonesunder Aqueous Conditions. The Neighboring Carboxyl Effect. —In the presence of In the hydroxylactones (I) and (IVa) undergo allylationwith high diastereoselectivity, a result presumably due to internal chelation tothe neighboring carboxyl group. The diastereoselectivity can be increased byaddition of Bu4NBr. Interestingly, the free hydroxy derivative (IVb) exhibitslow diastereoselectivity due to additional chelation to the hydroxy group. —(BERNARDELLI, P.; PAQUETTE, L. A.; J. Org. Chem. 62 (1997) 24,8284-8285; Evans Chem. Lab., Ohio State Univ., Columbus, OH 43210, USA;EN)

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