Molybdenum chlorides

CgH Cl, is produced commercially in the Hquid phase by passing chlorine gas into benzene in the presence of molybdenum chloride at 30—50°C and atmospheric pressure. This continuous process yields a 14 1 ratio of chlorobenzene to j -dicblorobenzene [106-46-7J, The reaction of iodine with... 

X-ray diffraction, which showed that the structure of the [Tc2Cl8]2 ions is analogous to that of the isoelectronic cluster rhenium and molybdenum chlorides and bromides with a quadruple M-M bond [1,89,90] (Fig. la, Table 1). 

Impurities with catalytic effects—Impurities that act as catalysts, reducing the activation energy of a process, may increase the rate of reaction significantly, even when present in small quantities. The presence of sulfuric acid, for example, increases the rate of decomposition and decreases the observed onset temperature of various isomers of ni-trobenzoic acid [28]. Also, other substances such as NaCl, FeCl3, platinum, vanadium chloride, and molybdenum chloride show catalytic effects. As a result, the decomposition temperature can be lowered as much as 100°C. Catalysts, such as rust, may also be present inadvertently. Some decomposition reactions are autocatalyzed, which means that one of more of the decomposition products will accelerate the decomposition rate of the original substance. 

For both modern reagents PIFA and MoCls an inner-sphere radical transfer is expected, as depicted in Scheme 7. The Lewis acidic additives involved in the PIFA-mediated transformation create an iodonium species that forms a Jt-com-plex 26 with the substrate this subsequently leads to an electron transfer. In contrast, the electrophilic molybdenum chloride most probably coordinates to the oxygen atoms of the donor functions which will then start the transformation. Smooth conversions are obtained if the substituent R" adjacent to the donor (27) is another methoxy group or a bulky moiety. 

Figure 18-C-7 Preparation of molybdenum chlorides and chloro complexes.

Molybdenum chloride and dry ammonia react at a fairly low temperature with formation of ammonium chloride and a grey substance which, after extraction with water to remove ammonium and molybdenum chlorides, and warming in air, is spontaneously inflammable. The composition, however, of such a substance, or of that obtained by sublimation of molybdenum chloride with ammonium chloride, is apparently not definitely known. ... 

Magnesium chloride (MgCl) 766 Cl2MOi02(g) Molybdenum chloride oxide (M0O2CI2) 814... 

Iron chloride ((FeCl2)2) Magnesium chloride (( 6012)2) Molybdenum chloride (M0CI4)... 

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