2,4,6-Trimethylpyridine → 2-(1-(Tert-butyldimethylsilyloxy)cyclopent-3-enyl)acetaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

1-(2,2-dimethoxyethyl)cyclopent-3-enol (13.5 g, 78 mmol) was dissolved in DCM (250 mL). This was chilled to 0° C. under nitrogen and 2,4,6-trimethylpyridine (42 mL, 314 mmol) was added dropwise over 10 minutes. Tert-butyldimethylsilyl trifluoromethanesulfonate (18 mL, 78 mmol) was added dropwise via syringe very slowly over 20 minutes keeping the internal temperature below 5° C. The reaction was allowed to come to RT. By TLC (20% EtOAc/hexanes; KMnO4 stain), the starting material was completely consumed (˜2 hours). The reaction was then chilled back to 0° C. and triethylsilyl trifluoromethanesulfonate (35 mL, 157 mmol) was added in dropwise over a 10 minute period. This was allowed to stir at 0° C. for 1 hour before adding water (250 mL). The ice bath was removed and this mixture was stirred vigorously for ˜18 hours. The reaction was poured into a seperatory funnel and the DCM layer was separated. The organic was washed with dilute aqueous HCl, brine, dried over sodium sulfate, filtered and concentrated to afford a yellow oil which was flashed on silica by gradient eluting with hexanes to 20% EtOAc/hexanes over a 40 minute period. Product fractions were combined to afford the title compound.

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