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DOI: 10.1055/s-2007-968551
Palladium-Catalyzed Asymmetric Hydroxymethylations
I. Fukuchi, Y. Hamashima, M. Sodeoka*
Tohuku University, Sendai, Japan and The Institute of Physical and Chemical Research, Wako, Japan
Publication History
Publication Date:
22 May 2007 (online)
Significance
A novel catalytic asymmetric aldol reaction of acidic carbon pronucleophiles is achieved using chiral Pd(II) and Pt(II) BINAP complexes. These hydroxymethylation reactions are possible with acyclic and cyclic β-keto esters and ketones as pronucleophiles, and highly reactive formaldehyde and ethylglyoxylate as electrophiles. Under the reaction conditions, paraformaldehyde is converted into monomeric formaldehyde, providing hydroxymethylated α-all carbon stereocenters with moderate to good yields and ee values. Direct acetylation of the product with preservation of enantioselectivity is possible by adding acetyl chloride and pyridine to the catalytic reaction, although very large excess of these reagents are required.