Triphenylphosphine → cis 2-[3-(Tert-butyl-dimethyl-silanyloxy)-cyclopentyl]-5,6-dichloro-isoindole-1,3-dione

Participants

Reaction Steps

To a round bottomed flask was added trans 3-(tert-butyl-dimethyl-silanyloxy)-cyclopentanol (1.0 g, 4.62 mmol, prepared from WO2008065021), triphenylphosphine (1.52 g, 5.76 mmol) and 2-methyltetrahydrofuran (120 mL). Diisopropyl azodicarboxylate (1.23 mL, 6.25 mmol) was added over two minutes via syringe followed by 4,5-dichlorophthalimide (1.35 g, 6.25 mmol). The reaction was stirred overnight and evaporated. The reaction was repeated and the combined material was purified by column chromatography (160 g SiO2, EtOAc in hexane) to give cis 2-[3-(tert-butyl-dimethyl-silanyloxy)-cyclopentyl]-5,6-dichloro-isoindole-1,3-dione, a yellowish solid (2.0 gm, 52% yield)

Provenance & Evidence