Palladium(II) complexes of anthraquinone-based As–O–As type and Se–O–Se type bipodands. Synthesis, X-ray crystallography and catalytic properties

• Arsenic (L1) containing anthraquinone-based open bipodand has been synthesized.
• [Pd(PhCN)2]Cl2 chelates with L1 and its selenium analogue (L2).
• Palladium possesses square planar geometry in both complexes.
• Palladium complex of selenium analogue act as a catalyst for the Heck reaction.
• Electrochemistry reveals the redox behavior of the anthraquinone and heteroatoms.

The reaction of the Ph2As− anion with 1,8-bis(2-bromoethoxy)anthracene-9,10-dione in 2:1 ratio generates 1,8-bis(2-diphenylarsinoethoxy)anthracene-9,10-dione (L1). L1 and 1,8-bis(2-phenylselenoethoxy)anthraquinone (L2) reacted with bis(benzonitrile)palladium(II) chloride in 1:1 ratio yielding Pd(L1)Cl2 (1) and Pd(L2)Cl2 (2). X-ray structures of 1 and 2 revealed that L1 and L2 chelate with Pd(II) and form a convex square planar geometry. The catalytic properties of both Pd(II) complexes in the Heck reaction was investigated, and the results show that compound 2 acts as a better catalyst than 1. The redox behavior of L1, 1 and 2 versus Ag/AgCl are also explored.

New organoarsine containing anthraquinone-based open bipodand ligand and its Pd(II) complex have been synthesized and characterized. X-ray structures of complex shows that the ligand chelates with Pd(II) and formed a 14 membered palladacycle. One of the palladium complex reported here serves as a catalyst for the Heck reaction. Electrochemical behaviors of new compounds versus Ag/AgCl are also discussed.Figure optionsDownload as PowerPoint slide