Co(II)@KCC-1 as a Novel Metal Salen Complex for the Synthesis of Spirooxindole Derivatives

Homogeneous metal salen complexes were developed for the synthesis of a variety of organiccompounds. Despite good catalytic activity, some drawbacks such as contamination of productsand tedious work up as well as lack of economic efficiency restricted the use of thesecatalysts. Covalent attachment of metal salen complexes on a solid support such as polymer,zeolite and silica have recently been reported as innovation in the catalytic properties of suchcompounds [1]. Fibrous Nano-Silica (KCC-1) which has excellent physical properties, includinghigh surface area, fiber morphology, good thermal properties and high mechanical stabilityare a good candidate for supporting metal salen complexes [2]. On the other hand, the oxindolecompounds containing a spiro-cyclic stereo center are an important class of oxygencontainingheterocycles and medicinal scaffolds which are widely distributed in natural compoundssuch as alkaloids as well as synthetic drugs. Spirooxindoles have a wide range of biologicalactivities including antiviral, anticancer, anti-inflammatory and antimicrobial activities[3]. Therefore, the synthesis of spirooxindole derivatives is still the subject of extensive research.In this study, we synthesized the Co(II) salen complex and supported on KCC-1 correspondingCo(II)@KCC-1 and the synthesis of spirooxindole derivatives was investigated inthe presence of this catalyst in green media (Fig. 1).