Elizabeth, I think the observed products should come as no surprise. If toluene was allowed to sit in a less than perfectly sealed container for a number of years, the three hydrogens on the Methyl might be expected to get restless and do what comes naturally! That is - form Resonance stabilized Radicals. Such an Intermediate will also explain all three products you report, and also suggest that the hydroperoxide was the first product of the reaction of air ( about 20% oxygen right? ) with toluene. If that compound then decomposes by scission of the O-O bond, as peroxides are known to do, the stage is set to pick up a H atom on oxygen and form Benzyl alcohol. Where might that H come from? Well if it came from the alpha-C-H bond of another benzyloxy radical, it would form benzaldehyde. Organic Chemistry can be a help, as well as the pain that too many of us remember from poorly taught undergraduate courses. Best Wishes! George Wahl On Jul 9, 2007, at 4:03 PM, Elizabeth Gregory wrote: > Hi everyone, > > Our department finally opened up a 5 gallon metal drum of toluene > earlier > this summer. The drum is somewhere between 6 and 20 years old (you can > imagine why I wanted to see it used up...). > > After a couple of days of "what the %**At_Symbol_Here** is this reaction by- > product?!", > we've finally figured out that the toluene itself has the following > impurities: benzaldehyde, benzyl alcohol, and benzyl hydroperoxide > (!!!). The > total concentration of these impurities is about 240 mg/L of solution. > > Has anyone ever heard of toluene forming these products while it's > left > sitting around unopened? This is a new one, both to me and our > resident > organic chemist. > > Elizabeth Gregory > Laboratory Manager > Department of Chemistry > SUNY College at Brockport > Room 230 Smith Hall > Brockport, NY 14420 > (585) 395-2210 > Fax: (585) 395-5805 > Email: egregory**At_Symbol_Here**brockport.edu >
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