The reduction of the nickel(II) chloride complexes [NiCl 2(dippm)] ( 1a, dippm = 1,1-bis(diisopropylphosphino)methane), [NiCl 2(dippe)] ( 1b, dippe = 1,2-bis(diisopropylphosphino)ethane), and [NiCl 2(dippp)] ( 1c, dippp = 1,3-bis(diisopropylphosphino)propane) with one equivalent of potassium naphthalenide in tetrahydrofuran (THF) gives the corresponding nickel(I) chlorides [NiCl(dippm)] ( 2a), [NiCl(dippe)] ( 2b) and [NiCl(dippp)] ( 2c). The bidentate phosphine-Ni 0 intermediates formed by reduction of the Ni II chlorides 1a and 1b with an excess of magnesium, also give the mono-chlorides 2a and 2b on reaction with equal molar amounts of 1a and 1b, respectively. The reduction of 1b and 1c with magnesium in the presence of naphthalene produces the nickel(0) complexes [Ni(C 10H 8)(dippe)] ( 4b) and [Ni(C 10H 8)(dippp)] ( 4c, C 10H 8 = naphthalene). A crystal structure study of 4b showed that the naphthalene molecule is η 2-bonded to the P 2Ni unit.