Iron(II) and Zinc(II) Complexes with Designed pybox Ligand for Asymmetric Aqueous Mukaiyama‐Aldol Reactions.

Abstract

Alcohols Q 0230 Iron(II) and Zinc(II) Complexes with Designed pybox Ligand for AsymmetricAqueous Mukaiyama-Aldol Reactions. -The Fe and Zn catalysts efficiently promote the reaction of aliphatic and aromatic aldehydes. However, coupling of the pyridinealdehyde (VI) leads to a racemic product. -(JANKOWSKA, J.; PARADOWSKA, J.; RAKIEL, B.; MLYNARSKI*, J.; J. Org. Chem. 72 (2007) 6, 2228-2231; Inst. Org. Chem., Pol. Acad. Sci., PL-01-224 Warsaw, Pol.; Eng.) -Jannicke 30-054

Zinc-prolinamide complex catalyzed direct asymmetric aldol reactions in the presence of water

“…An enamine was presumed to be formed in the active site. These results were also demonstrated by Mlynarski group's previous work [35].…”

“…Because of water's unique physical and chemical properties compared with regular organic solvents, few satisfactory asymmetric aldol reactions in aqueous media were reported, except for several zinc complexes offering promising results [33][34][35]. Apparently, direct asymmetric aldol reactions in aqueous media remain a great challenge.…”