Study on Some Hydroxyaryltellurium(IV) Trichlorides Catalyzed Knoevenagel Reactions

Abstract

Hydroxyaryltellurium trichlorides, R'TeCl₃ (p-hydroxyphenyl and 3-methyl-4-hydroxyphenyl) have been prepared by condensation of tellurium tetrachloride with phenol or o-cresol respectively. These hydroxyaryltellurium trichlorides have been investigated as catalysts in Knoevenagel reactions between non-enolizable aldehydes and active methylene compounds to yield the corresponding olefinic products. This paper reports the reaction of ethylcyanoacetate, malononitrile and cyanoacetamide with aromatic aldehydes, ArCHO (Ar is C₆H₅, 4-ClC₆H₄, 4-CH₃OC₆H₄ and C₆H₅-CH=CH). The products are obtained in excellent yield and high purity and have been identified by comparison of their properties with those of authentic samples.