Ammonia → 10-Acetamido-10-(3-chlorophenyl)-2,3,4,10-tetrahydropyrimido[1,2-a]indole

Reaction equation

S(=O)(=O)(O)[OH:2].[Cl:6][C:7]1[CH:8]=[C:9]([C:13]2(O)[C:21]3[CH:20]=[CH:19][CH:18]=[CH:17][C:16]=3[N:15]3[CH2:22][CH2:23][CH2:24][N:25]=[C:14]23)[CH:10]=[CH:11][CH:12]=1.N.[C:28](#[N:30])[CH3:29]>>[C:28]([NH:30][C:13]1([C:9]2[CH:10]=[CH:11][CH:12]=[C:7]([Cl:6])[CH:8]=2)[C:21]2[CH:20]=[CH:19][CH:18]=[CH:17][C:16]=2[N:15]2[CH2:22][CH2:23][CH2:24][N:25]=[C:14]12)(=[O:2])[CH3:29]

Participants

Reactant 4

HCID 222Ammonia

HCID 1118Sulfuric Acid

HCID 6342Acetonitrile

HCID 37825Ciclazindol

Product 1

HCID 1574477710-Acetamido-10-(3-chlorophenyl)-2,3,4,10-tetrahydropyrimido[1,2-a]indole

Procedure

Concentrated sulphuric acid (12 ml) was added dropwise over 5 minutes to vigorously stirred acetonitrile (24 ml) at 0°-5°. The resulting colourless solution was treated in one portion with 10-(3-chlorophenyl)-2,3,4,10-tetrahydropyrimido[1,2-a]indol -10-ol (3.0 g). The mixture was immediately stirred and heated at 50°-60° whereupon solution occurred within 5 minutes. After 1 hour, the solution was poured onto ice (100 ml) and the mixture was basified with saturated aqueous ammonia (90 ml) and extracted with dichloromethane (3×60 ml). The extracts were dried (MgSO4) and evaporated in vacuo. The residue was triturated with ethyl acetate to give light brown crystals which were purified by flash chromatography (Al2O3, ethyl acetate), trituration with ethanol-ether (1:1), and washing with ether to give the title compound free base as a colourless powder.