(-)DIP-Chloride → (S)-4-[(4-bromophenyl)-hydroxymethyl]-piperidine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsschritte

To a solution of (−)-DIP-chloride™ (6.42 g, 20.0 mmol) in THF (10 mL) at 0° C. was added 4-(4-bromobenzoyl)-piperidine-1-carboxylic acid tert-butyl ester (3.68 g, 10.0 mmol). The mixture was stirred at room temperature for 29 hours. Aqueous work-up and purification gave (S)-4-[(4-bromophenyl)-hydroxymethyl]-piperidine-1-carboxylic acid tert-butyl ester (ee 78% determined by both chiral HPLC and Mosher ester) as a crystalline solid (2.22 g, 54%). This material was recrystallized (CH2Cl2/hexane) three times to provide (S)-4-[(4-bromophenyl)-hydroxymethyl]-piperidine-1-carboxylic acid tert-butyl ester as a white solid (1.29 g, 35%) with ee of 96%.

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