9-Fluorenylmethyl chloroformate → methyl (2R)-2-({[(9H-fluoren-9-yl)methoxy]carbonyl}amino)-2-(4-hydroxyphenyl)acetate

Beteiligte Stoffe

Reaktionsschritte

To a 0° solution of 2.50 g (11.48 mmol) of amino-(4-hydroxy-phenyl)-acetic acid methyl ester (from Example 178) in 125 mL of dichloromethane was added 10 mL of N,N-diisopropylethylamine followed by 2.97 g (11.48 mmol) of 9-fluorenylmethyl chlorformate and the resulting mixture was stirred at 0° for 2 h and room temperature for 2 h. The reaction mixture was then concentrated and the residue was diluted with ethyl acetate and water. The organics were washed with water, dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:3) to provide methyl(2R)-{[(9H-fluoren-9-ylmethoxy)carbonyl]amino}(4-hydroxyphenyl)ethanoate as a white solid. Electrospray Mass Spec 404.1 (M+H)+.

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