Chromium-carbon bond cleavage reaction

Reaction of O2 with the complex [(H20)5CrCH(CH3)2] to give [Cr(H20)6] and acetone proceeds by a chain mechanism initiated by chromium-carbon bond cleavage with a rate of 1.74 x 10 s at 25°C and 1.0 M ionic strength. Inhibition studies suggest the organic radicals (CH3)2CH and (CH3)2CH02 are chain intermediates involved in the reaction... 

Oxidations. WChlorosuccinimide-dimethyl sulfide (NCS-DMS) is one of several reagents for converting alcohols to alkoxydtmethylsulfonium salts, which in the presence of base convert to the corresponding carbonyl compounds via intramolecular proton transfer and loss of dimethyl sulfoxide. These oxidations are among the mildest and most selective for conversions of alcohols to aldehydes and ketones. This reaction does not suffer the overoxidation to acids or the carbon-carbon bond cleavages which are often encountered in chromium(VI) or manganese(VII) oxidations (eq 1). ... 

Mikami M, Hatano M, Akiyama K (2005) Active Pd(II) Complexes as Either Lewis Acid Catalysts or Transition Metal Catalysts. 14 279-322 Minatti A, DOtz KH (2004) Chromium-Templated Benzannulation Reactions. 13 123-156 Miura M, Satoh T (2005) Catalytic Processes Involving b-Carbon Elimination. 14 1-20 Miura M, Satoh T (2005) Arylation Reactions via C-H Bond Cleavage. 14 55-84 Mizobe Y, see Hidai M (1999) 3 227-241... 

The reduction of aldols and ketols from the aldol condensation (method 102) is often a convenient route to branched 1,3-dio/s. Catalytic hydrogenation over platinum oxide, nickel-on-kieselguhr, and copper-chromium oxide has been used. Other procedures include electrolytic reduction and reduction by aluminum amalgam. 1,3-Diols may also be prepared by catalytic reduction of 1,3-diketones. Cleavage of the carbon-to-carbon and carbon-to-oxygen bonds accompanies this conversion. The effect of structure on the course of the reaction has been studied. ... 

This role of CF4 was challenged later, it being observed that its addition in small amounts quenches the sonoluminescence of chromium hexacarbonyl in silicon oil.59 contradiction however can be only apparent, since it is not established that in two very different reactions, the cleavages of a carbon-halogen and a metal-ligand bond, the mechanisms must be the same. 

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