반응 #341587

반응 방정식

TMSOTf

3-O-allyl-2,4,6-tri-O-benzoyl-α-D-mannopyranosyl trichloroacetimidate

benzyl 3,4,6-tri-O-benzyl-α-D-mannopyranoside

Et3N

→

tribenzoate

Benzyl 2-O-(3-O-Allyl-2,4,6-tri-O-benzoyl-α-D-mannopyranosyl)-3,4,6-tri-O-benzyl-α-D-mannopyranoside

용매

1,2-DCE

반응 조건

후처리

1. 1
   기타under an atmosphere of argon (30 min)
2. 2
   workup.STIRRINGwith continued stirring (10 min)
3. 3
   여과the mixture was filtered
4. 4
   기타The solvent was evaporated

실험 절차

A mixture of 3-O-allyl-2,4,6-tri-O-benzoyl-α-D-mannopyranosyl trichloroacetimidate [26] (902 mg, 1.21 mmol) and benzyl 3,4,6-tri-O-benzyl-α-D-mannopyranoside [27] (723 mg, 1.34 mmol) in 1,2-DCE (10 mL), was stirred in the presence of mol. sieves (1.0 g of 3 Å powder) under an atmosphere of argon (30 min). The mixture was cooled (0° C.) with continued stirring (10 min) prior to the addition of TMSOTf (219 μL, 1.21 mmol). After some time (10 min), Et3N (100 μL) was introduced and the mixture was filtered. The solvent was evaporated and the residue subjected to FC (10-50% EtOAc/hexane) to yield the tribenzoate (24) as, a colourless oil (1.14 g, 84%). 1H NMR (CDCl3) δ 3.67-3.81, 3.88-3.95, 4.06-4.15, 4.30-4.35 (4 m, 12H; H-2I,-3I,-4I,-5I,-6aI,-6bI,-3II,-5II,-6aII,-6bII, OCH2), 4.94-4.70 (m, 7H; CH2Ph), 4.84 (d, 1H, JA,B 10.8 Hz; A of AB quartet), 4.93-4.96, 5.04-5.09 (2 m, 2H; ═CH2), 5.02 (d, 1H, J1,2 1.9 Hz; H-1I), 5.24 (d, 1H; J1,2 1.9 Ha; H-1II), 5.59-5.69 (m, 1H; ═CH), 5.72 (dd, 1H, J2,3 3.1 Hz; H-2II), 5.75 (dd, 1H, J3,4 9.8, J4,5 9.9 Hz; H-4II), 7.09-7.58, 7.97-8.06 (2 m, 35H; Ar). 13C NMR (CDCl3) δ 61.50, 63.49 (2 C; C-6I,-6II), 68.63, 69.17, 69.31, 69.46, 69.64, 71.08, 72.04, 72.64, 73.60, 74.73, 75.30, 75.38 (13 C; C-3I,-4I,-5I,-2II,-3II,-4II,-5II, OCH2, CH2Ph), 79.97 (C-2I), 98.52, 99.60 (C-1I,-1II), 117.67 (═CH2), 127.70-138.43 (43 C; ═CH, Ar), 165.61, 165.69, 166.42 (3 C; C═O).

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