[CH:1]1[C:13]2[CH:12]([CH2:14][O:15][C:16]([N:18]3[CH2:23][CH2:22][CH:21]([C:24]([OH:26])=O)[CH2:20][CH2:19]3)=[O:17])[C:11]3[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=3)[C:5]=2[CH:4]=[CH:3][CH:2]=1.CN(C=O)C.C(Cl)(=O)C([Cl:35])=O>C(Cl)Cl>[Cl:35][C:24]([CH:21]1[CH2:22][CH2:23][N:18]([C:16]([O:15][CH2:14][CH:12]2[C:11]3[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=3[C:5]3[C:13]2=[CH:1][CH:2]=[CH:3][CH:4]=3)=[O:17])[CH2:19][CH2:20]1)=[O:26]To a stirred solution of piperidine-1,4-dicarboxylic acid mono-(9H-fluoren-9-ylmethyl) ester (5 g, 14.2 mmol) in CH2Cl2 (50 mL) was added DMF (0.5 mL) and the resulting solution was cooled to 0° C. To this solution oxalyl chloride (3.6 g, 28.44 mmol) was added dropwise and the reaction mixture was stirred at RT for 16 h. The reaction mixture was concentrated under reduced pressure to afford (9H-fluoren-9-yl)methyl 4-(chlorocarbonyl)-piperidine-1-carboxylate (5 g, 95%) as brown liquid.
Wird geladen…