Phosphorus and arsenic donor ligands

Complexes of the type [PdX L] (X = Cl, Br, I, or SCN) and PdL Y (Y = Cl, Br, I, SCN, or CIO ) have been prepared with the hybrid ligands (68)—(70). I.r. data confirm that the [PdX2L] compounds are square-planar with bidentate L. However, depending on the nature of Y, the PdL Yj species exhibit a variety of four-, five-, and six-co-ordinate forms containing both bidentate and unidentate (As bonded) hybrid ligands.  

Chiswell, R. A. Plowman, and K. Verrall, Inorg. Chim. Acta, 1972, 6, 275. 

Similar, but more extensive, studies of the co-ordination behaviour of the bifunctional ligands (70a) and (70b) with a range of metals have revealed both P,N and P,P bonding. For the Pd complexes [PdXjL] (X = Cl, Br, or I), i.r. data indicate that both ligands employ P,P co-ordination. The choice of donor atom is discussed in terms of chelate ring size and stereochemical preferences of the various metals.  

Complexes of the type [PdXjL]X (X = Cl, Br, I, CNS, or CN L = Et2PC2H4.PEt2) have been prepared as part of a survey to determine the factors favouring five-co-ordination. Unlike some similar Ni complexes, these were four-co-ordinate square-planar. The thiocyanate complex was shown (i.r.) to contain both N- and S-bonded CNS.  

The extended series [PdX Crac-diars)] and [PdX2(meso-diars)] (X = Cl, Br, or I) have been synthesized using the method previously employed for the chloro-complex. Their configurations were confirmed from n.m.r. and i.r. data. Also reported are the five-co-ordinate compounds [PdXL] [(X = Cl, Br, I, or SCN L = (71a)]. Trigonal-bipyramidal geometry was indicated 

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Reactions with Phosphorus and Arsenic Donor Ligands... 

Table 2.27. Limiting first-order rate constants for the substitution reactions of Os3(CO)u(NCMe) with phosphorus and arsenic donor ligands...

Ph, Me) using polydentate phosphorus- and arsenic-donor ligands... 

A variety of phosphinoacetylenes has been prepared by reaction of an acetylene and a chlorophosphine in the presence of butyl-lithium. The synthesis of several quadridentate ligands containing both phosphorus and arsenic donor atoms, e.g (3), from a chlorophosphine and the appropriate lithio-derivative has been described. ... 

Phosphorus and Arsenic Donors. 8.1 Monodentate ligands. 8.2 Polydentate ligands... 

C. A. McAuliffe and W. Levason, Phosphine, Arsine and Stibine Complexes of the Transition Elements, Elsevier, Amsterdam, 1979, 546 pp. A review with over 2700 references. See also C. A. McAuliffe (ed,), Transition-Metal Complexes of Phosphorus, Arsenic and Antimony Donor Ligands, Macmillan, London, 1972,... 

S.2.4.2.4. Complexes of Mercury(l) with Phosphorus-, Arsenic-and Antimony-Donor Ligands. 

Platinum(II) Complexes with Phosphorus-, Arsenic-, and Antimony-donor Ligands 706... 

Phosphorus, arsenic, and antimony donor ligands. A general synthesis has been reported for trialkyl phosphite complexes of noble metals, including [RuLeJ, [RuXLsl, and [RuHLs]+ [L = P(OMe)3 or P(OEt)3 X = Cl or Br]. The complexes were isolated as their tetraphenylborate salts from reaction of the phosphite with methanolic solutions of suitable labile olefin... 

COMPLEXES OF GOLD(I) WITH PHOSPHORUS, ARSENIC AND ANTIMONY DONOR LIGANDS... 

Transition-metal complexes of Phosphorus, Arsenic, and Antimony Donor Ligands , ed. C. A. McAuliffe. McMillan, London, 1973. 

S. D. Robinson Transition metal complexes containing phosphorus, arsenic, antimony and bismuth donor ligands. 

Tetracarbonyl cations [Cr(CO)4(L2)]+, where L2 represents arylphosphines, alkyl, or aryl phosphites, or a bidentate ligand with phosphorus or arsenic donor atoms, have been produced by both chemical and electrochemical means. However, oifly one of these complexes, namely, tra i -[Cr(CO)4(PPh3)2]+, is stable enough to be isolated as the perchlorate salt. Exposure to light and moisture produces tra i -Cr(CO)4(PPh3)2 via disproportionation. Just as easily isolated, but somewhat less sensitive, are the [Cr(CO)3(PR3)3]+ cations. " Oxidation with a silver ion or NO+ converts the /uc-(R3 = Me2Ph, (OMe)3) and mer-(R3 = (OMe)3, (OMe)2Ph, (OPh)3) complexes into Cr products with mer structures. Light and heat promote the formation of reduced wer-Cr(CO)3 (PR3)3. These tetra(carbonyl) and tri(carbonyl) cations have been the subject of ESR spectroscopy and theoretical study. 

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