Triphenylphosphine → 6,7,8-Tris-benzyloxy-5-[2-(4-methoxy-benzyl)-phenoxy]-4-oxa-spiro[2.5]octane

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

(6R,7S,8S)-6,7,8-Tris-benzyloxy-4-oxaspiro[2.5]octan-5-ol (prepared according to an analogous procedure as described in J. Org. Chem. 2002, 67, 3733; Helv. Chim, Acta 1990, 73, 1329; Tetrahedron Lett. 1998, 39, 2021) (220 mg, 0.49 mmol) 2-(4-methoxybenzyl)-phenol (105 mg, 0.49 mmol) and triphenyl phosphine (155 mg, 0.59 mmol) were mixed under argon atmosphere followed by the addition of dry THF. The contents were cooled to 0° C. and DIAD (0.12 ml, 0.59 mmol) was added drop wise. The reaction mixture was refluxed for 12 hours and quenched with 1N dil. HCl (2 mL) and extracted with ethyl acetate (10×3 mL). Organic layer was washed with brine, dried over Na2SO4, concentrated under reduced pressure to give the crude product which was purified by flash column chromatography using 1:4 (Ethyl acetate:Hexane) as eluent to yield 200 mg of 5R,6R,7S,8S)-6,7,8-tris-benzyloxy-5-[2-(4-methoxy-benzyl)-phenoxy]-4-oxa-spiro[2.5]octane.

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