反应详情

To a solution of 2.01 g (23.9 mmol) of 2-butynoic acid and 2.9 mL (22.3 mmol) isobutyl chloroformate in 30 mL tetrahydrofuran was stirred at 0° C. under nitrogen as 2.42 g (2.63 mL, 22.3 mmol) of N-methyl morpholine was added over 3 min. After stirring for 15 min., a solution of N′-(4-amino-2-cyanophenyl)-N,N-dimethylformamidine and 1.6 g (1.75 mL, 15.9 mmol) of N-methyl morpholine in 25 mL tetrahydrofuran was added over 4 min. The mixture was stirred 30 min. at 0° C. and 30 min. at room temperature. The mixture was diluted with 70 mL of ethyl acetate and poured into a mixture of brine and saturated sodium bicarbonate. The organic layer was dried (MgSO4) and filtered through a pad of silica gel. The solvent was removed and the residue was stirred with 50 mL of ether. The suspended solid was collected to give 3.61 g (89%) of an off-white solid. mass spectrum (m/e): 255.0 (M+H, electrospray).

1. additionwas added over 3 min
2. stirringThe mixture was stirred 30 min. at 0° C. and 30 min. at room temperature
3. dry with materialThe organic layer was dried (MgSO4)
4. filtrationfiltered through a pad of silica gel
5. customThe solvent was removed
6. stirringthe residue was stirred with 50 mL of ether
7. customThe suspended solid was collected