Group 8 metal-promoted oxidations alkene cleavage and asymmetric dihydroxylation

Group 8 metal-promoted oxidations alkene cleavage and asymmetric dihydroxylation 

Ligation of the metal centres can have profound effects on the chemistry of MO4 oxidations. For example, while the use of acetonitrile/water/CCl4 solvents dramatically improves the efficiency of Ru04-catalysed C-C cleavage, 

Preparation of pentanoic (valeric) acid. CsC bond cleavage by catalytically generated RUO4 

CautlonI Employ the standard precautions outlined in the introduction to this chapter for this reaction. Ruthenium tetraoxide is volatile and toxic so an efficient hood must be used. Carbon tetrachloride and sodium periodate residues are environmentally unacceptable and so every attempt should be made to recover these materials. Carbon tetrachloride should be redistilled and stored for reuse while aqueous sodium periodate residues (mostly NalOj) should be bottled for appropriate disposal. 

Clean all glassware sequentially in soap solution, water, and acetone. Allow the acetone to evaporate and then dry everything in an electric oven (105 C) for at least 1 h. 

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