Two new carbon-free indium(III) asymmetric chelates - Synthesis and X-ray crystal structures of [In{Ph2P(O)NP(S)Ph-2-O,S}(3)]center dot 3/4 C6H6 and [InCl{Ph2P(S)NP(Se)Ph-2-S,Se}(2)]

The ligands [Ph-2(S)PNHP(X)Ph-2](-) (X = O, Se) react with InCl3 in a 3:1 r atio to give a tris-chelate [In{Ph2P(O)NP(S)Ph-2-O,S}(3)]. 0.75 C6H6 (2) an d the unexpected pentacoordinate derivative [InCl{Ph2P(Se)NP(S)Ph-2-Se,S}(2 )] (3). These compounds have been characterized by means of IR, H-1- and P- 31-NMR spectroscopy, positive-ion FAB mass spectrometry and elemental analy sis. The molecular structures have been determined by single-crystal X-ray diffraction analysis. The coordination geometry in 2 resembles that observe d in the three analogous tris-chelates incorporating the corresponding symm etrical oxygen, sulfur and selenium ligands. Compound 3 exhibits a very dis torted trigonal-bipyramidal geometry at indium, where both the selenium and chlorine atoms are in equatorial positions, while the sulfur atoms are in axial positions.