A mild and improved synthesis of disecondary phosphines PhPH(CH2)nPHPh (where n = 1-6), have been prepared. In the presence of phenylphosphine, cesium hydroxide, activated 4 Å molecular sieves and DMF, numerous dialkyl halides reacted efficiently to produce various disecondary phosphines exclusively at room temperature.
Keywords: primary phosphine, cesium hydroxide monohydrate, dialkyl halide, disecondary phosphine, phosphine macrocycle