Small-molecule compounds asymmetric aldol reactions

Small-molecule-Catalyzed Asymmetric Aldol Reactions with Preformed Enol Ethers The methodologies of intermolecular direct asymmetric aldol reactions still tend to give mediocre results when enolizable carbonyl compounds are used. Even if current indirect small-molecule-catalyzed aldol reactions all require preactivation... 

A number of combinatorial-based syntheses have been reported. Andrus et al. prepared a solution-phase indexed combinatorial library of nonnatural polyenes such as 291 for multidrug resistance reversal.298 This library was formed by modification of R and R. Ellman and co-workers reported a combinatorial library of synthetic receptors targeting vancomycin-resistant bacteria,209 and Paterson et al. prepared polyketide-type libraries by iterative asymmetric aldol reactions on solid support.2l0 Rieser et al. used combinatorial liquid-phase synthesis to prepare [1,4]-oxazepine-7-ones by the Baylis-Hillman reaction (see sec. 9.7.B).2H Schreiber and co-workers reported the synthesis and evaluation of a library of polycyclic small molecules for use in chemical genetic assays.2 2 Bauer et al. reported a library of N-substituted 2-pyrazoline compounds... 

Reviews have featured recent applications of organocatalysts to asymmetric aldol reactions, including particular focus on catalysis by small molecules. The effects of introduction of a diaryl (oxy)methyl group into chiral auxiliaries, catalysts, and dopants have been discussed and applications of amidine-, isothiourea-, and guanidine-based nucleophilic catalysts for a range of reactions of carbonyl compounds have been highlighted. " ... 

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