Transition Metal Complexes with

Tin(ll) chloride, SnCl2, stannous chloride. M.p. 247 - C. While solid (Sn plus gaseous HCl), forms hydrates (SnCl2,2H20 is tin salt) from Sn and aqueous HCl. Acts as acceptor in complexes and forms complexes with transition metals. Used as a mordant. 

Phosphite triesters, P(OR)3, form donor complexes with transition metals and other acceptors and are oxidized to the respective phosphates under appropriate conditions. 

Thiocyanates are rather stable to air, oxidation, and dilute nitric acid. Of considerable practical importance are the reactions of thiocyanate with metal cations. Silver, mercury, lead, and cuprous thiocyanates precipitate. Many metals form complexes. The deep red complex of ferric iron with thiocyanate, [Fe(SCN)g] , is an effective iadicator for either ion. Various metal thiocyanate complexes with transition metals can be extracted iato organic solvents. 

Aminoboranes have been used as ligands in complexes with transition metals (66) in one instance giving a rare example of two-coordinate, non-t/ transition-metal complexes. The molecular stmcture of the iron complex Fe[N(Mes)B(Mes)2]2 where Mes = is shown in Figure 1. The... 

The Schiff basses derived from salicylaldehydes polydentate ligands ai e known to form very stable complexes with transition metal ions [1]. 

Zincon disodium salt (o-[l-(2-bydroxy-5-sulfo)-3-pbenyl-5-formazono]-benzoic acid di-Na salt) [135-52-4, 56484-13-0] M 484.4, m -250-260 (dec). Zincon soln is prepared by dissolving 0.13g of the powder in aqueous N NaOH (2mL diluted to lOOmL with H2O). This gives a deep red colour which is stable for one week. It is a good reagent for zinc ions but also forms stable complexes with transition metal ions. [UV-VIS Bush and Yoe Anal Chem 26 1345 1954 Hunter and Roberts J Chem Soc 820 1941 Platte and Marcy Anal Chem 31 1226 1959] The free acid has been recrystd from dilute H2SO4. [Fichter and Scheiss Chem Ber 33 751 1900.]... 

The combination of hard (A) and soft (5) coordination in the 1,5-P2N4S2 ring system leads to a diversity of coordination modes in complexes with transition metals (Lig. 13.1). In some cases these complexes may be prepared by the reaction of the dianion [Ph4P2N4S2] with a metal halide complex, but these reactions frequently result in redox to regenerate 13.3 (L = S, R = Ph). A more versatile approach is the oxidative addition of the neutral ligand 13.3 (L = S) to the metal centre. 

Periodates form numerous complexes with transition metals in which the octahedral unit acts as a bidentate chelate. Examples are ... 

Whereas Cu and Ag form complexes with derivatives of transition-metal carbonyls in which the Cu or Ag are 4 coordinated in both the reactant and in the final product, many analogous Au complexes exhibit only 2 coordination. For example, the simple Au complex Ph3PAuCI reacts with transition-metal carbonyl anions in THF to give complexes with transition-metal to Au bonds, e.g. ... 

Beside complexation with transition-metals, PAM 4 exhibited unusual chemistry when treated with an alkali metal. Addition of four equivalents of lithium... 

Base-stabilized stannylenes have been known to form complexes with transition metals before stable stannylenes were detected. They are synthesized by a reaction similar to process (17) or by reduction of Sn(IV) compounds according to Eq (23) 146) ... 

Despite the volume of work concerned with metal-catalyzed decomposition of diazo compounds and carbenoid reactions 28>, relatively little work has been reported on the metal-catalyzed decomposition of sulphonyl azides. Some metal-aryl nitrene complexes have recently been isolated 29 31>. Nitro compounds have also been reduced to nitrene metal complexes with transition metal oxalates 32K... 

The S02 molecule has unshared pairs of electrons on both the sulfur and oxygen atoms. As a result, it forms numerous complexes with transitions metals in which it is known to attach in several ways. These include bonding through the sulfur atom, through an oxygen atom, by both oxygen atoms, and various bridging schemes. In most cases, the complexes involve soft metals in low oxidation states. Another important reaction of sulfur dioxide is known as the insertion reaction, in which it is placed... 

Some representative co-facial systems. The series (138)—(140) of mixed thiaaza donor ligands have been synthesized and all three have been shown to form binuclear complexes with transition metal ions (Lehn, 1980). In these, each metal ion is associated with one cyclic subunit as shown in (141) for (138). Complexes containing two Cu(n) ions or two Cu(i) ions have been obtained with each of (138)-(140) while (139), the... 

The macrocycle types discussed so far tend to form very stable complexes with transition metal ions and, as mentioned previously, have properties which often resemble those of the naturally occurring porphyrins and corrins. The complexation behaviour of these macrocycles contrasts in a number of ways with that of the second major category of cyclic ligands - the crown polyethers. 

Heterometallic alkali metal phosphide complexes with transition metals have also been reported. The complex [(Cy2P)3Hf(ju.-PCy2)2Li (DME)] results from the reaction of LiPCy2 with HfCl4(THF) (98). This complex persists in solution. Jones et al. have reported the synthesis and reactivity toward a range of electrophiles of a series of lithium di-t-butylphosphido(alkyl)cuprates [RCu(PBu2)Li] (R = Me,... 

Table 8 Monovalent chelated Ga+ and ln+ complexes with transition metal fragments...

Boron. Earlier papers reviewed the properties of the borabenzene anion and discussed its potential aromaticity.130 182 A few examples have been shown in Schemes 31 and 53. The borabenzene anion (borinate) 141, with R = phenyl or methyl, gives complexes with transition metals such as Co (142) and Mn (143) (Scheme 61).183 Aza- and polyaza-... 

Heteroatom-disubstituted carbenes form stable complexes with transition metals these have not yet found broad application in organic synthesis. The use of these complexes as catalysts for various transformations is being investigated [153,175,274,275]. 

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