a b s t r a c tA series of square-planar palladium(II) benzisothiazolinate (bit) of the general type [Pd(bit) 2 L 2 ] have been prepared and characterized by analytical and spectroscopic methods. Two synthetic routes have been employed, namely reactions of [Pd(bit) 2 ]ÁH 2 O with two equivalents of ligands (L = amine, amide, phosphine) or nucleophile displacement of chloride by benzisothiazolinate starting from trans-[PdCl 2 L 2 ]. Both routes afford the new complexes in good yields as easily isolated, air and moisture stable, colored solids. The precursor, [Pd(bit) 2 ]ÁH 2 O, is itself prepared in high yields upon reaction of Na[bit] with Na 2 [PdCl 4 ] in methanol and the analogous platinum complex, [Pt(bit) 2 ]ÁH 2 O, is similarly prepared from K 2 [PtCl 4 ]. It is not clear if these species are mono-or dimeric, and formulation as [M 2 (l-bit) 4 (H 2 O) 2 ] with the four benzisothiazolinate spanning the metal-metal vector and possibly binding through coordination of nitrogen and oxygen is suggested. Diphosphine adducts, cis-[Pd(bit) 2 {j 2 -Ph 2 P(CH 2 ) n PPh 2 }] (n = 1-4) can be prepared both upon addition of the diphosphine to [Pd(bit) 2 ]ÁH 2 O and from reactions of cis-[PdCl 2 {j 2 -Ph 2 P(CH 2 ) n PPh 2 }] with two equivalents of Na [bit]. A crystal structure of cis-[Pd(bit) 2 (j 2 -dppe)] reveals that the benzisothiazolinate ligands are bonded in a monodentate fashion through nitrogen and this binding mode is proposed for all [Pd(bit) 2 L 2 ] and [Pd(bit) 2 L] complexes. With dppb (n = 4) a second product is seen by NMR spectroscopy being proposed to be the part-substituted complex cis-[PdCl(bit)(j 2 -dppb)], while with dppm (n = 1) two further products are seen spectroscopically, proposed as trans-[Pd(bit) 2 (j 1 -dppm) 2 ] and (more tenuously) [Pd 2 (bit) 4 (dppm) 2 ]. The former is also prepared in good yields from reaction of [Pd(j 2 -dppm) 2 ]Cl 2 with Na [bit]. These studies show that palladium benzisothiazolinate are easily accessed and show good air and moisture stability.