Dichloromethane → HCID 59013467, compound

Participants

Reaction Steps

O3 was bubbled into a cooled solution (−78° C.) of (1S,3′R,4′S,5′R,6′R)-3-allyl-3′,4′,5′-tris(benzyloxy)-6′-(benzyloxymethyl)-5-chloro-6-(4-ethylbenzyl)-2,3,3′,4′,5′,6′-hexahydrospiro[indene-1,2′-pyran] (100 mg, 0.12 mmol) in CH2Cl2 (20 mL). After 5 min, N2 was bubbled into this solution for 20 min while the reaction temperature was gradually raised to room temperature. PPh3 (50 mg, 0.24 mmol) was added and the resulting mixture was stirred for 1 h at room temperature and concentrated. The resulting crude aldehyde was dissolved in THF (20 mL), and NaBH4 (9 mg, 0.24 mmol) was added. After being stirred at room temperature for 2 h, the reaction mixture was quenched by saturated aqueous NH4Cl solution and concentrated. The residue was partitioned between water and AcOEt, the organic layer was separated, washed with brine and dried over Na2SO4. Concentration and purification by preparative HPLC gave 85 mg (95%) of tetra-benzyl-protected alcohol, which was deprotected using the standard hydrogenation procedure to provide the title compound (30 mg). 1H NMR (CD3OD, 300 MHz) δ 7.26 (s, 1H), 7.24 (s, 1H), 7.09 (m, 4H), 4.05 (s, 2H), 3.82-3.21 (m, 9H), 2.77 (dd, J=12.9, 7.8 Hz, 1H), 2.58 (q, J=7.8 Hz, 2H), 2.13 (m, 1H), 1.77 (dd, J=12.9, 7.8 Hz, 1H), 1.68 (m, 1H), 1.19 (t, J=7.8 Hz, 3H); MS ESI (m/z) 463 (M+1)+, calc. 460.

Provenance & Evidence