A mechanistic insight into metal-cluster π-envelopment: a dual binding mode involving bent and planar ligand-conformers. Issue 38 (20th April 2016)

• Record Type: Journal Article
• Authors: Masai, Kohei; Shirato, Katsunori; Yamamoto, Koji; Kurashige, Yuki; Murahashi, Tetsuro
• Is Part Of: Chemical communications. Volume 52:Issue 38(2016)
• Page Start: 6427
• Page End: 6430
• Publication Date: 2016-04-20
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1039/c6cc01536k
• Languages: English
• ISSNs: 1359-7345

Abstract

Abstract : We report a stepwise mechanism of the π-envelopment of a Pd4 chain cluster. Bent- and planar binding modes of π-conjugated unsaturated hydrocarbon ligands are involved in the π-envelopment process. Abstract : Metal clusters are effectively stabilized by bridging π-coordination of planar π-conjugated unsaturated hydrocarbons. However, the mechanism of π-envelopment of a metal cluster has been elusive. By employing 1, 2-bis(4-aryl-1, 3-butadienyl)benzene as the π-conjugated ligand, we found that the π-envelopment of a Pd4 cluster proceeded in a stepwise manner, where the sp 2 -carbon ligands initially envelop the Pd4 cluster through a bent binding mode, and then isomerized to a thermodynamically more stable planar mode under mild heating or visible light irradiation. The involvement of a bent binding mode indicates the kinetically preferred coordination at the axial coordination site trans to a metal–metal bond.