Synfacts 2011(2): 0166-0166  
DOI: 10.1055/s-0030-1259266
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart ˙ New York

The Effect of β-Substituents in Aldol Reactions of Boron Enolates

Contributor(s): Hisashi Yamamoto, Kimberly Griffin
L. C. Dias*, E. C. de Lucca, Jr, M. A. B. Ferreira, D. C. Garcia, C. F. Tormena
Universidade Estadual de Campinas, Brazil
Further Information

Publication History

Publication Date:
19 January 2011 (online)

Significance

Traditional aldol reactions of boron enolates yield 1,5-anti diastereomers; forming the 1,5-syn diastereomer has proven to be challenging. This report describes that both PMB and TBS protecting groups of β-tert-butyl methyl ketones will result in 1,5-syn stereocontrol when reacting with an achiral aldehyde. These outcomes can be explained by theoretical calculations of transition states.