3-(4-bromophenyl)propanal

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: According to the general procedure (GP10), microwave-assisted Pictet-Spengler reaction (60 W; 140° C.; 6.5 bars; 10 min.) between 2-(2-ethyl-4-iodo-imidazol-1-yl)-ethylamine (26.610 mmol) and 3-(4-bromo-phenyl)-propionaldehyde (6.350 g; 29.803 mmol) afforded 8-[2-(4-bromo-phenyl)-ethyl]-3-ethyl-1-iodo-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine. LC-MS: tR=0.74 min.; [M+H]+=460.01 g/mol.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 1.03 g (4.82 mmol) 3-(4-bromo-phenyl)-propionaldehyde and 0.41 mL (4.82 mmol) pyrrolidine in 50 mL MeOH is adjusted to pH 4-5 with glacial acetic acid. Then 400 mg (6.05 mmol) NaBH3CN are added batchwise and the reaction is stirred for 3 days at RT. The reaction solution is diluted with 30 mL water and the aqueous phase is extracted with 50 mL EtOAc. The organic phase is dried over Na2SO4 and the solvent is eliminated i.vac. Further purification is carried out by column chromatography on silica gel (EtOAc/MeOH/NH3 9:1:0.1). the aqueous phase is extracted with 50 mL EtOAc The organic phase is dried over Na2SO4 Further purification

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 210 mg (0.86 mmol) Pd(OAc)2, 5.23 g (17.32 mmol) tetra-n-butylammonium chloride and 3.6 g NaHCO3 are added to a solution of 5.0 g (17.32 mmol) 4-bromo-iodo-benzene and 3.0 mL (43.67 mmol) allylalcohol in 30 mL DMF. The reaction solution is stirred for 2 h at 60° C. and diluted with 50 mL water. The aqueous phase is extracted with 50 mL EtOAc and the combined organic extracts are washed with 50 mL saturated NaCl solution. The organic phase is dried over Na2SO4 and the solvent is eliminated i.vac. Further purification is carried out by column chromatography on silica gel (cyc/EtOAc 3:1). The aqueous phase is extracted with 50 mL EtOAc the combined organic extracts are washed with 50 mL saturated NaCl solution The organic phase is dried over Na2SO4 Further purification