New Organophosphorus Ligands: 1,1,2‐Tris(diphenylphosphanyl)cyclopropane and Its Derivatives

Cyclopropanation of 1,1,2-tris(diphenylphosphanyl)ethene with dimethylsulfonium methylide affords the title compound 1. The trifunctional phosphane is transformed into the trioxide 2 and trisulfide 3 by oxidation with hydrogen peroxide or elemental sulfur, respectively. With the tetrahydrofuran — borane complex the tris(phosphane—borane) 4 is obtained. The crystal structure of compound 1 has been determined by single-crystal X-ray diffraction.