Rhenium chloride

Oxidative Garbonylation. Carbon monoxide is rapidly oxidized to carbon dioxide however, under proper conditions, carbon monoxide and oxygen react with organic molecules to form carboxyUc acids or esters. With olefins, unsaturated carboxyUc acids are produced, whereas alcohols yield esters of carbonic or oxalic acid. The formation of acryUc and methacrylic acid is carried out in the Hquid phase at 10 MPa (100 atm) and 110°C using palladium chloride or rhenium chloride catalysts (eq. 19) (64,65). 

Scheme 21 Synthesis of rhenium complexes by the reaction of the rhenium chlorides with polysulfide dianions...

Pyridinedicarboxylic acid, 2696 Rhenium chloride trioxide, 4045 Rhenium hexamethoxide, 2603 Rhenium nitride tetrafluoride, 4344 Selenium dioxide, 4838... 

The correct crystal structure of the rhenium chloride complex of stoichiometry KReCL "H20 revealed a dimeric structure (Fig. 1) with three outstanding features (82). The rhenium-rhenium separation was extremely short (2.24 0.01 A), no bridging chloride ligands were present, and the two sets of four chlorides were eclipsed relative to one another when viewed down the Re—Re axis. 

Perrhenyl chloride, see Rhenium chloride trioxide, 4039 Perylenium perchlorate, 3784 1,10-Phenanthroline-5,6-dione, 3572 Phenethyl alcohol, see Benzeneethanol, 2978 Phenoxyacetylene, 2915... 

Pyridinedicarboxylic acid, 2692 Rhenium chloride trioxide, 4039 Rhenium hexamethoxide, 2599 Rhenium nitride tetrafluoride, 4338 Selenium dioxide, 4832... 

The feed is then passed through a stacked series of three or four reactors containing the catalyst (platinum chloride or rhenium chloride supported on silica or silica-alumina). The catalyst pellets are generally supported on a bed of ceramic spheres. 

A diagram showing some relationships between the rhenium(HI) and rhenium ) chlorides and complexes derived from them is given in Fig. 18-D-2. 

Up to this point, our description has been general it applies to crystals of rhenium chloride as accurately as to crystals of the ribosome. In addition to the translational symmetry (periodicity) that is inherent in the definition of a crystal, other symmetry can occur, but the kinds that can occur are restricted to crystals of biological macromolecules. Because the molecules are chiral, the symmetry operations in crystals must not change the handedness of the molecule, and so mirror planes, inversions, and glide planes (sliding mirror planes) do not occur. This leaves only rotations and screws (helical-type symmetry, sliding rotations). 

Fine Re powder is intimately ground with KCl (10% excess) and slowly heated to about 300 °C in a porcelain boat, first under Ng and then in a slow Clg stream. The KgReClg is formed immediately and only a slight quantity of rhenium chlorides is volatilized. Following cooling in a stream of Ng, the substance is dissolved in some hot 5% HCl and recrystallized the remainder is obtained by concentration and crystallization during cooling. 

Even G12-Tc-bonded complexes have been prepared. The tris(arylimido)technitium anion (90) reacted readily with 0.5 or 1 equiv. of HgBr2 to afford [Hg Tc(NAr)3 2] (91) or [BrHgTc(NAr)3] (Ar = 2,6-diisopropylphenyl) (92), respectively (Scheme 12.29) [70]. The crystal structure of Hg[Tc(NAr)3]2 shows a linear geometry around the mercury atom and the bond length of Tc-Hg is 2.615(1) A. Also the rhenium analog [Hg Re(NAr)3 2] (93) was obtained through reduction of tris(arylimido)rhenium chloride with sodium amalgam (Scheme 12.29) [70]. 

Two references deal with rhenium-chloride complexes in molten salts, specifically in molten AlCl3/methylethylimidazolium chloride. One reference reports that the half-life for reaction of [Rc3Cli2] with chloride, to give [Re2Clg] , is a few minutes at 185 the other that reaction of... 

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