Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.


Originally published in Science Express on 29 March 2007
Science 27 April 2007:
Vol. 316. no. 5824, pp. 582 - 585
DOI: 10.1126/science. 1142696

Reports

Enantioselective Organocatalysis Using SOMO Activation

Teresa D. Beeson,1,2 Anthony Mastracchio,1,2 Jun-Bae Hong,1,2 Kate Ashton,1,2 David W. C. MacMillan1,2*

The asymmetric {alpha}-addition of relatively nonpolar hydrocarbon substrates, such as allyl and aryl groups, to aldehydes and ketones remains a largely unsolved problem in organic synthesis, despite the wide potential utility of direct routes to such products. We reasoned that well-established chiral amine catalysis, which activates aldehydes toward electrophile addition by enamine formation, could be expanded to this important reaction class by applying a single-electron oxidant to create a transient radical species from the enamine. We demonstrated the concept of singly occupied molecular orbital (SOMO) activation with a highly selective {alpha}-allylation of aldehydes, and we here present preliminary results for enantioselective heteroarylations and cyclization/halogenation cascades.

1 Merck Center for Catalysis, Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
2 Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.

* To whom correspondence should be addressed. E-mail: dmacmill{at}princeton.edu

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Merging Photoredox Catalysis with Organocatalysis: The Direct Asymmetric Alkylation of Aldehydes.
D. A. Nicewicz and D. W. C. MacMillan (2008)
Science 322, 77-80
   Abstract »    Full Text »    PDF »



To Advertise     Find Products


Science. ISSN 0036-8075 (print), 1095-9203 (online)