Attention:

Certain features of Sigma-Aldrich.com will be down for maintenance the evening of Friday August 18th starting at 8:00 pm CDT until Saturday August 19th at 12:01 pm CDT.   Please note that you still have telephone and email access to our local offices. We apologize for any inconvenience.

Asymmetric Allylation Using COP Catalysts

By: William Sommer, Aldrich ChemFiles 2008, 8.6, 6.

Aldrich ChemFiles 2008, 8.6, 6.

Chiral allylic aryl esters are valuable building blocks for the synthesis of natural products and drug candidates. In recent years, several research groups developed new catalysts to synthesize chiral allylic esters from phenols and prochiral allylic precursors.1 Overman and co-workers developed a new method to synthesize chiral 3-aryloxy-1-alkenes using COP-OAc catalysts.2 This reaction only requires 1 mol% of catalyst producing the desired product in high yields and high ee’s (Scheme 1). A library of alllylic trichloroacetimidates and phenols were screened. This new method is compatible with the presence of base-labile functionality.


Scheme 1.

back to top 

Materials

     

References

  1. (a) Trost, B. et al. J. Am. Chem. Soc. 2005, 127, 7014. (b) Mbaye, M. D. Et al. Chem. Commun. 2004, 1870. (c) Shekhar, S. et al. J. Am. Chem. Soc. 2006, 128, 11770.
  2. Kirsch, S. F. Et al. Org. Lett. 2007, 9, 911.

back to top 

Related Links

Categories