Water → Methyl 1,4-dioxane-2-carboxylate

Temperatur

5 °C

A solution of [1,4]dioxane-2-carboxylic acid (supplied by Enamine Ltd.), (2.90 g, 22.0 mmol) in N,N-dimethylformamide (15 mL) was stirred at room temperature. Potassium carbonate (6.07 g, 44.0 mmol) was added and the suspension was stirred at 5° C. Iodomethane (6.25 g, 2.75 mL, 44.0 mmol) was added dropwise and the reaction mixture was stirred at room temperature for 24 h. Water and brine were added and the mixture was extracted with diethyl ether. The aqueous layer was saturated with sodium chloride and the mixture was extracted with ethyl acetate (3×). The organic extracts were combined, dried over anhydrous magnesium sulfate, filtered and evaporated. The residue was purified by silica gel chromatography using a gradient of pentane/diethyl ether 4:1 to 1:1 to afford the title compound (3.06 g, 95%) as a volatile, pale yellow oil. 1H NMR (300 MHz, CDCl3) δ 3.68-3.78 (m, 4H), 3.81 (s, 3H), 3.97-4.05 (m, 2H), 4.29 (dd, J=8.5, 3.1 Hz, 1H). LCMS (m/z) 169.2 [M+Na], Tr=0.69 min.

1. stirringthe reaction mixture was stirred at room temperature for 24 h
2. extractionthe mixture was extracted with diethyl ether
3. extractionthe mixture was extracted with ethyl acetate (3×)
4. dry with materialdried over anhydrous magnesium sulfate
5. filtrationfiltered
6. customevaporated
7. customThe residue was purified by silica gel chromatography

ORD-Eintrag

ord-63a58cfc0f3f403791888822d3e7ff37

Quelldatensatz

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09062092B2