Short-RInChIKey=SA-FUHFF-UHFFFADPSC-GLVNZYODMK-UHFFFADPSC-NUHFF-NSOPS-NUHFF-ZZZ

The reaction was performed under inert atmosphere using Schlenk techniques. Methyl levulinate (3.99 g, 3.80 mL, 30.7 mmol, 1.0 equiv) was dissolved in dry chloroform (10 mL) and cooled to 0 °C. A solution of bromine (1.80 mL, 35.1 mmol, 1.1 equiv.) in dry chloroform (6 mL) was added dropwise. The mixture was stirred 0 °C for 1 h, allowed to warm to room temperature and stirred for 30 min until the solution turned from brown to light yellow. Excess hydrogen bromide was removed in vacuo. A solution of triethylamine (10.2 g, 14.0 mL, 100 mmol, 3.3 equiv.) in dry chloroform (20 mL) was slowly added and the reaction mixture was stirred for 30 min. The reaction mixture was washed with water (2 x 40 mL), hydrochloric acid (2 M, 2 x 40 mL), saturated sodium carbonate solution (2 x 40 mL) and brine (40 mL). The organic phase was carefully concentrated in vacuo (not under 300 mbar). The resulting brown liquid was distilled at 130 °C (stepwise, 10 °C) under vacuum (8-11 mbar) and the product collected at a cold trap (see pictures in analyses) affording the product (1.72 g, 13.4 mmol, 44%) as colorless crystals.