Picolylamine as an organocatalyst template for highly diastereo- and enantioselective aqueous aldol reactions.
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.
Nugent
Thomas C
TC
Department of Chemistry, School of Engineering and Science, Jacobs University Bremen, Campus Ring 1, 28759 Bremen, Germany. t.nugent@jacobs-university.de
Umar
M Naveed
MN
Bibi
Ahtaram
A
D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry*; D002384:Catalysis; D003959:Diamines / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D010847:Picolines / Q000737:chemistry*; D013237:Stereoisomerism; D014867:Water / Q000737:chemistry
D000438:Alcohols; D000447:Aldehydes; D003959:Diamines; D007659:Ketones; D010847:Picolines; D014867:Water