Facile synthesis of a tricyclohexylphosphine-stabilized h3-allyl-carboxylato Ni(II) complex and its relevance in electrochemical butadiene carbon dioxide coupling.
Applied Organometallic Chemistry, (2005)Abstract
With the reaction of bis(1,5-cyclooctadiene)nickel(0) and trans-penta-2,4-dienoic acid in the presence of tricyclohexylphosphine, a new more general method was developed to synthesize cyclic p3-allyl-carboxylato Ni(II) complexes, which are known to be intermediates in the C-C coupling of butadiene and CO2. The cyclic p3-allyl-carboxylato Ni(II) complex obtained was tested as a mediator in the electrochem. coupling reaction of butadiene and CO2. The authors also demonstrate the dependency on the coordination sphere by using Pt instead of Ni as the metal center; Pt(cod)2, trans-penta-2,4-dienoic acid and PMe3 gave an oxaplatinacyclopentanone whereas Pt(cod)2, hexa-2,4-dienoic acid and PCy3 gave trans-(Cy3P)2PtH(O2CCH:CHCH:CHMe). The crystal and mol. structures of the (Cy3P)Ni(CH2CH:CHCH2CO2) chelate were detd. by x-ray crystallog. on SciFinder (R)