Coordination Chemistry of the cyclo‐(P₅tBu₄)⁻ Ion: Monomeric and Oligomeric Copper(I), Silver(I) and Gold(I) Complexes

Abstract

[Na{cyclo-(P(5)tBu(4))}] (1) reacts with [CuCl(PCyp(3))(2)] (Cyp=cyclo-C(5)H(9)) and [CuCl(PPh(3))(3)] (1:1) to give the corresponding copper(I) complexes with a tetra-tert-butylcyclopentaphosphanide ligand, [Cu{cyclo- (P(5)tBu(4))}(PCyp(3))(2)] (2) and [Cu{cyclo-(P(5)tBu(4))}(PPh(3))(2)] (3). The CuCl adduct of 2, [Cu(2)(mu-Cl){cyclo-(P(5)tBu(4))}(PCyp(3))(2)] (4), was obtained from the reaction of 1 with [CuCl(PCyp(3))(2)] (1:2). Compounds 2 and 3 rearrange, even at -27 degrees C, to give [Cu(4){cyclo- (P(4)tBu(3))PtBu}(4)] (5), in which ring contraction of the [cyclo-(P(5)tBu(4))](-) anion has occurred. The reaction of 1 with [AgCl(PCyp(3))](4) or [AgCl(PPh(3))(2)] (1:1) leads to the formation of [Ag(4){cyclo-(P(4)tBu(3))PtBu}(4)] (6). Intermediates, which are most probably mononuclear, "[Ag{cyclo-(P(5)tBu(4))}(PR(3))(2)]" (R=Cyp, Ph) could be detected in the reaction mixtures, but not isolated. Finally, the reaction of 1 with [AuCl(PCyp(3))] (1:1) yielded [Au{cyclo-(P(5)tBu(4))}(PCyp(3))] (7), whereas an inseparable mixture of [Au(3){cyclo-(P(5)tBu(4))}(3)] (8) and [Au(4){cyclo-(P(4)tBu(3))PtBu}(4)] (9) was obtained from the analogous reaction with [AuCl(PPh(3))]. Complexes 3-7 were characterised by (31)P NMR spectroscopy, and X-ray crystal structures were determined for 3-9.

The unusual coordination chemistry of phosphorus-rich linear and cyclic oligophosphanide anions

“…In view of the results obtained in the reactions of [Na(thf) 4 ][cyclo-(P 5 Bu t 4 )] (39) with complexes of the nickel triad, the coordination chemistry of the cyclo-(P 5 Bu t 4 ) − ion towards group 11 complexes was explored. Here, it was also observed that the reactivity of the cyclic anion is notably dependent on the metal, its co-ligands and the reaction conditions [58].…”

“…Low-temperature 31 the metal, resulting in trigonal-planar copper complexes 75 and 76 and linear gold complex 80 (Fig. 24) [58]. In 77, the P 5 ring bridges a Cu 2 Cl fragment via the anionic and an adjacent phosphorus atom.…”

“…6(3) [Pt(P4Mes4)(C NBu t )2] (57) 221.3(2) 231. 9(1) g [50] 221.3 (2) 233.9(1) 222.1 (2) [Pt(P4Mes4)(C NCy)2] (58) 221.1(2) 233.1 (2) g [50] 221. 2(2) 233.1(2) 221.5 (2) [Na(thf)3][Rh(P3Mes3)(cod)] (59) 221.4 (2) 299.9 (2) [53] 213.4(4) 219.5(2) j 213.…”

“…6(1) f [58] 220.5 (2) 221.0(1) 221.5 (2) 227.3(1) 221.8 (2) 223 . (7) a Regular P-P bonds of the P5 ligand. b Short P-P bond of the P5Bu t 4 ligand due to interaction of the lone pair of electrons at the anionic phosphorus atom with unoccupied orbitals (with *-and d-orbital contributions) at the adjacent phosphorus atom.…”

“…The two copper atoms have a trigonal-planar environment (Fig. 25) [58]. Both copper atoms are nearly coplanar with the two phosphorus atoms of the PCyp 3 ligands (P(6) and P (7)).…”