Hydrochloric Acid → 1,2-Cyclopropanedicarboxylic acid, trans-

Diethyl carboxylate 3 (16.9 g, 19.3 mmol) was dissolved in 170 ml of 2N NaOH and heated under reflux for 1 h. The solution was stirred for additional 18 h at 22° C. The solution was cooled, adjusted to pH 3 with 2N HCl, saturated with NaCl, and finally extracted with ethyl acetate (2×100 ml). The pooled extracts were dried (Na2SO4), evaporated to dryness, and the white residue was used for the next step without further purification (8.5 g, 79%); mp 175–176° C. 1H-NMR (D2O): δ 1.42 (m, 2H), 2.18 (m, 4H).

1. temperatureheated
2. temperatureunder reflux for 1 h
3. temperatureThe solution was cooled
4. extractionfinally extracted with ethyl acetate (2×100 ml)
5. dry with materialThe pooled extracts were dried (Na2SO4)
6. customevaporated to dryness
7. customthe white residue was used for the next step without further purification (8.5 g, 79%)

ORD-Eintrag

ord-eafa451b143c4798beed215005a9e1bc

Quelldatensatz

uspto-grants-2007_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07235695B2