1999 stereochemistry

stereochemistry (general, optical resolution)O 0030

38 - 044Sparteine-Mediated Enantioselective [2,3]-Wittig Rearrangementof Allyl ortho-Substituted Benzyl Ethers and ortho-SubstitutedBenzyl Prenyl Ethers. — Allyloxybenzamides (I), (IV), and (VI) ando-substituted benzyl prenyl ethers (VIII) and (X) are investigated in the titlerearrangement reaction. The poor solubility of isopropylamide (VI) leads toonly low yield but the highest enantioselectivity. For dialkylamides (I) and (IV)opposite enantioselectivities are obtained. The introduction of several functionalgroups other than carbamoyl does not enhance the enantioselectivities. —(KAWASAKI, TAKESHI; KIMACHI, TETSUTARO; Tetrahedron 55 (1999) 22,6847-6862; Grad. Sch. Pharm. Sci., Kyoto Univ., Sakyo, Kyoto 606, Japan; EN)

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