Benjamin List talks with
ScienceWatch.com and answers a few questions about
this month's Fast Moving Front in the field of
Article: Asymmetric enamine
Authors: Mukherjee, S;Yang, JW;Hoffmann,
Journal: CHEM REV, 107 (12): 5471-5569 DEC 2007
Addresses: Max Planck Inst Kohlenforsch, D-45470 Mulheim An
Der Ruhr, Germany.
Max Planck Inst Kohlenforsch, D-45470 Mulheim An Der Ruhr,
Why do you think your paper is highly
Our paper is a review covering "enamine catalysis" as an area of catalysis
that has grown considerably during the last nine years. While appreciated
as an enzymatic reaction mechanism, chemists hardly made use of this
powerful concept over the last century, especially not in asymmetric
catalysis. This has changed significantly and, since 2000, there have been
literally hundreds of papers on the subject, with new ones coming up on a
Does it describe a new discovery, methodology, or
synthesis of knowledge?
Enamine catalysis is new as a general methodology. In enamine catalysis,
amines are used as catalysts with a well-defined mode of action, reacting
carbonyl compounds with electrophiles. The generalization and
conceptualization of enamine catalysis has inspired the design of many new
reactions and powerful catalysts.
Would you summarize the significance of your paper
in layman’s terms?
"We describe the results of hundreds
of groups around the
Perhaps its key significance lies in the possibility of "making life-saving
drugs with edible catalysts."
How did you become involved in this research and
were any particular problems encountered along the way?
We describe the results reported by hundreds of groups around the world.
Our own studies date back to the very beginning of the field in 2000.
Inspiration came from reactions developed by industrial chemists in the
late 1960s as well as from work done with catalytic antibodies. My idea has
been to catalyze the intermolecular aldol reaction, at the time a huge
challenge to asymmetric catalysis, with the amino acid proline.
Indeed, this catalyst turned out to be state-of-the-art, comparable only to
a complex lanthanum catalyst that was developed by Masakatsu Shibasaki's
group at the University of Tokyo. Shortly after our initial observation, we
have discovered other reactions that can be catalyzed using the same
activation principle, which we have termed "enamine catalysis."
Regarding problems encountered along the way, two big challenges right from
the beginning were (a) the skeptical advice by colleagues that organic
catalysts should be generally less active and selective compared to
transition metal catalysts and enzymes and (b) subsequent competition from
the same people after proving them wrong.
Where do you see your research leading in the
It looks like there is a deeper understanding of enamine catalysis now and
of the things you can accomplish with it. The concept of enamine catalysis
has led to major discoveries of which chemists had not even dreamed until
now. However, there are remaining challenges, certain other "dream
reactions" we would still like to discover.
Do you foresee any social or political implications
for your research?
It would certainly be nice if our concepts would help in improving life on
earth by enabling the environmentally friendly and safe synthesis of drugs
for human health.
Prof. Dr. Benjamin List
Max-Planck-Institut für Kohlenforschung
Mülheim an der Ruhr, Germany
The Research Group of Benjamin List: Web