| Abstract
| - Described are among the first highly diastereoselective, one-pot organometallic addition and hydride reduction reactions(>95% de) involving three symmetry-equivalent carbonylcenters, each that bears a 1,5-relationship to its nearestneighbor. Three-fold methyllithium addition to 2,4,6-trimethoxybenzene-1,3,5-tricarbaldehyde gives the anti,syn triolexclusively (by 1H NMR); addition of HMPA to the reactionor replacement of the substrate's methoxy groups with ethylgroups affords a statistical 3:1 (anti,syn:syn,syn) diastereomeric product ratio. Analogous asymmetric induction isfound upon hydride reduction (using LiAlH4 or NaBH4) ofthe complementary triketone, 2,4,6-trimethoxybenzene-1,3,5-triethanone. Chelation and steric (gearing) effects about thecrowded aromatic core contribute to the observed stereoselectivity.
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