Diethyl Ether → HCID 13407681, compound

Temperature

-78 °C

2.02 g of magnesium and 30 mL of ethyl ether were charged to a 100 mL three-neck round bottom flask to which 6.3 g of 2-chloropropane was then gradually added to prepare a Grignard solution. 10.7 g of titanium (IV) isopropoxide and 3.7 g of vinyltrimethylsilane were added to another 100 mL three-neck round bottom flask cooled to −78° C., and the above-prepared Grignard solution was gradually added thereto over 30 min. The thus-prepared reaction solution was warmed to −50° C. and vigorously stirred for 2 hours. The reaction solution was maintained at −50° C. while 3.5 g of ethyl acetate was gradually added over 30 min. The reaction solution was warmed to −20° C., vigorously stirred for 1 hour, warmed to 0° C. and then vigorously stirred for another 1 hour. The reaction solution was warmed to room temperature and 7 mL of saturated brine was added to the solution. The resulting solution was filtered through Celite which was then thoroughly washed once more with 20 mLL of ether. The thus-obtained filtrate was dried over anhydrous magnesium sulfate (MgSO4), and was concentrated by the evaporation of solvent under low vacuum at a low temperature of less than 30° C. The resulting concentrate was distilled (35-50° C./0.1 mmHg) to thereby give 2.2 g of 1-methyl-1-hydroxy-2-(trimethylsilyl)cyclopropane as a mixture of two isomers, i.e. trans and cis isomers in a ratio of 3 to 5:1. Results of 1H-NMR and 13C-NMR for the major isomer (trans isomer) of the mixture are given below.

1. additionwas then gradually added
2. customto prepare a Grignard solution
3. additionthe above-prepared Grignard solution was gradually added
4. customThe thus-prepared reaction solution
5. temperaturewas warmed to −50° C.
6. additionwas gradually added over 30 min
7. temperatureThe reaction solution was warmed to −20° C.
8. stirringvigorously stirred for 1 hour
9. temperaturewarmed to 0° C.
10. stirringvigorously stirred for another 1 hour
11. temperatureThe reaction solution was warmed to room temperature
12. filtrationThe resulting solution was filtered through Celite which
13. washwas then thoroughly washed once more with 20 mLL of ether
14. dry with materialThe thus-obtained filtrate was dried over anhydrous magnesium sulfate (MgSO4)
15. concentrationwas concentrated by the evaporation of solvent under low vacuum at a low temperature of less than 30° C
16. concentrationThe resulting concentrate
17. distillationwas distilled (35-50° C./0.1 mmHg)

ORD record

ord-7d0f1ee9d0774847a318b094b8f08fe0

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08163244B2