تفاعل #2336541

معادلة التفاعل

Ac2O

KCN

benzaldehyde

2,6-lutidine

water

→

O-Acetyl (S)-mandelonitrile

المذيبات

CH2Cl2

ظروف التفاعل

المعالجة

1. 1
   ترشيحfiltered
2. 2
   workup.ADDITIONpassed through a SiO2 column (1 cm×10 cm) in a mixture of hexane/AcOEt 10:1
3. 3
   أخرىto remove the catalyst
4. 4
   أخرىThe filtrate was evaporated
5. 5
   workup.DISTILLATIONdistilled in vacuo

الإجراء التجريبي

To a mixture of KCN (5.0 g, 77 mmol) and catalyst 1a (R1=R2=tBu)(0.3 g, 0.25 mmol) in CH2Cl2 (60 ml) were added with stirring benzaldehyde (2.5 ml, 25 mmol), 2,6-lutidine (0.28 ml, 2.4 mmol) and water (0.4 ml, 24 mmol). The reaction mixture was cooled to −30° C. and Ac2O (5 ml, 53 mmol) was added. The reaction mixture was stirred for 10 hours at −30° C. and then filtered, passed through a SiO2 column (1 cm×10 cm) in a mixture of hexane/AcOEt 10:1 to remove the catalyst. The filtrate was evaporated and distilled in vacuo to give 2.7 g (63%) of O-Acetyl (S)-mandelonitrile with 87% enantiomeric excess as determined by chiral gas chromatography.

المصدر