Reaktion #1934286

Reaktionsgleichung

xylitol

2,2-dimethoxypropane

p-toluenesulfonic acid monohydrate

→

Diisopropylidenexylitol

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeIn a 5 L round-bottom flask fitted with a thermometer
2. 2
   workup.ADDITIONa nitrogen-introducing tube, and a stirrer
3. 3
   Sonstigewas carried out at 65° C
4. 4
   SonstigeThe solvent of the reaction solution was removed by distillation and purification by distillation (b.p. 108° C./0.15 mmHg)
5. 5
   Sonstigeto obtain

Vorschrift

In a 5 L round-bottom flask fitted with a thermometer, a nitrogen-introducing tube, and a stirrer were placed 1000 g of xylitol, 1916 g of 2,2-dimethoxypropane, and 37.5 mg of p-toluenesulfonic acid monohydrate and, with introduction of nitrogen thereinto, the reaction was carried out at 65° C. The solvent of the reaction solution was removed by distillation and purification by distillation (b.p. 108° C./0.15 mmHg) was performed to obtain an isomer mixture of 1,2,3,4-diisopropylidenexylitol (formula (5)) and 1,2,4,5-diisopropylidenexylitol (formula (6)). 1H-NMR (CDCl3, internal standard TMS) δ (ppm): 1.37-1.44 (12H, m, —C(CH3)2), 3.59-3.65 (1H, m, —CH—O—), 3.81-3.90 (2H, m, —CH2—O—), 3.98-4.01 (1H, m, —CH—O—), 4.04-4.10 (2H, m, —CH2—O—), 4.11-4.23 (1H, m, —CH—O—) 1H, m, —CH—O—)

Quelle