Water → 4-[2-Methoxyethenyl]-1-phenylbicyclo[2.2.2]octane

Participants

Reaction Steps

To an ice water cooled stirred suspension of (methoxymethyl)triphenylphosphonium chloride (17 g, 49.57 mmol) in anhydrous THF (100 mL) under nitrogen was added lithium bis(trimethylsilyl)amide (1M solution in THF; 50 mL, 50 mmol), and the reaction mixture was allowed to stir at 0° C. for 30 mins. 1-Phenylbicyclo[2.2.2]octane-4-carbaldehyde (Intermediate 6; 10.52 g, 49.08 mmol) in THF (20 mL) was added dropwise and the reaction mixture was allowed to stir at 0° C. for one hour and then at ambient temperature overnight. Water (100 mL) was added and the reaction mixture was partitioned between EtOAc (200 mL) and brine (100 mL), the organic phase was washed with an additional 100 mL of brine then separated, dried (MgSO4) and concentrated to leave a pale yellow gum. The residue was purified on a 330 g Presearch silica cartridge, loading in isohexane/DCM and eluting 0-20% EtOAc-isohexane to provide the title compound as a pale yellow oil (12.6 g, 50.19 mmol, 100%) as a 1:2 mixture of E:Z isomers; E isomer 1H NMR (CDCl3) δ 1.60-1.65 (2H, m), 1.82-1.88 (10H, m), 3.49 (3H, s), 4.74 (1H, d), 6.18 (1H, d), 7.12-7.18 (1H, m), 7.25-7.34 (4H, m); Z isomer: 1H NMR (CDCl3) δ 1.60-1.65 (2H, m), 1.82-1.88 (10H, m), 3.54 (3H, s), 4.09 (1H, d), 5.71 (1H, d), 7.12-7.18 (1H, m), 7.25-7.34 (4H, m); MS (same for both individual isomers): GC-MS EI+ m/e 242 (M+).

Provenance & Evidence