The first solid-supported Cp′Co(I)-catalyst for the synthesis of pyridines

• Novel air-stable Cp′Co(I)-complex with alkylsiloxane tether as solid support linker.
• Optimized synthesis of substituted cyclopentadienes and air-stable Cp′Co(I)-complex.
• Investigation of Cp′Co(I)-complex towards support on sol–gel matrices as well as SiO2.
• Solid phase-supported Cp′Co(I)-catalysts for cyclotrimerizations affording pyridines.
• Best results for SiO2-supported catalyst in reaction between diyne and nitrile.

We report on the successful modification of the air-stable CpCo(I)-complex [CpCo(trans-MeO2CCHCHCO2Me){P(OEt)3}] (2) in order to enhance its recyclability by covalently linking this highly active catalyst for cycloaddition reactions on several solid supports. While the sol–gel-entrapped catalyst yielded no cycloaddition product, the silica-bound analogue led to the formation of the pyridine derivative, representing the first solid-supported Cp′Co(I)-complex to catalyze the cyclotrimerization of a diyne and a nitrile.

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