Scheme 5. Stoichiometric and catalytic hydrosilylation of alkylidene cycloalkanes 4a–b, 7a–b using a molecular magnesium hydride reagent 6 (left). Proposed catalytic cycle (right). [Mg] = [Mg{CH{C(CH₃)NDipp}₂}], Dipp = 2,6-diisopropylphenyl. 16, R¹ = R² = Ph; 17, R¹ = Ph, R² = H.