New polynuclear organotin(IV)-nitrogen compounds. Synthesis and crystal structures of [(PhSn)(4)(NPh)(5)Cl-2] and [(MeSn)(4)(NHPh)(4)(NPh)(4)]

The reaction of the organotin halides PhSnCl3 and MeSnCl3 with LiNHPh leads to the formation of two new nitrogen bridged organotin compounds, [(PhSn)( 4)(NPh)(5)Cl-2] (1) and [(MeSn)(4)(NHPh)(4)(NPh)(4)] (2). The crystal struc tures of 1 and 2 have been determined by low temperature X-ray diffraction. 1 contains a bicyclic Sn4N5 framework, which consists of two six-membered Sn3N3-rings. All tin atoms are coordinated nearly tetrahedrally. Two tin at oms are bonded to a phenyl group and three nitrogen atoms, the other two ti n atoms are coordinated by a phenyl group, two nitrogen atoms and a termina l chlorine atom. In 2 the tin atoms define the corners of a distorted squar e. Each edge of the square is bridged by a mu(2)-NHPh and a mu(2)-NPh group . The bridging NHPh and NPh groups are arranged at opposite sides of the Sn -4 plane. The tin atoms are coordinated square pyramidally by 4 nitrogen at oms and a methyl group.