Synthesis and single crystal structural investigations on quaternary salts of tellurated alkylamine derivatives

Abstract

Tellurated alkylamine derivatives 4 - CH 3 OC 6 H 4 Te ( CH 2 ) 2 NH 3 + Cl - ( 1 ) , 4 - CH 3 OC 6 H 4 Te ( Cl 2 ) ( CH 2 ) 3 NH 3 + Cl - ( 2 ) , Cl 2 Te ( ( CH 2 ) 2 NH 3 + Cl - ) 2 ( 3 ) and Cl 2 Te ( ( CH 2 ) 3 NH 3 + Cl - ) 2 ( 4 ) have been synthesized by reacting appropriate organic halides with the nucleophile 4-CH 3OC 6H 4Te − or Te 2− generated in situ by borohydride reduction of (4-CH 3OC 6H 4Te) 2 or Te powder followed by reaction with HCl of appropriate concentration. The zwitterionic species [ − Cl 4 Te ( CH 2 ) 3 NH 3 + ] was generated when single crystals of 2 were grown in methanol at 0 °C. Complexes 1– 4 exhibit characteristic 1H NMR spectra. The single crystal structures of 1– 4 and 2a have been determined. In the crystals of 1, C–H⋯π distances have been found to be 3.31(7)–3.59(5) Å. In both 2 and 2a, weak Te⋯Cl interactions (3.54(2) –3.62(2) Å) are observed. The C–H⋯π distance in the crystal of 2 is 3.19(0) Å. In 2a and 3, water hydrogen bonds connect the water molecules with the end NH 3 + groups from different molecules. In the case of 3, Te⋯Cl weak interactions involving the Cl − ions connect together two such chains. The geometry of Te in 1 is V shaped. In 2 and 3 it is pseudo trigonal bipyramidal, and in 2a, it is square pyramidal. However, in the latter case it becomes distorted octahedral due to weak Te⋯Cl secondary interactions. The geometry about Te in 4 is distorted octahedral due to weak Te⋯Cl interactions involving Cl − ions. However, there are no intermolecular Te⋯Cl interactions.