Retrodiene cleavage

Despite the calculated, rather low first ionization potential, suggesting an isolated, easy-to-detect band in the silaethene PE spectrum, numerous pyrolysis experiments with promising precursors, such as 1,3-disilacyclobutane, yielded no reproducible PE band in the expected region. Eventually, in the thermal retrodiene cleavage of a 5,6-bis(trifluoromethyl) derivative of 2-silabicyclo[2.2.2]octa-5,7-diene, a novel band exhibiting vibrational fine structure appeared within the precalculated region (Figure 4). 

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