Synthesis and Reactivity of the Complexes

One of the most common routes to synthesize carbene complexes is by ligand exchange using the free carbene hgand which is in situ generated by deprotonation. Usually, the metal precursor should keep its oxidation state. However, only 

The respective Rh complex 21 (X = Cl) can be obtained without addition of halide abstractors [26]. 

The ease of oxidative addition reactions for the Rh(I)Cl complex 16 has been proven by the reaction with dichloromethane to yield complex 22 while the respective Rh(I)CO complex 21 does not show this reactivity. 

The respective Ir complex 25 could not be synthesized in pure form using [Ir(CO)(PPh3)2Cl] but it was possible with [Ir(CO)2(acac)] (acac, acetylacetonate) as metal precursor [28a]. 

KBr) [29]. This value lies in the same range as the values of the cationic complexes of Danopoulos [10, 26] bearing neutral CNC pincer ligands (1980 cm (20) and 1968 (21)). 

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Coordination Chemistry. The synthesis and reactivity of the complexes Fe2Ru(CO)i2-/ (CNBu ) and FeRu2(CO)i2- (GNBu% have also been reported." ... 

Poverenov, E. Leitus, G. Milstein, D. Synthesis and reactivity of the methylene arenium form of a benzyl cation, stabilized by complexation. J. Am. Chem. Soc. 2006, 128, 16450-16451. 

While the chemistry of metal carbonyl complexes has enjoyed a rather long and colorful history, being extensively studied and widely reviewed (7-3), the synthesis and reactivity of the group 4B (Ti, Zr, Hf) metal carbonyls have developed relatively slowly. Although the first well-characterized group 4B metal carbonyl complex, bis(i7-cyclopentadienyl)-dicarbonyltitanium (1), was reported by Murray of Monsanto Co. in... 

This chapter is intended to highlight the most important developments on the synthesis and reactivity of allenylidene complexes excluding catalytic processes. 

The most convenient method for the synthesis of lanthanide dialkyl complexes is the alkane elimination reaction of lanthanide trialkyl complexes with a monoanionic preligand (L H) (Equation 8.15). The monoanionic preligands, which have tunable steric and electronic features, are favored for modifying the stability and reactivity of the complexes. Various bulky substituted cyclopentadienyl [4] and non-cyclopentadienyl derivatives have been used as the spectator ligands. The most common types of monoanionic non-cyclopentadienyl ancillary ligands are summarized in Figure 8.10 [36 8]. 

Synthesis and reactivity of the yttrium hydride dimer [Cp Y(OAr)(/i-Fl)]2 (Ar = 2,6-Bu2C6H3) have been investigated in detail.294 295 Synthetic routes leading to tetranuclear yttrium and lutetium hydride clusters have been worked out. The complexes are accessible by reacting precursors of the type (CsMe4SiMe2R)Ln(CFI2SiMe3)2(TF[F)... 

Relatively little has appeared in the past year on the synthesis and reactivity of the six membered, potentially aromatic, phosphinine ring system. A route to the first C2-asymmetric phosphinine (147), derived from (+ )-camphor, has been developed from the reaction of a pyrylium salt precursor with P(TMS)3. The chiral phosphinine is a crystalline, air-stable solid and forms complexes with metal ions, therefore having some potential as a ligand in homogeneous eatalysis." A pyrylium salt-P(TMS)3 final step was also used in the synthesis of a series of 2-(2 -halo)triarylphosphinines (148), subsequently shown to form a series of tungsten(0) and rhodium(I) complexes involving coordination of the phosphorus sp lone pair to the metal." Interest has continued in studies of the coordination chemistry of phosphabarrelenes, derived from the established reactions of phosphinines... 

Hydrosulfido complexes, which contain M-SH groups, can react by an additional pathway unavailable to metal-thiolate complexes. Hydrosulfido complexes can react by cleavage of the S-H group to generate metal-sulfido complexes. The synthesis and reactivity of sulfido complexes are described in Qrapter 13 (metal-ligand multiple bonds). 

The synthesis and reactivity of phosphine complexes of the type [L4Ru(X)(Y)J has been an area of intense study. The syntheses of [(dmpm)2Ru(X)(Y)] (X, Y = H, alkyl, aryl) have been... 

Various reports on the synthesis and reactivity of iron complexes of trienes and tetraenes have been reported in the past 10 years. Reactivity studies of various triene and tetraene complexes predominate in the recent literature. (77-Triene)Fe(GO)3 complexes have been reported to undergo osmylation reactions with OSO4 to yield the corresponding glycols (Scheme 29). Subsequent reaction with NaI04 in THF/H20/23°C affords (dienal)Fe(GO)3 complexes. 

In a series of papers, Doherty and co-workers describe the synthesis and reactivity of allenyl complexes Fe2(GO)6(/ -RG=G=GH2)(//-PPh2) (R = H, Ph) and Fe2(GO)6(/u-HG=G=GMe2) (fx-PPhz). The parent complex, Fe2(GO)6(/ -HG=G=GH2)(//-PPh2) 102, prepared from the reaction of Na[Fe2(GO)7(//-PPh2)] with BrGH2G=GH, is the most widely utilized, and aspects of this work are summarized in Scheme It contains a highly fluxional... 

The synthesis and reactivity of the stable bis-alkyne complexes of iron, cobalt and nickel of the type [ (Ti5-C5H4SiMe3)2Ti(CCSiMe3)2 MCl2] (M = Fe, Co, Ni) has been reported . The synthesis and reactions of the related [ (T 5-C5H4SiMe3)2Hf(CCPh)2 M(CO)] (M = Co, Ni) complexes has been described . ... 

Figure 97. Synthesis and reactivity of the T) -cyclopentadienyl complex, [CpMo(NO)(ri -C,H0(S2 CNMez)].

Mills DP, Cooper OJ, McMaster J, Lewis W, Liddle ST (2009) Synthesis and reactivity of the yttrium-alkyl-carbene complex [Y(BIPM)(CH2CsH5)(THF)] (BIPM= C(PPh2NSiMe3)2)). Dalton Trans 4547 555. doi 10.1039/b902079a... 

Interest in the synthesis and reactivity of the six-membered, potentially aromatic, phosphinine ring system has also continued, but at a much lower level than in recent years. New synthetic work includes the application of the pyrylium salt route to phosphinine synthesis, this time starting from pyrylium salts bearing chiral substituents to give the related chiral phosphinines," and the development of new routes to the 2-phosphanaphthalene (137)" ° and the phosphinine-2-aldehyde (138). Also reported is an approach to the synthesis of l,2-dihydro-l,4,2-benzo-diazaphosphinines," cationic gold(I) complexes of 2,4,6-tri-t-butyl-l,3,5-triphosphabenzene," and the synthesis of some X -phosphinines from phosphonium-iodonium ylides." " ... 

Doux M, Ricard L, Mathey F, Le Floch P, Mezailles N (2003) Synthesis and reactivity of the first )7 -rhodium(l) and t -iridium(l) complexes of 2,6-bis(trimethylsilyl)phosphinines. Eur J Inorg Chem 687-698... 

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