Synthesis, characterization and crystal structures of triorganotin(IV) complexes of 4‐[(<i>E</i>)‐2‐(3‐formyl‐4‐ hydroxyphenyl)‐1‐diazenyl]‐ and 4‐{(<i>E</i>)‐4‐hydroxy‐3‐[(<i>E</i>)‐4‐(aryl)iminomethyl]phenyldiazenyl}‐benzoic acids and toxicity studies of their tri‐<i>n</i>‐butyltin(IV) derivatives on the <i>Aedes aegypti</i> and <i>Anopheles stephensi</i> mosquito larvae

Abstract

Abstract Triorganotin(IV) complexes of 4‐[( E )‐2‐(3‐formyl‐4‐hydroxyphenyl)‐1‐diazenyl]‐ and 4‐{( E )‐4‐hydroxy‐3‐[( E )‐4‐(aryl)iminomethyl]phenyldiazenyl}‐benzoic acids (aryls = 4‐CH 3 , 4‐Br, 4‐Cl, 4‐OCH 3 ) have been synthesized. The structures have been characterized by 1 H, 13 C, 119 Sn NMR, IR and 119m Sn Mössbauer spectroscopies. The crystal structures of Ph 3 Sn[O 2 CC 6 H 4 {NN(C 6 H 3 ‐4‐OH[C(H)NC 6 H 4 CH 3 ‐4])}‐ p ] and n Bu 3 Sn[O 2 CC 6 H 4 {NN(C 6 H 3 ‐4‐OH[C(H)NC 6 H 4 Br‐4])}‐ p ] are also reported. The 119 Sn Mössbauer and 119 Sn NMR data indicate that the tri‐ n ‐butyltin(IV) and triphenyltin(IV) complexes have a tetrahedral geometry in the solid state as well as in solution. Toxicity studies of the tri‐ n ‐butyltin(IV) complexes on the second larval instar of the Aedes aegypti and Anopheles stephensi mosquito larvae indicated that the complexes are effective larvicides. The LC 50 values range from 1.21 to 3.38 µ M for the Ae. aegypti and from 0.83 to 2.31 µ M for the An. stephensi . Copyright © 2006 John Wiley &amp; Sons, Ltd.