4 Dual Catalysis from Early and Late Metal Complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
5 Early–Late Heterobimetallic Complexes as New Anticancer Agents . . . . . . . . . . . . . . .. . . . . . 179
6 Conclusion . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 181
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
1 Introduction
Nowadays, homogeneous catalysis has become an indispensable tool for chemists by
the variety and selectivity of the reactions it allows [1]. However, the economic
development of our society in the context of sustainability pushes the chemists to find
novel catalysts more and more efficient able to create high value-added products from
abundant and environmentally benign substrates and reagents (or even from wastes)
at the minimum energy cost. A source of inspiration for chemists can be found in
enzymes which often surpass the most recent man-made catalysts both in activity and
selectivity using sustainable substrates and sources of energy [2]. While homogeneous catalysis predominantly involves only one catalytic center which is responsible
for the whole transformation of the substrate(s) into the product(s), catalytic sites in
enzymes are more sophisticated and are most of the time constituted by two or more
catalytic centers or functions which participate together in the reaction [3]. In consequence, it is rather clear that by taking example from nature or by following the
intuition that there is strength in numbers, one can hypothesize that the combination
of catalysts or of catalytic functions within the same entity constitutes a promising
strategy for improving or discovering chemical reactions.
Before focusing on the main topic of this chapter that concerns “early–late heterobimetallic complexes in catalysis,” we will present, in a first part, representative examples of cooperative catalysis besides “early–late” heterobimetallic catalysts, which
provide some information about which type of catalysts or catalytic functions have
been combined to date and illustrate the different cooperative effects that have been
observed. The second part is concerned with “early–late” heterobimetallic catalysis and
encompasses the period from about 1988 to June 2015. It follows two reviews by Kalck
[4] and Thomas [5] which cover the periods 1988–1997 and 2000–2011, respectively,
and classified the data according to the catalytic reaction involved. We have chosen
to look at this topic from another perspective and categorized the data by group of the
late transition metal which often governs the catalytic reaction, by element and finally
by the catalytic reaction involved. The reader will thus notice that some bimetallic
combinations are much less represented or nonexistent which raises the crucial question of catalyst compatibility. Since the terms “early” and “late” are not strictly defined
in the literature, we will first focus on combinations from groups 4 and 5 for early
transition metals and groups 8, 9, and 10 for late transition metals. Consequently, the
second part of this chapter begins with catalytic reactions promoted by (group 8/groups
4–5) bimetallic complexes followed by (group 9/groups 4–5) and (group 10/groups
4–5) combinations. The third part of this chapter is devoted to dual catalysis from
early and late metal complexes and may constitute a source of inspiration for further
design of new early–late heterobimetallic catalysts. The last part of this chapter is
140
E. Bodio et al.
5 Early–Late Heterobimetallic Complexes as New Anticancer Agents . . . . . . . . . . . . . . .. . . . . . 179
6 Conclusion . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 181
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
1 Introduction
Nowadays, homogeneous catalysis has become an indispensable tool for chemists by
the variety and selectivity of the reactions it allows [1]. However, the economic
development of our society in the context of sustainability pushes the chemists to find
novel catalysts more and more efficient able to create high value-added products from
abundant and environmentally benign substrates and reagents (or even from wastes)
at the minimum energy cost. A source of inspiration for chemists can be found in
enzymes which often surpass the most recent man-made catalysts both in activity and
selectivity using sustainable substrates and sources of energy [2]. While homogeneous catalysis predominantly involves only one catalytic center which is responsible
for the whole transformation of the substrate(s) into the product(s), catalytic sites in
enzymes are more sophisticated and are most of the time constituted by two or more
catalytic centers or functions which participate together in the reaction [3]. In consequence, it is rather clear that by taking example from nature or by following the
intuition that there is strength in numbers, one can hypothesize that the combination
of catalysts or of catalytic functions within the same entity constitutes a promising
strategy for improving or discovering chemical reactions.
Before focusing on the main topic of this chapter that concerns “early–late heterobimetallic complexes in catalysis,” we will present, in a first part, representative examples of cooperative catalysis besides “early–late” heterobimetallic catalysts, which
provide some information about which type of catalysts or catalytic functions have
been combined to date and illustrate the different cooperative effects that have been
observed. The second part is concerned with “early–late” heterobimetallic catalysis and
encompasses the period from about 1988 to June 2015. It follows two reviews by Kalck
[4] and Thomas [5] which cover the periods 1988–1997 and 2000–2011, respectively,
and classified the data according to the catalytic reaction involved. We have chosen
to look at this topic from another perspective and categorized the data by group of the
late transition metal which often governs the catalytic reaction, by element and finally
by the catalytic reaction involved. The reader will thus notice that some bimetallic
combinations are much less represented or nonexistent which raises the crucial question of catalyst compatibility. Since the terms “early” and “late” are not strictly defined
in the literature, we will first focus on combinations from groups 4 and 5 for early
transition metals and groups 8, 9, and 10 for late transition metals. Consequently, the
second part of this chapter begins with catalytic reactions promoted by (group 8/groups
4–5) bimetallic complexes followed by (group 9/groups 4–5) and (group 10/groups
4–5) combinations. The third part of this chapter is devoted to dual catalysis from
early and late metal complexes and may constitute a source of inspiration for further
design of new early–late heterobimetallic catalysts. The last part of this chapter is
140
E. Bodio et al.