Chloroacetaldehyde → Imidazo(1,2-a)pyrazine

A solution of aminopyrazine (1 g, 10.5 mmol) and chloroacetaldehyde (50% wt in H2O; 1.98 g, 12.6 mmol) in 1.6 mL of EtOH was heated at 90° C. in a sealed tube for 5 h. Upon cooling to ambient temperature, the reaction mixture was concentrated and diluted with dichloromethane (DCM). The organic layer washed with saturated aqueous NaHCO3 then dried over MgSO4 and concentrated. The crude product was purified by silica gel flash chromatography (eluted with 10% MeOH/DCM) to provide 0.8 g of product.

1. concentrationthe reaction mixture was concentrated
2. additiondiluted with dichloromethane (DCM)
3. washThe organic layer washed with saturated aqueous NaHCO3
4. dry with materialthen dried over MgSO4
5. concentrationconcentrated
6. customThe crude product was purified by silica gel flash chromatography (eluted with 10% MeOH/DCM)

ORD record

ord-a519d605d2b04776bb33472559c68021

Source dataset

uspto-grants-2015_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09029533B2