Abstract
A new uncatalyzed method for the preparation of cyanohydrin O-alkyl ethers was developed using the high-pressure-promoted reaction of acetals
with trimethylsilyl cyanide in nitromethane.
Key words
cyanation - acetals - trimethylsilyl cyanide - nitromethane - high pressure reaction
References and Notes
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General Procedure.
A mixture of acetal (1.0 mmol) and TMSCN (1.2 mmol) in MeNO2 (ca. 1.2 mL) was placed in a Teflon reaction vessel, and the mixture was allowed
to react at 0.8 GPa at the appropriate temperature for the specified time (Table
[2]
). After the mixture was cooled and the pressure was released, the mixture was concentrated
in vacuo. The crude product was purified by silica gel column chromatography (elution
with hexane-EtOAc) to afford the pure product in good to excellent yields.
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Consistent with this expectation, benzaldehyde diacetyl acetal was also unreactive
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