反应详情

温度

0 °C

To a solution of t-butyl alcohol (40.7 g, 549 mmol), Et3N (70 mL, 505 mmol), and DMAP (0.366 mL, 3 mmol) in anhydrous CH2Cl2 (100 mL) at 0° C. was added 2-methyl-butyryl chloride (38 g from step 1). The reaction was stirred at 0° C. for 2 h and then room temperature overnight. The cloudy reaction mixture was filtered through celite and concentrated. The residue was diluted with Et2O and washed with 0.1 N HCl. The organic layer was dried (MgSO4), filtered, and concentrated. The residue was distillated at ˜100° C. bath temperature under weak in-house vacuum twice to give the desired 2-methyl-butyric acid tert-butyl ester 2-2 as a clear oil (42 g, ˜85% purity by 1HNMR analysis). 1HNMR (CDCl3, 500 Hz): 2.28-2.20 (m 1H), 1.68-1.56 (m, 1H), 1.44 (s, 9H), 1.46-1.37 (m, 1H), 1.44 (s, 9H), 1.09 (d, J=7.0 hz, 3H), 0.9 (t, J=7.3 Hz, 3H).

1. customroom temperature overnight
2. customThe cloudy reaction mixture
3. filtrationwas filtered through celite
4. concentrationconcentrated
5. additionThe residue was diluted with Et2O
6. washwashed with 0.1 N HCl
7. dry with materialThe organic layer was dried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated
10. customwas distillated at ˜100° C.