Ethyl 2-(2-methyl-1,3-dioxolan-2-yl)butanoate → 2-(2-Methyl-[1,3]dioxolan-2-yl)-butan-1-ol

2-(2-Methyl-[1,3]dioxolan-2-yl)-butyric acid ethyl ester (85.5 g) was taken up in dry Et2O (50 mL). This mixture was added dropwise to a suspension of LiAlH4 (16.1 g) in dry Et2O (200 mL), cooled in an ice bath. The mixture was refluxed for 4 h., cooled in an ice bath, and quenched by adding H2O (16.1 mL), 2M aqueous NaOH (32.2 mL) and again H2O (16.1 mL). The suspension was filtered, the filter cake was washed with Et2O, and the combined filtrates were evaporated to dryness. The residue (49 g) was purified by vacuum distillation (112-125° C., 15 mbar), yielding 43.5 g of a clear, colorless liquid. 1H NMR (400 MHz, CDCl3) δ 0.98 (t, J=7.5 Hz, 3H), 1.10-1.24 (m, 1H), 1.31 (s, 3H), 1.50-1.75 (m, 2H), 3.12, (br s, 1H), 3.59-3.76 (m, 2H), 3.94-4.02 (m, 4H).

1. temperaturecooled in an ice bath
2. temperatureThe mixture was refluxed for 4 h.
3. temperaturecooled in an ice bath
4. customquenched
5. additionby adding H2O (16.1 mL), 2M aqueous NaOH (32.2 mL) and again H2O (16.1 mL)
6. filtrationThe suspension was filtered
7. washthe filter cake was washed with Et2O
8. customthe combined filtrates were evaporated to dryness
9. distillationThe residue (49 g) was purified by vacuum distillation (112-125° C., 15 mbar)
10. customyielding 43.5 g of a clear, colorless liquid

ORD-Eintrag

ord-fd14060e71f543e0af53248d9aaabbb7

Quelldatensatz

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08722887B2