Picolylamine as an organocatalyst template for highly diastereo- and enantioselective aqueous aldol reactions.

نویسندگان

  • Thomas C Nugent
  • M Naveed Umar
  • Ahtaram Bibi
چکیده

A pyridine based 1,2-diamine containing only one stereogenic center has been identified for fast aldol reactions (16-48 h). Using 2-5 mol% of (R)- or (S)-PicAm-2, cyclohexanone (3.3 equiv) readily undergoes aldol reactions with o-, m-, and p-substituted aromatic aldehyde partners (limiting reagent), including the poor electrophile 4-methylbenzaldehyde (95-99% ee). Furthermore, functionalized cyclic ketone substrates have been converted into four aldol products 9-12 using the lowest catalyst loading (5.0 mol%) to date with the highest yield and enantioselectivity.

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عنوان ژورنال:
  • Organic & biomolecular chemistry

دوره 8 18  شماره 

صفحات  -

تاریخ انتشار 2010