Scheme 7. Inverted Chemoselectivity for Cross-Cycloadditions of Vinylsilanes with 2-Substituted-1,3-Dienes.^a.

^a Reactions conducted on 0.25 or 0.5 mmol scale. Combined isolated yields reported (with selectivity for each product listed in parentheses). ^b Reaction conducted in C₆D₆ using isoprene (13i) in place of myrcene (13j) in C₆D₆. Yield (and selectivity for hydrovinylation product 16ei) determined by integration of diagnostic ¹H NMR signals relative to an internal standard. ^c With 5 mol% [Fe] ^d Reactions conducted on 0.25 mmol scale. Conversion and product ratio determined after 24 h by gas chromatographic analysis relative to mesitylene, which was added as an internal standard at the end of the reaction. ^e 5 mol% Mg(butadiene)•2THF added as an in situ reductant. ^f Reaction performed on a 1.9 mmol scale at 200 °C for 24 h with 5 mg BHT. ^g Complex mixture of decomposition products. ^h Reactions conducted on 1.0 mmol scale. Combined isolated yields reported (with selectivity for each product listed in parentheses).