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Chemical Synthesis

Chiral Phosphoric Acids: Versatile Organocatalysts with Expanding Applications

Introduction
Advantages
Representative Applications
Product Information

Introduction

We are proud to offer a suite of BINOL-derived chiral phosphoric acids in our collection of products for asymmetric catalysis. This well established class of chiral Brønsted acid catalysts has been applied to an ever-increasing number of useful transformations.

Advantages

  • Alternative to metal catalysts and chiral auxiliaries
  • Both enantiomers of catalyst are available
  • Relatively low catalyst loading (often 1-5 mol %)
  • High selectivity at non-cryogenic reaction temperatures (-30 to 23 °C)


Representative Applications

Reductive Amination
One of the earliest demonstrations of chiral phosphoric acid catalysis is the metal-free reduction of imines with an organic reductant (Hantzsch ester) to give enantioenriched amines.1


Allylation

The enantioselective allylation of aldehydes can be accomplished under very mild conditions at non-cryogenic temperature (-30 °C).2


Friedel-Crafts Alkylation

Functionalized indoles3,4 and pyrroles5 can be accessed in enantioenriched form by asymmetric alkylation.


Product Information

View the complete Chiral Phosphoric Acids product portfolio.


References

  1. (a) Rueping, M.; Sugiono, E.; Azap, C.; Thiessman, T.; Bolte. M. Org. Lett. 2005, 7, 3781. (b) Hoffmann, S.; Seayad, A.; List, B. Angew. Chem. Int. Ed. 2005, 44, 7424. (c) Storer, R. I.; Carrera, D. E.; Ni, Y.; MacMillan, D. W.C.  J. Am. Chem. Soc. 2006, 128, 84.
  2. Jain, P.; Antilla, J. C. J. Am. Chem. Soc., 2010, 132, 11884.
  3. Terada, M.; Serimachi, K. J. Am. Chem. Soc., 2007, 129, 292.
  4. Itoh, J.; Fuchibe, K.; Akiyama, T. Angew. Chem. Int. Ed. 2008, 47, 4016.
  5. He, Y.; Lin, M.; Li, Z.; Liang, X.; Li, G.; Antilla, J. C. Org. Lett., 2011, 13, 4490.