Preparation and Characterization of the Argentates: Ag P(CF3)2 2(-), Ag(mu-P(CF3)2)M(CO)5 2(-) (M = Cr, W) and Ag mu-P(C6F5)2)W(CO)5 2(-): X-Ray Crystal Structure of K(18-Crown-6)Ag mu- P(CF3)2)Cr(CO)5 2

摘要

The novel bis bis(trifluorom ethyl)phosphanido argentate, Ag(P(CF3) 2 2(-), is obtained via the reaction of HP(CF3)2 with Ag(CN)2(-) and isolated as its K(18-crown-6) salt. If the cyclic phosphane (PCF3)4 is reacted with a slight excess of K(18-crown-6)Ag P(CF3)2 2 a selective insertion of one PCF3 unit into each silver phosphorus bond is observed, giving NMR spectroscopic evidence for the Ag P(CF3)P(CF3)2 2(-) ion. On treatment of the phosphane complexes M(CO) 5PH(CF3)2 (M= Cr, W) with K(18- crown-6)Ag(CN)2 the formation of the comparable trinuclear argentates, Ag (mu P(CF3)2)M(CO)5 2(-) is achieved. The chromium compound K( 18-crown-6) Ag((mu P(CF3)2)Cr(CO)5 2 crystallizes in a non- centrosymmetric space group Fdd2 (no. 43), a = 2970.2(6) pm, b = 1584.5(3) pm, C = 1787.0(4), V = 8.410(3)cu nm, Z= 8. The C2 symmetric anion, Ag (mu-P(CF3)2) Cr(CO)5 2(-), shows a nearly linear arrangement of the P-Ag-P unit and represents the first example of a structurally characterized perfluorinated phosphanido-metal complex. Although, the bis(pentafluorophenyl)phosphanido compound Ag P(C6F5)2 2(-) could not be obtained so far, the synthesis of its trinuclear counterpart, K(18-crown-6) Ag (mu-P(C6F5)2)W(CO)5 2 was successful.