Air-Stable Tri-tert-butylphosphine Equivalent

Tri-tert-butylphosphine is expected to exhibit unusual and unique reactivity different from other phosphine ligands because of its electron-richness and bulkiness. However, tri-tert-butylphosphine is rather air-sensitive, which makes it difficult to handle. Tri-tert-butylphosphonium tetrafluoroborate (1) is stable enough to be stored in air for a long period. By using tri-tert-butylphosphine in situ generated from 1, various kinds of coupling reactions can be demonstrated.