Study on the intramolecular transannular chalcogen–tin interactions in dithiastannecine compounds
作者:Diego Martínez-Otero、José G. Alvarado-Rodríguez、Julián Cruz-Borbolla、Noemí Andrade-López、Thangarasu Pandiyan、Rafael Moreno-Esparza、Marcos Flores-Alamo、Jesús Cantillo-Castillo
DOI:10.1016/j.poly.2011.11.053
日期:2012.2
Dithiastannecine compounds of the type [D(C6H4CH2S)(2)}(SnRR2)-R-1] with different donor atoms D were prepared, where D = O and R-1 = R-2 = Ph (4a); R-1 = Ph, R-2 = Cl (5a); R-1 = n-Bu, R-2 = Cl (6a); D = S and R-1 = R-2 = Ph (4b): R-1 = Ph, R-2 = Cl (5b); R-1 = n-Bu, R-2 = Cl (6b). The molecular structures of the monochloro compounds 5a, 51). 6a, and 6b were established by single-crystal X-ray diffraction and exhibit trigonal bipyramidal geometry at the tin atom with different degrees of distortion being due a D center dot center dot center dot Sn interaction. The Spiro compounds [D(C6H4CH2S)(2)}(2)Sn] with D = O (7a) and D = S (7b) were also synthesized and structurally characterized; the molecular structure of 7a showed the tin atom with a bicapped tetrahedral geometry. The behavior of all tin compounds in solution was investigated by NMR spectroscopy revealing that the D center dot center dot center dot Sn interaction in solution was practically absent on the basis of the NMR chemical shifts values. DFT calculations with ADF package using VWN/QZ4P were carried out for the 6a and 6b compounds and showed that, in the topological analysis, bond critical points are present along the D center dot center dot center dot Sn direction. (C) 2011 Elsevier Ltd. All rights reserved.