Dicyclohexylcarbodiimide → Retinamide

Reaction equation

C1([N:7]=C=NC2CCCCC2)CCCCC1.[CH3:16][C:17]1[CH2:22][CH2:21][CH2:20][C:19]([CH3:24])([CH3:23])[C:18]=1/[CH:25]=[CH:26]/[C:27](/[CH3:37])=[CH:28]/[CH:29]=[CH:30]/[C:31](/[CH3:36])=[CH:32]/[C:33](O)=[O:34].ON1C2C=CC=CC=2N=N1>ClCCl>[CH3:16][C:17]1[CH2:22][CH2:21][CH2:20][C:19]([CH3:24])([CH3:23])[C:18]=1/[CH:25]=[CH:26]/[C:27](/[CH3:37])=[CH:28]/[CH:29]=[CH:30]/[C:31](/[CH3:36])=[CH:32]/[C:33]([NH2:7])=[O:34]

Participants

Procedure

3.41 g (0.0165 mole) of dicyclohexylcarbodiimide (DCC) was added to 50 ml of dry dichloromethane solution of 6.98 g (0.0126 mole) of 1-amino-polyethyleneglycol-monomethyl ether (formula (IIIa), mean molecular weight 550), 4.54 g (0.0151 mole) of retinoic acid and 1.7 g (0.0126 mole) of 1-hydroxybenzotriazole and then stilled at room temperature for 8 hours in nitrogen atmosphere under shading and anhydrous condition. The reaction solution was filtered and then the solvent was removed by distillation under reduced pressure. The residue was separated by column chromatography (SiO2, mesh size 270-400, dichloromethane/methanol=15:1, v/v) to obtain 9.42 g (Yield 75%) of the title compound (pale yellow liquid in the form of wax, Tm=−15° C., Rf=0.22).