Angewandte
Chemie
pentadienyl)(dimethylaluminum)titanium, Teoc = 2-(trimethyl-
silyl)ethoxycarbonyl, TES = triethylsilyl, Tf = trifluoromethane-
sulfonyl, TIPS = triisopropylsilyl, TMS = trimethylsilyl, Ts = p-
toluenesulfonyl.
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experiments, thus suggesting
duringthe cycloaddition.
a stepwise reaction pathway
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