Ethoxytrimethylsilane → tert-Butyl 4-methylene-1-oxa-9-azaspiro[5.5]undecane-9-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 1-Boc-piperidone (2.39 g, 12 mmol) and ethoxytrimethylsilane (3.75 mL, 24 mmol) in 80 mL of CCl4 under stirring at 0° C. was added trimethylsilyl trifluoromethylsulfonate (217 μL, 1.2 mmol) and trimethyl-(2-methylene-4-trimethylsilyloxybutyl)silane (E. I. Marko et al., Journal of Organic Chemistry 1992, 57, 2211-2213) dissolved in in 23 mL of CCl4. After stirring at 0-5° C. for 6 h and overnight resting at 0° C., the reaction mixture was washed with water, dried on Na2SO4, filtered and the solvent was evaporated to dryness in vacuo. The residual 6.5 g of colourless oil was purified by means of automated flash chromatography (SP1®TM-Biotage; Petroleum Ether-EtOAc gradient from 99:1 to 85:15) to give 3.2 g of the title compound as colourless oil. Yield: 1000%

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