COMPARISON OF STRUCTURES OF SIX ALKARYLSTANNYL OR ALKYLSTANNYL DITHIOPHOSPHATES. Yao Xinkan, Wang Honggen, Xie Qinglan, Luo Ning, Yang Zhiqiang, Central Laboratory, Nankai University, Tianjin, 300071, China

In various alkarylstannyl and alkylstannyl dithiophosphates the steric hindrance effect clearly play a determinant role in forming four-coordinate or six-coordinate tin species. Triphenylstannyl and tricyclohexylstannyl derivatives are sure to be four-coordinate tin species, and diphenylstannyl or other less-steric-factor alkylstannyl derivatives are sure to be six-coordinate tin species.

These derivatives have been variously studied owing to their functions as fungicides and miticides. Only a few structures of these derivatives were reported. ^[1-4] We now present x-ray structure analyses of tricyclohexylstannyl (O,O'-di-p-chlorophenyl) dithiophosphate (compound I) and dibutylstannyl (O,O'-p-tolyl) dithiophosphate (compound II). The structural characteristics of these two compounds, along with the other four compounds are summarized in Table 1.

Table 1 Selected Bonds and Local Geometry at Tin

compd Sn-S(1)^a Sn-S(2)^b P-S(1)^c P-S(2)^d Geometry at Tin Ref

                                                            
I    2.502(2)  3.597*   2.030(3  1.914(3)  tetrahedr        
                        )                  on               
II   2.495(3)  3.244(4  2.029(3  1.927(4)  octahedro        
               )        )                  n                
     2.493(2)  3.228(3  2.025(4  1.932(4)                   
               )        )                                   
III  2.458(9)  5.326*   2.054(1  1.931(1)  tetrahedr  [1]   
                        )                  on               
IV   2.678(1)  2.689(1  2.006(2  1.998(2)  octahedro  [2]   
               )        )                  n                
V    2.48(2)   3.334(2  2.047(2  1.969(2)  octahedro  [3]   
               )        )                  n                
VI   2.48(1)   3.20(1)  2.04(2)  1.92(3)   octahedro  [4]   
                                           n                
     2.49(1)   3.23(1)  2.03(1)  1.94(1)                    

V = [(MeO)₂P(S)S]₂Sn(CH₃)₂ VI = [(EtO)₂P(S)S]₂SnPh₂

a: Sn-S b: Sn ~S c: P-S d: P=S *: no-bonding

[1] Molloy, K.C., et al, Inorg. Chem., 1979, 18, 3507

[2] Molloy, K.C., et al, Inorg. Chem., 1980, 19, 2041

[3] Molloy, K.C., et al, Inorg. Chem., 1981, 20, 2172

[4] Lieblich, B.W., et al, Acta Crystallog., 1978, B34, 944