title: A new, easily recyclable arylating agent based on a diphosphino-digold(I) complex.
abstract: The synthesis of two organogold(I) complexes, [(Au(NCN))2(dppbp)] (6) and [(Au(Phebox))2(dppbp)] (9), and their application in subsequent transmetalating reactions are described. A trinuclear organogold(I) complex, [(AuCl)3(tdpppb)] (4) is also reported, which exhibits a surprisingly high solubility in dichloromethane. It was found that 6 and 9 can cleanly transfer the anionic NCN-([C(6)H(3)(CH(2)NMe(2))2-2,6]-) or Phebox-([2,6-bis(oxazolinyl)phenyl]-) moiety to Ti(IV) and Pd(II) centers, respectively. The coproduct [(AuCl)2(dppbp)] (3, dppbp is [4-Ph(2)PC(6)H(4)]2 (1)) formed during this transmetalation reaction, precipitates almost quantitatively from the reaction mixture (toluene) and can thus be separated by simple filtration. In comparison, [AuCl(PPh3)], formed as the coproduct in the transmetalation reaction of [Au(NCN)(PPh3)] with metal salts, has a higher solubility in apolar solvents and thus is more difficult to separate from the resultant organometallic complex. Digold complex 6 has been characterized by NMR spectroscopy and crystallographic analyses. These analyses show that the two gold units are essentially independent. The formation of a dimetallic transmetalating agent based on gold(I) had no effect on its transmetalating properties.
authors.affiliation: Organic Chemistry and Catalysis, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
authors.forename: Marianne
authors.initials: M
authors.lastname: Stol
authors.forename: Dennis J M
authors.initials: DJ
authors.lastname: Snelders
authors.forename: Huub
authors.initials: H
authors.lastname: Kooijman
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Spek
authors.forename: Gerard P M
authors.initials: GP
authors.lastname: van Klink
authors.forename: Gerard
authors.initials: G
authors.lastname: van Koten