Synthesis, structure and properties of [1,2,4]triazolo[4,3-a]pyridin-3-ylidene rhodium and palladium complexes.
The reaction of [1,2,4]triazolo[4,3-a]pyridinium tetrafluoroborates with [RhCl(COD)](2) and [PdCl(allyl)](2) takes place under mild basic conditions (Et(3)N, THF, room temperature) to afford the corresponding [RhCl(COD)(Tripy)] and [PdCl(allyl)(Tripy)] complexes, respectively (Tripy = [1,2,4]triazolo[4,3-a]pyridin-3-ylidene), and their structures were analysed by X-ray diffractometry and spectroscopic techniques. The sigma-donor ability of the new ligands was estimated by comparative analysis of infrared nu(CO) stretching frequencies of [RhCl(CO)(2)(Tripy)] complexes, and proved to be strongly dependent on the substitution pattern. Additionally, a first insight into the catalytic properties of the latter in the Suzuki-Miyaura cross coupling demonstrates a good catalytic activity that enables the coupling of aryl chlorides at room temperature.
Iglesias-Sigüenza
Javier
J
Departamento de Química Orgánica, Univ. de Sevilla, Apdo. de Correos 1203, 41071, Seville, Spain.
Ros
Abel
A
Díez
Elena
E
Alcarazo
Manuel
M
Alvarez
Eleuterio
E
Fernández
Rosario
R
Lassaletta
José M
JM
D002384:Catalysis; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism
D009942:Organometallic Compounds; D010165:Palladium; D012238:Rhodium