Chloride → 2-[[(1-Oxo-1,3-dihydroisobenzofuran-5-yl)carbonyl]amino]-2-methyl-1-propanol

Beteiligte Stoffe

Reaktionsschritte

5-carboxyphthalide (267 g, 1.5 mol) is added to thionyl chloride (950 mL) and then N,N-dimethylformamide (12 mL) is added dropwise. The mixture is heated at reflux for 1 hour and the thionyl chloride is destined off under reduced pressure followed by successive evaporations with toluene (2×50 mL) to give a solid residue. The crude acid chloride is then taken up with 1000 mL of tetrahydrofuran. To a solution of 2-amino-2-methyl-1-propanol (400.5 g, 4.5 mol) in tetrahydrofuran (500 mL), cooled to +5° C. chloride solution is added dropwise whilst maintaining the temperature between +5→+10° C. After the addition is completed, the cooling is removed and the mixture is stirred overnight at ambient temperature. Then the mixture is poured into deionized water (2000 mL) and the organic solvent is removed under reduced pressure at 50° C. After cooling and stirring for 2 hours, the solid product is filtered off and washed with deionized water (2×100 mL). The obtained product is dried at 70° C. for 36 hours under reduced pressure. Yield: 285.3 g (76%) of an off-white product having a purity (HPLC, peak area)=90%. 1H NMR (DMSO d-6, 500 MHz): 1.18 (3H, s), 1.32 (3H, s), 3.55 (2H, s), 5.45 (2H, s), 7.88-7.98 (3H, m), 8.07 (1H, s).

Herkunft & Nachweise