Asymmetric syn-Aldol Reaction of alpha-Hydroxy Ketones with Tertiary Amine Catalysts

作者：Bas Sebastian; Wozniak Lukasz; Cygan Judyta; Mlynarski Jacek^*

来源：European Journal of Organic Chemistry, 2013, 2013(30): 6917-6923.

DOI：10.1002/ejoc.201300872

• Asymmetric synthesis
• Organocatalysis
• Aldol reactions
• Alkaloids

The tertiary amine-catalyzed direct asymmetric aldol reaction of 2-hydroxyacetophenones (2-hydroxy-1-arylethanones) with a variety of aliphatic aldehydes has been demonstrated. By using 20 mol-% of unmodified cinchonine as catalyst, the direct aldol reaction products were isolated in good yields and with remarkably high syn diastereocontrol and good asymmetric induction (40-78% ee). This newly elaborated tertiary-amine-catalyzed direct asymmetric aldol reaction has extended the scope of organocatalytic processes to aromatic alpha-hydroxy ketones, which have hitherto been unreactive towards enamine catalysis.

• 出版日期2013-10