Calcium Carbonate → 5-(Ethoxycarbonylamino)-2-(benzyloxycarbonylamino)phenol

Reaction equation

Cl[C:2]([O:4][CH2:5][CH3:6])=[O:3].[NH2:7][C:8]1[CH:9]=[CH:10][C:11]([NH:15][C:16]([O:18][CH2:19][C:20]2[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=2)=[O:17])=[C:12]([OH:14])[CH:13]=1.C(=O)([O-])[O-].[Ca+2]>O1CCOCC1>[CH2:5]([O:4][C:2]([NH:7][C:8]1[CH:9]=[CH:10][C:11]([NH:15][C:16]([O:18][CH2:19][C:20]2[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=2)=[O:17])=[C:12]([OH:14])[CH:13]=1)=[O:3])[CH3:6]

Participants

Procedure

0.14 mole (15.7 g) of ethyl chloroformate is slowly added dropwise to 0.13 mole (33 g) of 5-amino -2-(benzyloxycarbonylamino)phenol (prepared in Example 1, 2nd stage) and 7.1 g of calcium carbonate in 100 ml of dioxane brought to 80° C. The mixture is heated for a further 20 minutes after the addition is complete. The reaction mixture is filtered while hot in order to remove the inorganic salts. The expected product is precipitated by diluting the cooled filtrate with ice-cold water. When recrystallized from ethyl acetate, it melts at 190° C.