Ringing the changes: The 5-exo-trig cyclization pathway of γ-allenols can be completely reversed by either changing the metal (Pd instead of Au) or using a (methoxymethyl)oxy protecting group. As a result, the 7-endo-trig alkoxycyclization dominates instead (see scheme; MOM=MeOCH2; Z1=tBuMe2Si, ArCO).
No takes yet. Share an insight, caveat, or question.
Alcaide et al. (2007) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: