Thallium complexes synthesis

Although LiPor-precursors are involved in the synthesis, ate complexes of type MI[LnPor2] have not been isolated, in contrast to the pyrrol derivatives [197] or charge related M [Ln(COT)2] complexes [240]. However, ternary systems are readily available by reaction of the protonated form HLnPor2 with, e.g., M OR (Eq. 16). Structural evidence has been given for the thallium complex Tl[Pr(OEP)2] [228]. 

Thallium complexes amidines, 205 phthalocyanines, 863 porphyrins, 821 triazines, 205 Thallium(I) complexes hexafluoroacetylacetone, 372 Thallium III) complexes carboxylic acids reactions, 443 1,3-diketones synthesis, 377... 

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]. ... 

A series of unsymmetric bis(pyrazolylate) ligands have been synthesized and complexed with zinc via metathesis of a thallium derivative, (17) and (18). This allowed the synthesis and complexation of NNS and NNO pyrazolylborate derivatives.1 9,160 Parkin and co-workers synthesized zinc complexes of a series of unsymmetric pyrazole-containing ligands.161-163 The asymmetric bis(pyrazolyl)hydroborato zinc complex has been structurally characterized,164 and will also be discussed in the context of its interaction with the B H hydrogen in Section 6.8.9.2. 

Oxidative phenolic coupling. Biosynthesis of the alkaloid narwedine (3) is known to involve oxidative phenolic coupling of norbelladine derivatives (1), but the usual oxidants for such coupling in vitro convert 1(R = H) into the oxomaritidine skeleton (4) rather than 3. A new biomimetic synthesis of 3 involves the palladacycle 2, formed by reaction of 1(R = CH3) with Li2PdCl4, which is known to form complexes with allylic amines or sulfides (8,176-177). Oxidation of 2 with thallium(III) trifluoroacetate effects the desired coupling to give 3. 

Most of the studies on organo-gallium, indium, and thallium porphyrin complexes have focused on synthesis and properties of the complexes, and rather little attention has been devoted to reaction chemistry. Two areas which have received some attention are the insertion of small molecules (SO2 or CO2) into the metal—carbon bonds and photochemical metal—carbon bond cleavage. The... 

Our first study of these systems was the synthesis in 1998 of the polymeric complex [ 1( 6 5)2( )2] through the reaction between triphenylphosphine oxide, thallium nitrate and lithium bis(pentafluorophenyl)aurate(I) [71]. This complex consisted of an extended unsupported linear chain of alternate gold and thallium centers. These atoms displayed Au-Tl interactions of 3.0358(8) and 3.0862(8) A, and the thallium atoms showed a distorted pseudo-trigonal-bipyramidal environment, taking into account the stereochemically active inert pair of this atom. As described below, the environment around thallium is one of the main factors that affects the optical properties of these mixed systems. 

Section II. A regioselective introduction of disilanyl bridges is necessary in the process to synthesize complexes with ligands of types 36 or 37109, and this has been made possible by methylation of the cyclopentadienyl fragments. Due to prototropic rearrangements, the protonated derivatives of 36 and 37 exist as a complicated mixture of isomers. The synthesis of the thallium derivative of 37109 is shown in equation 51. 

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