Chlorotrimethylsilane → HCID 12769232, compound

Participants

Reaction Steps

In a nitrogen stream under stirring, 50 ml of dry tetrahydrofuran is cooled to -78° C. and, then, 20 ml of a solution of 15% n-butyllithium in n-hexane is added thereto. After dropwise addition of 3.66 ml of diisopropylamine, the mixture is stirred at -78° C. for 15 minutes. A solution of 3.1 g of 2,2-dimethyl-1-aza-3-oxabicyclo[4.2.0]octan-8-one in 15 ml of dry tetrahydrofuran is added dropwise and the mixture is stirred at -78° C. for one hour. Then, a solution of 4.34 g of p-toluenesolfonyl azide in 15 ml of dry tetrahydrofuran is added dropwise and the mixture is stirred at -50° C. to -60° C. for 1.5 hours. To this mixture 5.1 ml of trimethylsilyl chloride is added dropwise and the reaction mixture is heated under reflux for 5 hours. Ater cooling, the insolubles are filtered off and the filtrate is concentrated under reduced pressure. The residue is shaken with water and ethyl acetate and the ethyl acetate layer is separated, washed with water, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The solvent is then distilled off and the residue is purified by silica gel column chromatography to give 2,2-dimethyl-7-azido-1-aza-3-oxabicyclo[4.2.0]-octan-8-one as a 1:4 mixture of cis- and trans-isomers.

Provenance & Evidence