An efficient synthesis of Ph2P-C≡ CC≡ C-Li, 1, was found, starting from commercially available (Z)-1-methoxybut-1-ene-3-yne and its diphenylphosphino derivative 2. The lithio compound 1 was condensed with electrophiles to give Ph2P-C≡ CC≡ C—Σ (Σ= SiR3, SnR3, B (NiPr) 2) 3. Compound 2 was easily transformed into the phosphonium salt 6 and the phosphine oxide 7 using MeI and H2O2 respectively. Derivatives 3 (Σ= SiMe3, SnMe3 ...
