Complex with mercury dichloride

Complex [(CXI )Ir(/j,-pz)(/i,-SBu )(/j,-Ph2PCH2PPh2)Ir(CO)] reacts with iodine to form 202 (X = I) as the typical iridium(II)-iridium(II) symmetrical species [90ICA(178)179]. The terminal iodide ligands can be readily displaced in reactions with silversalts. Thus, 202 (X = I), upon reaction with silver nitrate, produces 202 (X = ONO2). Complex [(OC)Ir(/i,-pz )(/z-SBu )(/i-Ph2PCH2PPh2)Ir(CO)] reacts with mercury dichloride to form 203, traditionally interpreted as the product of oxidative addition to one iridium atom and simultaneous Lewis acid-base interaction with the other. The rhodium /i-pyrazolato derivative is prepared in a similar way. Unexpectedly, the iridium /z-pyrazolato analog in similar conditions produces mercury(I) chloride and forms the dinuclear complex 204. 

The formed mercury dichloride is separated as a crystalline complex with dioxane. Since the starting arylmercury chlorides are easily prepared from diazonium salts, this method allows the conversion of anilines into aryltellurium trichlorides. 

Chlorophenyl Tellurium Trichloride1 A 100 ml one-necked flask is fitted with a reflux condenser carrying a calcium chloride drying tube and charged with 2.7 g (10 mmol) of tellurium tetrachloride, 3.5 g (10 mmol) of 4-chlorophenyl mercury chloride, and 30 ml of dry dioxane. The mixture is heated under reflux for 4 h, cooled to 20 , the mercury dichloride/dioxane complex is filtered off, and the filtrate is distilled under vacuum. The residue is recryslallized from glacial acetic acid yield 3.3 g (96%) m.p. 225°... 

The reader may remember that the 77-complex structure for the adducts formed from acetylene and mercury dichloride, or of related complexes of non-transitional-metal halides, was disproved by our stereochemical investigations. The true 77-complexes, however, were also obtained by us from tolan and the derivatives of such transition metals as V, Nb, and Ta (451-455). 77-Cyclopentadienylniobium tetracarbonyl reacted with tolan according to the scheme shown on page 57. 

Fig. 2 Chromatogram of a standard mixture after complexation with sodium diethyldithiocarbamate. Composition of the standard mercury dichloride, methylmercury chloride, ethylmercury chloride, methoxyethylmercury chloride, ethoxyethylmercury chloride, phenylmercury chloride, and tolymercury chloride.

Triethylamine in THF can be used as the external base to deprotonate triazolium salts. The resulting NHCs were complexed in situ, e.g., to [(/7 -cymene)RuCl2]2, [(/ -cod)RhCl]2, and [(/ -C5Me5)RhCl2]2. Sodium carbonate in water/ DMSO deprotonates imidazolium iodides in the presence of mercury(II) dichloride to give [Hg(NHC)2][Hgl3Cl]. " A pyridine-functionalized imidazolium salt was deprotonated by lithium diisopropylamide (LDA) in THF and attached in situ to [(p -cod)Pd(Me)Br] [Eq.(17)]. After abstraction of the bromide anion with silver(I) a tetranuclear ring is formed. 

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