تفاعل #162044

معادلة التفاعل

O(Et)2

BF3

D-glucose peracetate

8-pentadecanol

→

glycoside

المردود 100.1%

8-Pentadecanyl 2,3,4,6-tetra-O-acetyl-D-glucopyranoside

المردود 100.1%

المذيبات

DCE

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONbefore pouring onto short plug of silica
2. 2
   غسيلeluting with EtOAc
3. 3
   أخرىThe solvent was evaporated before the crude material
4. 4
   أخرىwas purified by column chromatography (SiO2
5. 5
   غسيلloaded with DCM, elution with DCM (100 mL)

الإجراء التجريبي

To a solution of D-glucose peracetate (250 mg, 640 μmol) in DCE (1 mL) was added 8-pentadecanol (220 mg, 960 μmol). BF3.O(Et)2 (134 μL, 1.1 mmol) was added and the mixture stirred at room temperature overnight before pouring onto short plug of silica and eluting with EtOAc. The solvent was evaporated before the crude material was purified by column chromatography (SiO2, loaded with DCM, elution with DCM (100 mL), then 20% EtOAc/Hexane to 35% EtOAc/Hexane) to give the glycoside 141 as a white solid (179 mg, 50%). 1H NMR (CDCl3, 400 MHz) δ: 5.19 (dd, 1H, J2,3=9.5, J3,4=0.0, H-3), 5.06 (dd, 1H, J4,5=9.7, H-4), 4.96 (dd, 1H, J1,2=8.0, J2,3=9.6, H-2), 4.52 (d, 1H, H-1), 4.21 (dd, 1H, J5,6b=5.2, J6a,6b=12.1, H-6b), 4.12 (dd, 1H, J5,6a=2.6, H-6a), 3.66 (ddd, 1H, J4,5=10.0, H-5), 3.53 (m, 1H, CH2CHOCH2), 2.07 (s, 3H, OCOCH3), 2.02 (s, 6H, OCOCH3), 2.00 (s, 3H, OCOCH3), 1.60-1.20 (m, ˜24H, CH2), 0.88 (t, 3H, J=7.0, CH3), 0.87 (t, 31-1, J=7.0, CH3).

المصدر