(Cyanomethyl)triphenylphosphonium chloride → 3-[4-(2,6-Dioxo-1,3-dipropyl-2,3,6,7-tetrahydro-1H-purin-8-yl)-bicyclo[2.2.2]oct-1-yl]-acrylonitrile

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of 4-(2,6-dioxo-1,3-dipropyl-2,3,6,7-tetrahydro-1H-purin-8-yl)-bicyclo[2.2.2]octane-1-carbaldehyde (535 mg, 1.44 mmol) and (cyanomethyl)triphenylphosphonium chloride (1.2 eq, 1.73 mmol, 582 mg) in THF (30 ml) at 0° C. was added KHMDS (0.5 M in toluene, 2.2 eq, 3.16 mmol, 6.3 ml). The resulting mixture was stirred for 1.5 h at this temperature then heated at 55° C. for 5 h. The cool reaction mixture was partitioned between EtOAc (10 ml) and a saturated aqueous NH4Cl solution (20 ml) and the aqueous phase was extracted with EtOAc (20 ml). The combined organic phases were washed with a saturated aqueous NaCl solution (2×20 ml), dried (MgSO4), filtered and evaporated to give a solid residue that was purified by radial chromatography (2 mm plate) using 5% MeOH in CH2Cl2 as eluent to afford 425 mg (75%) of a brittle foam (mixture of cis/trans isomers). MS: 396 (MH+).

Provenance & Evidence