Dimethylformamide → 8-Bromo-9-butyl-9H-purin-6-amine

Reaction equation

[Br:1][C:2]1[NH:10][C:9]2[C:4](=[N:5][CH:6]=[N:7][CH:8]=2)[N:3]=1.Br[CH2:12][CH2:13][CH2:14][CH3:15].C(=O)([O-])[O-].[Cs+].[Cs+].C[N:23](C=O)C>>[Br:1][C:2]1[N:3]([CH2:12][CH2:13][CH2:14][CH3:15])[C:4]2[C:9]([N:10]=1)=[C:8]([NH2:23])[N:7]=[CH:6][N:5]=2

Participants

Reactant 4

HCID 6228Dimethylformamide

HCID 8002Butyl bromide

HCID 10796Cesium carbonate

HCID 218830508-Bromo-7H-purine

Product 1

HCID 116087198-Bromo-9-butyl-9H-purin-6-amineYield 33%

Procedure

8-Bromopurine (2.2 g, 10 mmole) was dissolved in 50 ml of DMF before adding 1-bromo-butane (2.2 ml, 20 mmol) and cesium carbonate (6.7 g, 20 mmol) into the solution. The reaction mixture was left stirring at room temperature for 16 hours before quenching with water and extracting with EtOAc. The organic layer was w ashed with water and dried with MgSO4 before removing solvent under reduced pressure. A white powder (0.9 g, 33%) of 8-Bromo-9-butyl-9H-purin-6-ylamine was isolated using silica gel column chromatography (50% EtOAc/Hexanes). 1H NMR (CDCl3) δ 8.32, (s, 1H), 5.81 (s, 2H), 4.20 (t, 2H), 1.82 (m, 2H), 1.40 (m, 2H), 0.96 (t, 3H). Rf (75% EtOAc/Hex)=0.6.