Fig. 5. Enhancing the selectivity of anti-hydrozirconation by leveraging a postulated n_S → Zr interaction. Reaction conditions: (i) Cp₂ZrHCl (62 mg, 0.24 mmol, 1.2 eq.), CH₂Cl₂ (1.5 mL), alkyne A-22-24 (0.2 mmol, 1.0 eq.) in CH₂Cl₂ (0.5 mL), rt, 15 min; (ii) irradiation (λ = 400 nm), 45 min; (iii) NBS (39 mg, 0.22 mmol, 1.1 eq.), rt, 15 min.