Enolates of Other Main Group Metals

The authors also studied the boron enolate in solution by NMR spectroscopy. 

The protons at the enolate double bond can be assigned unambiguously (Z)-proton H displays an NOE effect with the isopropyl protons, in ( )-position with the butyl group. DOSY clearly shows that the boron enolate 14 is monomeric in solution. 

The higher and elements in groups 13 and 14, thallium and lead, prefer to form the C-bound tautomers in ketone enolates [49]. 

---