362017-05-8Relevant academic research and scientific papers
Two-, three-, and four-coordination at gold(I) supported by the bidentate selenium ligand [PH2P(Se)NP(Se)PH2]-
Wilton-Ely,Schier,Schmidbaur
, p. 4656 - 4661 (2008/10/08)
Treatment of the gold(I) halide complexes LAuCl (L = PMe3, PPh3, CNC6H3Me2-2,6) with K[Ph2P(Se)NP(Se)Ph2] provides the gold-selenium coordination compounds [{N(Ph2PSe)2-Se,Se′}AuL]. However, on standing for a number of days, the complex [{N(Ph2PSe)2-Se,Se′}AuPMe3] gains a phosphine to provide the bis(phosphine) species [{N(Ph2PSe)2-Se,Se′}Au(PMe3) 2]. Treatment of the K[Ph2P(Se)NP(Se)Ph2] ligand with [(Ph3PAu)3O]BF4 allows the isolation of [{N(Ph2PSe)2-Se,Se′}(AuPPh3)2]BF 4. Reaction of the complex [(dppm)(AuCl)2] with AgSO3CF3 followed by addition of the ligand K[Ph2P(Se)NP(Se)Ph2] results in the formation of [{N(Ph2PSe)2Se,Se′}Au2(dppm)]OSO 2CF3 and treatment of [(tht)AuCl] (tht= tetrahydrothiophene) with an equimolar quantity of K[Ph2P(Se)NP(Se)Ph2] affords the complex [{N(Ph2PSe)2-Se,Se′}2Au2]. The compounds [{N(Ph2PSe)2-Se,Se′} Au2(dppm)]OSO2CF3, [{N(Ph2PSe)2-Se,Se′} AuPPh3] and [{N(Ph2PSe)2-Se,Se′ Au(PMe3)2 have been investigated crystallographically. The results reveal that the metal centers are two-, three-, and four-coordinate, respectively. The cationic, eight-membered ring complex bearing the dppm ligand displays transannular aurophilic bonding and is further associated into dimers via intermolecular gold-selenium contacts. The six-membered rings in the other two structures have C2-symmetrical twist conformations, however, the Au(I) coordination sphere in [N(PPh2Se)2]AuPPh3 is not fully symmetrical. The Au-Se bond lengths increase dramatically as the coordination number of the metal atom becomes larger.
