I/ - complexes, synthesis

Williams, D.B.G., Traut, T, Kriel, F.H. and van Zyl, W.E. (2007) Bidentate amino-and iminophosphine ligands in mono-and dinuclear gold(I) complexes Synthesis, structures and AuCl displacement by AuC E . Inorganic Chemistry Communications, 10(5), 538-542. 

FIGURE 3.6 A picture of (U-mesityl)Au 5. (Data from A homoleptic arylgold(I) complex synthesis and structure of pentanuclear mesitylgold(I). S. Gambarotta, C. Floriani, A. Chiesi-Villa, and C. Guastini, Chem. Commun., 1983, 1304.)... 

I ovolac Synthesis and Properties. Novolac resins used in DNQ-based photoresists are the most complex, the best-studied, the most highly engineered, and the most widely used polymers in microlithography. Novolacs are condensation products of phenoHc monomers (typically cresols or other alkylated phenols) and formaldehyde, formed under acid catalysis. Figure 13 shows the polymerization chemistry and polymer stmcture formed in the step growth polymerization (31) of novolac resins. 

Introduction of the cobalt atom into the corrin ring is preceeded by conversion of hydrogenobyrinic acid to the diamide (34). The resultant cobalt(II) complex (35) is reduced to the cobalt(I) complex (36) prior to adenosylation to adenosylcobyrinic acid i7,i -diamide (37). Four of the six remaining carboxyhc acids are converted to primary amides (adenosylcobyric acid) (38) and the other amidated with (R)-l-amino-2-propanol to provide adenosylcobinamide (39). Completion of the nucleotide loop involves conversion to the monophosphate followed by reaction with guanosyl triphosphate to give diphosphate (40). Reaction with a-ribazole 5 -phosphate, derived biosyntheticaHy in several steps from riboflavin, and dephosphorylation completes the synthesis. 

The synthesis and characterization of the monomeric amidinato-indium(I) and thallium(I) complexes [Bu C(NAr)2]M[But(NAr(NHAr)] (M = In, Tl Ar = 2,6-Pr2CgH3) have been reported. Both compounds were isolated as pale yellow crystals in 72-74% yield. These complexes, in which the metal center is chelated by the amidinate ligand in an N, j -arene-fashion (Scheme 33), can be considered as isomers of four-membered Group 13 metal(I) carbene analogs. Theoretical studies have compared the relative energies of both isomeric forms of a model compound, In[HC(NPh)2]. ... 

Sodium borohydride reductions of gold(I) complexes give Au clusters at RT if sodium borohydride in ethanol is dropped slowly into a suspension of the Au(I) complex in the same solvent. The immediate coloring of the reaction mixture (mostly red), even after only a few drops of the borohydride have been added, indicates fast formation of Au clusters. In view of the complicated composition of these compounds the fast formation is surprising. The use of H2 and CO with HjO as reducing agents in the synthesis of gold clusters has been described (see Table 1, Method A, 8.2.2.2). 

The enantioselective 1,4-addition addition of organometaUic reagents to a,p-unsaturated carbonyl compounds, the so-called Michael reaction, provides a powerful method for the synthesis of optically active compounds by carbon-carbon bond formation [129]. Therefore, symmetrical and unsymmetrical MiniPHOS phosphines were used for in situ preparation of copper-catalysts, and employed in an optimization study on Cu(I)-catalyzed Michael reactions of di-ethylzinc to a, -unsaturated ketones (Scheme 31) [29,30]. In most cases, complete conversion and good enantioselectivity were obtained and no 1,2-addition product was detected, showing complete regioselectivity. Of interest, the enantioselectivity observed using Cu(I) directly in place of Cu(II) allowed enhanced enantioselectivity, implying that the chiral environment of the Cu(I) complex produced by in situ reduction of Cu(II) may be less selective than the one with preformed Cu(I). 

A novel chiral dissymmetric chelating Hgand, the non-stabiUzed phosphonium ylide of (R)-BINAP 44, allowed in presence of [Rh(cod)Cl]2 the synthesis of a new type of eight-membered metallacycle, the stable rhodium(I) complex 45, interesting for its potential catalytic properties (Scheme 19) [81]. In contrast to the reactions of stabihzed ylides with cyclooctadienyl palladium or platinum complexes (see Scheme 20), the cyclooctadiene is not attacked by the carbanionic center. Notice that the reactions of ester-stabilized phosphonium ylides of BINAP with rhodium(I) (and also with palladium(II)) complexes lead to the formation of the corresponding chelated compounds but this time with an equilibrium be-... 

Archibald, S.J., Alcock, N.W., Busch, D.H. and Whitcomb, D.R. (2000) Synthesis and characterization of silver(I) complexes with C-AIkyl functionahzed N,f/-Diphenylamidrnates Tetrameric and trrmeric structural motifs. Journal of Cluster Science, 11, 261—283. 

Abdou, H. (2006) PhD. Thesis New Chemistry with Gold-Nitrogen Complexes Synthesis and Characterization of Tetra-, Tri-, and Dinuclear Gold(I) Amidinate Complexes. Oxidative-Addition to the Dinuclear Gold (I) Amidinate, A M University, Texas. 

Forward, J.M., Fackler, J.P. and Staples, R.J. (1995) Synthesis and structural characterization of the luminescent Gold(I) Complex [(MeTPAJjAulJIj. Use of NaBPha as a phenyl transfer reagent to form [(MeTPA)AuPh](BPh4) and (TPA) AuPh. Organometallics, 14, 4194—4198. 

Cronje, S., Raubenheimer, H.G., Spies, H.S.C., Esterhuysen, C., Schmidbaur, H., Schier, A. and Kruger, G.J. (2003) Synthesis and characterisation of N-coordinated pentafluorophenyl gold(I) thiazole-derived complexes and an unusual self-assembly to form a tetrameric gold(I) complex. Dalton Transactions, (14), 2859-2866. 

Ade, A., Cerrada, F., Contel, M., Laguna, M., Merino, P. and Tejero, T. (2004) Organometallic gold(III) and gold(I) complexes as catalysts for the 1,3-dipolar cycloaddition to nitrones synthesis of novel gold-nitrone derivatives. Journal of Organometallic Chemistry, 689(10), 1788-1795. 

Bardaji, M Laguna, A., Jones, P.G. and Fischer, A.K. (2000) Synthesis, Structural Characterization of Luminescent Trinuclear Gold(I) Complexes with Difhiocarbamates. Inorganic Chemistry, 39(16), 3560-3566. 

Uson, R., Fomies, J., Laguna, A. and Valenzuela, J.I. (1982) Pseudohalo-bridged pentafiuorophenyl gold-palladium complexes. Synthesis and Reactivity in Inorganic and Metal-Organic Chemistry, 12(7), 935-946. 

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