Rhodium Catalyzed Direct C-H Functionalization 陈殿峰
Outline : 1.Introduction 2.Oxidative coupling 3.Nucleophilic Addition 4.Other Reactions 5.Conclusion 2
1. Introduction 3
2. Oxidative Coupling DG = See: F. Glorius, J. A. Ellman, Sukbok Chang,T. Satoh, M. Miura Z.-J. Shi, X.-W. Li, T. Rovis, N. Cramer Oxidizing DG 4 Heck Type
Arylation Double C-H activation F.Glorious, Angew. Chem. Int. Ed. 2012, 51, 2247 M. Miura, Angew. Chem. Int. Ed. 2012, 51, Oxidative Coupling 5
Alkynylation Y= DG 2. Oxidative Coupling Alkynylation T. Satoh, M. Miura, Angew. Chem. Int. Ed. 2008, 47,
Alkynylation 2. Oxidative Coupling C. Zhu, Chem. Eur. J. 2011, 17, Alkynylation 7
F. Glorius, J. Am. Chem. Soc.,2012,134, Oxidative Coupling Halogenation Path a : nucleophilic addition Path b : high oxidation-state Rh(V) Alkynylation 8 B.-Q. Wang, J. Am. Chem. Soc., 2012, 134,16163
Oxidizing DG Background X.-L. Cui, Y.-J. Wu, J. Am. Chem. Soc., 2009, 131, Oxidative Coupling W.-Y. Yu, J. Am. Chem. Soc, 2010, 132,12862 J. F. Hartwig J. Am. Chem. Soc, 2010, 132,
N. Guimond, J. Am. Chem. Soc., 2010, 132, 6908 Oxidizing DG 2. Oxidative Coupling N. Guimond, J. Am. Chem. Soc, 2011, 133,
Z.-J. Shi, Angew. Chem. Int. Ed., 2012, 52, 3948 Oxidizing DG 2. Oxidative Coupling C-N Cleavage 11
2. Oxidative Coupling For Rh catalyzed oxidative coupling: 1). Rh(III) is generally efficient catalyst because its high oxidation- state facilitates β-elimination ; 2). Versatile DGs have been well established whereas DG-free coupling reactions are still rare; 3). The fact that more than stoichiometric metal-oxidants (Cu 2+, Ag + ) are generally needed callsfor eco-friendly pathways (air). 4). Harsh reaction conditions (high temprature, excess oxidant, strong base or acid) lead to poor functional group tolerence. 5). Limited examples involving sp 3 C-H activation are reported. 12
Direct Addition 3. Nucleophilic Addition 13
3. Nucleophilic Addition Direct Addition 14
R. G. Bergman, J. A. Ellman, J. Am. Chem. Soc. 2008, 130, Nucleophilic Addition Direct Addition R. G. Bergman, J. A. Ellman, J. Am. Chem. Soc. 2012, 134,
3. Nucleophilic Addition Direct Addition S.-M. Ma, J. Am. Chem. Soc. 2012, 134, 9597 C.-H. Cheng, Angew. Chem. Int. Ed., 2012, 51,
3. Nucleophilic Addition Direct Addition R. G. Bergman, J. A. Ellman, J. Am. Chem. Soc, , 1248 J. Am. Chem. Soc, , 1482 R. G. Bergman, J. A. Ellman, J. Am. Chem. Soc, , Others Acceptors Imine: Isocyanates:Aldehyde: Z.-J. Shi, Org. Lett, 2012, 14, 4498 Z.-J. Shi, Org. Lett, 2012, 14, 636 Org. Lett, 2012, 14,
Notes: 1.DG as acceptors; 2. Strained direct addition 3. Nucleophilic Addition Delayed Addition T. Satoh, M. Miura. Chem. Commun. 2009,
N. Cramer, Angew. Chem. Int. Ed, 2010, 49, 8181 N. Cramer, Angew. Chem. Int. Ed, 2011, 50, Nucleophilic Addition P.-J. Zhao, Chem. Eur. J. 2010, 16, 2619 Delayed Addition 19
C.-H. Cheng, Angew. Chem. Int. Ed, 2011, 50, 4169 F. Glorius, J. A m. Chem. Soc. 2011, 133, Nucleophilic Addition Delayed Addition 20
3. Nucleophilic Addition For nucleophilic C-Rh : 1). Rh(I)/Rh(III) are both efficient catalysts ; 2). More type of acceptors are needed to developed and three components reaction has not been reported; 3). Alkenes or other moities that could insert C-Rh bond may take the place of alkynes 4). Limited assymetric examples have been demonstrated, which indicates, in a way, the limitation of existing chiral ligands. 21
4. Other Reactions M. Murakami, J. A m. Chem. Soc. 2007, 129, Nucleophilic addition via C-C Cleavage M. Murakami, J. A m. Chem. Soc.2012, 134, ASAP. Oxidative Coupling via C-C Cleavage Z.-J. Shi, J. A m. Chem. Soc.2011, 133,
4. Other Reactions Carboacylation of Olefins G.-B. Dong, Angew. Chem. Int. Ed, 2012, 51, 7767 Ring Open of VCP Z.-X. Yu, J. A m. Chem. Soc.2011, 134, 398. Z.-X. Yu, Angew. Chem. Int. Ed, 2011, 50,
Z.-X. Yu, J. A m. Chem. Soc.2010, 132, Other Reactions 24
5. Conclusion: 25 1). Rh(I)/Rh(III) are versatile catalysts towards C-H bond activation; 2). Necessary DGs limite the substrates scope; 3). Direct sp 3 C-H functionalization remains challenging; 4). Mild reaction conditions are demanded for better functional group tolerence. 5). New chiral ligands or novel asymmetric catalytic circles would highlight Rh catalyzed C-H activation.