The use of the tris (trimethylsilyl) silyl (TTMSS) group in aldehyde-derived silyl enol ethers affords aldehyde cross-aldol products with high yields and allows for unprecedented reactivity. The reaction is catalyzed by 0.05 mol% of HNTf2, and can easily be managed to give β, δ-bis-, β, δ, γ-tris-, and β, δ, ζ-tris-hydroxy-aldehydes with extremely high selectivity by simple stoichiometric control. High diastereoselectivity is obtained in all cases, and the ...
