Substrate-controlled stereoselectivity in the Yamamoto aldol reaction.
The Yamamoto aldol reaction is a vinylogous aldol reaction that relies on bulky aluminium-based Lewis acids. These activate both the aldehyde as well as become part of the enolate moiety. The report discloses the first detailed study on the substrate-controlled Yamamoto aldol reaction in which 2,3-syn and 2,3-anti disubstituted aldehydes serve as the stereodirecting elements. The "size" of the substituent in the β-position strongly determines the facial selectivity of enolate addition to the aldehyde. Large substituents favour formation of 1,3-syn diols while slim alkynyl groups preferentially lead to 1,3-anti products.
Institute of Organic Chemistry and Center of Biomolecular Drug Research (BMWZ), Schneiderberg 1b, 30167 Hannover.
Nadin
N
Schläger
Andreas
A
Kirschning
D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry*; D058116:Lewis Acids / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
D000438:Alcohols; D000447:Aldehydes; D058116:Lewis Acids