Diisopropylcarbodiimide → 3-(2-Biphenyl-4-yl-ethylcarbamoyl)-2-phenethyl-pentanedioic acid 5-tertbutyl ester 1-methyl ester

Participants

Reaction Steps

A solution of the compound of example 53 (590 mg, 1.68 mmol) and HOBt (272 mg, 2.016 mmol) in anhydrous DMF was stirred in an ice bath for 10 minutes. Biphenyl ethylamine (404 mg, 2.02 mmol) was added followed by the addition of DIC (320 μL, 2.01 mmol). After 20 minutes, the ice bath was removed and stirring was continued at room temperature. After 24 h of stirring, the reaction mixture was partitioned between ethyl acetate and HCl (1M, excess). The aqueous phase was extracted several times with ethyl acetate. The recombined organic layer was extracted with brine, saturated sodium hydrogen carbonate, and brine. The solvent was evaporated following drying over sodium sulfate and filtration. The crude was flashed using 25% EtOAc in hexanes. 1H-NMR(CDCl3, 300 MH: 1.41(s, 9H); 1.82(m, 2H); 2.23(m, 1H); 2.55(t, J=8.1 Hz, 2H); 2.75(m, 5H); 3.54(m, 1H); 3.70(s, 3H); 6.09(t, J=5.7 Hz, 1H); 7.13–7.36, 7.41–7.49, 7.55–7.58(m, 14H).

Provenance & Evidence