Tetrabutylammonium Fluoride → (S)-tert-butyl 4-(4-(3-(2-chloro-3-fluorobenzyl)-1-methylureido)-5-hydroxypentanoyl)piperazine-1-carboxylate

Participants

Reaction Steps

To a solution of (S)-tert-butyl 4-(5-(tert-butyldimethylsilyloxy)-4-(3-(2-chloro-3-fluorobenzyl)-1-methylureido)pentanoyl)piperazine-1-carboxylate (14 g, 22.8 mmol) in THF (70 mL) was added TBAF (1M, 34.2 mL, 34.2 mmol). The reaction mixture was stirred at RT for 1 h and concentrated. The residue was dissolved in EtOAc (500 mL). The organic mixture was washed with 2% citric acid, NaOH (0.2 N), and brine, dried over Na2SO4, filtered, and concentrated to give (S)-tert-butyl 4-(4-(3-(2-chloro-3-fluorobenzyl)-1-methylureido)-5-hydroxypentanoyl)piperazine-1-carboxylate (12.1 g, crude), which was used without further purification. LRMS (M+H) m/z 501.2.

Provenance & Evidence