反应详情

温度

-78 °C

0.86 g (2.3 mmol) of tert-butyl 5-[2-(dichloromethyl)-4(RS),5,5-trimethyl-1,3,2-dioxaborolan-4-yl]-3(RS)-methylvalerate was dissolved in 5 ml of tetrahydrofuran and the solution was cooled to −78° C. under a nitrogen atmosphere. 2.6 ml (2.6 mmol) of 1M ethylmagnesium bromide in tetrahydrofuran were added dropwise, the resulting solution was stirred for 16 hours while slowly warming to room temperature and then diluted with ethyl acetate and extracted with 2M hydrochloric acid and brine. The organic phase was dried over sodium sulphate and then evporated under a vacuum to give 0.83 g of tert-butyl 5-[2-(1(RS)-chloropropyl)-4(RS),5 ,5-trimethyl-1,3 ,2-dioxaborolan-4-yl]-3(RS)-methylvalerate as an oil which was used in the next step without purification.

1. temperaturewhile slowly warming to room temperature
2. extractionextracted with 2M hydrochloric acid and brine
3. dry with materialThe organic phase was dried over sodium sulphate