Hydrochloric Acid → (S)-methyl 2-((tert-butoxycarbonyl)amino)-3-(5-chlorothiophene-2-carboxamido)propanoate

Beteiligte Stoffe

Reaktionsschritte

Commercially available (S)-3-amino-2-tert-butoxycarbonylamino-propionic acid (BOC-Dap-OH) (18.09 g, 88.56 mmol) was suspended in 100 ml DCM with N-hydroxy-succinimide (16.99 g, 147.61 mmol) and N,N′-diisopropylcarbodiimide (11.43 ml, 73.8 mmol), then 5-Chloro-thiophene-2-carboxylic acid (12 g, 73.8 mmol) and DIPEA (25.51 ml, 147.61 mmol) in 60 ml DCM were slowly added. The mixture was stirred at RT for 2 h, then cooled to 0° C. and TMS-diazomethane was slowly added. The reaction was stirred for 2 h at RT, HCl solution (0.5 M) was added and the organic layer was separated, washed with H2O, dried with Na2SO4, filtered and evaporated to dryness. The resulting solid was triturated 16 h with diisopropyl ether, filtered and washed with diisopropyl ether and dried under vacuum at 60° C. 24.4 g of crude product were obtained and used without further purification.

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