singular structural features. The well-defined structure and tunability of pincer
compounds often offer improved and, in some cases, unique catalytic properties
when compared to conventional systems. However, after many years of very fruitful
research in this area, further progress toward new, efficient catalysis should not
remain limited to routine structure-reactivity screening – it requires the development
of new reaction schemes and reactivity patterns.
Designing catalysts possessing noninnocent ligands is a very new development in
organometallic chemistry. This trend also appears as a fresh direction in the chemistry of pincer complexes, resulting in many publications concerning ligand-metal
cooperating pincer catalysts operating via diverse mechanisms. This chapter focused
on recent progress in the chemistry and catalytic applications of pincer compounds
incorporating the secondary coordination sphere or an appended functionality that
can interact with the catalytic center or can modulate its reactivity via secondary
substrate-catalyst interactions. We overviewed the intriguing reactivity of such
multifunctional catalytic systems while trying to stress the need for new platforms
that combine the concepts of modular and stable pincer ligands and outer-sphere
reactivity, thus providing excellent opportunities for creating challenging targetoriented catalysis.
Acknowledgments This research was supported by GIF (German-Israeli Foundation for research
and development) Grant N I-1508-302.5/2019. This work was supported by the RUDN University
Program “5-100.” We are grateful for all stimulating discussion with many colleagues and friends
and in particular for all work and insights provided by current and past group members.
References
1. van Koten G (2013) Pincer ligands as powerful tools for catalysis in organic synthesis. J
Organomet Chem 730:156–164. https://doi.org/10.1016/j.jorganchem.2012.12.035
2. Deng Q-H, Melen RL, Gade LH (2014) Anionic chiral tridentate N-donor pincer ligands in
asymmetric catalysis. Acc Chem Res 47(10):3162–3173. https://doi.org/10.1021/ar5002457
3. Asay M, Morales-Morales D (2015) Non-symmetric pincer ligands: complexes and applications in catalysis. Dalton Trans 44(40):17432–17447. https://doi.org/10.1039/C5DT02295A
4. Andrew RE, Gonzalez-Sebastian L, Chaplin AB (2016) NHC-based pincer ligands: carbenes
with a bite. Dalton Trans 45(4):1299–1305. https://doi.org/10.1039/C5DT04429D
5. Melen RL, Gade LH (2016) New chemistry with anionic NNN pincer ligands. Top Organomet
Chem 54:179–208. https://doi.org/10.1007/3418_2015_114
6. Lawrence MAW, Green K-A, Nelson PN, Lorraine SC (2018) Review: pincer ligands-tunable,
versatile and applicable. Polyhedron 143:11–27. https://doi.org/10.1016/j.poly.2017.08.017
7. Maser L, Vondung L, Langer R (2018) The ABC in pincer chemistry - from amine- to
borylene- and carbon-based pincer-ligands. Polyhedron 143:28–42. https://doi.org/10.1016/j.
poly.2017.09.009
8. Alig L, Fritz M, Schneider S (2019) First-row transition metal (De)hydrogenation catalysis
based on functional pincer ligands. Chem Rev 119(4):2681–2751. https://doi.org/10.1021/acs.
chemrev.8b00555
9. Albrecht M, van Koten G (2001) Platinum group organometallics based on "pincer" complexes: sensors, switches, and catalysts. Angew Chem Int Ed 40(20):3750–3781. https://doi.
org/10.1002/1521-3773(20011015)40:20<3750::AID-ANIE3750>3.0.CO;2-6
Cooperative Reactivity by Pincer-Type Complexes Possessing Secondary. . .
127
compounds often offer improved and, in some cases, unique catalytic properties
when compared to conventional systems. However, after many years of very fruitful
research in this area, further progress toward new, efficient catalysis should not
remain limited to routine structure-reactivity screening – it requires the development
of new reaction schemes and reactivity patterns.
Designing catalysts possessing noninnocent ligands is a very new development in
organometallic chemistry. This trend also appears as a fresh direction in the chemistry of pincer complexes, resulting in many publications concerning ligand-metal
cooperating pincer catalysts operating via diverse mechanisms. This chapter focused
on recent progress in the chemistry and catalytic applications of pincer compounds
incorporating the secondary coordination sphere or an appended functionality that
can interact with the catalytic center or can modulate its reactivity via secondary
substrate-catalyst interactions. We overviewed the intriguing reactivity of such
multifunctional catalytic systems while trying to stress the need for new platforms
that combine the concepts of modular and stable pincer ligands and outer-sphere
reactivity, thus providing excellent opportunities for creating challenging targetoriented catalysis.
Acknowledgments This research was supported by GIF (German-Israeli Foundation for research
and development) Grant N I-1508-302.5/2019. This work was supported by the RUDN University
Program “5-100.” We are grateful for all stimulating discussion with many colleagues and friends
and in particular for all work and insights provided by current and past group members.
References
1. van Koten G (2013) Pincer ligands as powerful tools for catalysis in organic synthesis. J
Organomet Chem 730:156–164. https://doi.org/10.1016/j.jorganchem.2012.12.035
2. Deng Q-H, Melen RL, Gade LH (2014) Anionic chiral tridentate N-donor pincer ligands in
asymmetric catalysis. Acc Chem Res 47(10):3162–3173. https://doi.org/10.1021/ar5002457
3. Asay M, Morales-Morales D (2015) Non-symmetric pincer ligands: complexes and applications in catalysis. Dalton Trans 44(40):17432–17447. https://doi.org/10.1039/C5DT02295A
4. Andrew RE, Gonzalez-Sebastian L, Chaplin AB (2016) NHC-based pincer ligands: carbenes
with a bite. Dalton Trans 45(4):1299–1305. https://doi.org/10.1039/C5DT04429D
5. Melen RL, Gade LH (2016) New chemistry with anionic NNN pincer ligands. Top Organomet
Chem 54:179–208. https://doi.org/10.1007/3418_2015_114
6. Lawrence MAW, Green K-A, Nelson PN, Lorraine SC (2018) Review: pincer ligands-tunable,
versatile and applicable. Polyhedron 143:11–27. https://doi.org/10.1016/j.poly.2017.08.017
7. Maser L, Vondung L, Langer R (2018) The ABC in pincer chemistry - from amine- to
borylene- and carbon-based pincer-ligands. Polyhedron 143:28–42. https://doi.org/10.1016/j.
poly.2017.09.009
8. Alig L, Fritz M, Schneider S (2019) First-row transition metal (De)hydrogenation catalysis
based on functional pincer ligands. Chem Rev 119(4):2681–2751. https://doi.org/10.1021/acs.
chemrev.8b00555
9. Albrecht M, van Koten G (2001) Platinum group organometallics based on "pincer" complexes: sensors, switches, and catalysts. Angew Chem Int Ed 40(20):3750–3781. https://doi.
org/10.1002/1521-3773(20011015)40:20<3750::AID-ANIE3750>3.0.CO;2-6
Cooperative Reactivity by Pincer-Type Complexes Possessing Secondary. . .
127