Tetrabutylammonium Fluoride → tert-Butyl 5,6-dihydroimidazo(1,2-a)pyrazine-7(8H)-carboxylate

Participants

Reaction Steps

Tetrabutylammonium fluoride (1M in tetrahydrofuran, 7.1 mL, 7.1 mmol) was added to a solution of 1,1-dimethylethyl N-(2-chloroethyl)-N-(1-{[2-(trimethylsilyl)ethoxy]methyl}-1H-imidazole-2-ylmethyl)carbamate (Description 162, 2.52 g, 6.5 mmol) in tetrahydrofuran (50 mL) and the mixture was heated under reflux for 1.5 hours. Further tetrabutylammonium fluoride (1M in tetrahydrofuran, 7.1 mL, 7.1 mmol) was added and the mixture was heated under reflux for 20 hours. The mixture was cooled and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with CH2Cl2/MeOH (97:3), to give the title compound (505 mg, 35%). m/z (ES+) 224 (M+1).

Provenance & Evidence