Synthesis of fluorophenyl carbonyl cobalt(I) complexes and decarbonylation of 2,4,5-trifluorobenzaldehyde catalyzed by CoMe(PMe3)4

Abstract Three fluorophenyl carbonyl cobalt(I) complexes Ph F (PMe 3 ) 3 Co(CO) ( 1–3 ) were synthesized by the reaction of fluoro-benzaldehydes with CoMe(PMe 3 ) 4 via C–H bond activation and decarbonylation reaction. The dicarbonyl cobalt(I) complex (2,4-F 2 C 6 H 3 )Co(CO) 2 (PMe 3 ) 2 ( 4 ) was obtained by reacting of complex 1 with CO. Complex 1 reacted with pentafluorobromobenzene afforded cobalt(II) bromide (2,4-F 2 C 6 H 3 )Co(Br)(PMe 3 ) 3 ( 5 ) with the formation of perfluorinated diphenyl. The reaction of complex 3 and phenylacetylene delivered the hydrido diethinyl cobalt(III) complex (PhC C) 2 Co(H)(PMe 3 ) 3 ( 6 ) with 1,2,4-trifluorobenzene as a byproduct. The molecular structures of 1 , 4 and 5 were determined by X-ray diffraction. Furthermore, we found that CoMe(PMe 3 ) 4 could be used as a catalyst for the catalytic decarbonylation of 2,4,5-trifluorobenzaldehyde with triethylsilane as a hydrogen source.