1,8-Diazabicyclo(5.4.0)undec-7-ene → (Z)-2,2-Dimethyl-5-(tert-butyldiphenylsilyloxycarbonyl-methylene)-1,3-dioxolan-4-one

Participants

Reaction Conditions

Reaction Steps

A solution of 4-bromo-2,2-dimethyl-5-oxo-1,3-dioxolane-4-acetic acid, tert-butyldiphenylsilyl ester (˜26 g, 52.4 mmol) in dry tetrahydrofuran (160 ml) was cooled to 0° C. and treated dropwise over 5 minutes with 1,8-diazabicyclo [5,4,0]undec-7-ene (12.7 g, 78.8 mmol) and the resulting mixture was stirred at 5° C. for 1.5 hour. The solid formed was filtered and washed with a small amount of tetrahydrofuran. The filtrate was used as such for the next step.

Provenance & Evidence