Date of Award
Bachelor of Science
Chromium hexacarbonyl, Cr(C0)6, has been shown to be a very effective photochemical catalyst for many reactions, such as the 1,4- hydrogenation and 1,4-hydrosilatlon of conjugated 1,3-dienes resulting in the formation of a cis alkene product in greater than a 99% percent yield. The catalytic power of Cr(CO)6 has merited its study by many investigators, mostly with regard to the structure of the catalytic intermediates, rather than the actual kinetics of individual steps in the mechanism. The goal of this study is to construct a database of both rate and mechanistic information on the reactions of Cr(CO)6 with various alkenes and hydrosilanes. Metal carbonyls are typically very sensitive to such impurities as oxygen and water, thus it is of utmost importance that solvents be dry and degassed. The first set of experiments involved running tests on the photochemical behavior of Mn2(CO)10 in order to develop an efficient method for solvent purification. Many methods were tried, and it was discovered that refluxing over CaH2 followed by a second distillation in a fractionating column (all under flowing argon) proved to be the most effective at solvent purification. When we began flashing a system containing just Cr(CO)6 in order to reproduce literature results, it was discovered that a side reaction was occurring to form an impurity complex. Attempts to identify the impurity have so far failed, however, it does not appear to be either water
Katz, Jason David, "Flash photochemical kinetics of chromium carbonyls" (1996). Honors Theses. 2051.