Recent advances in the use of unsymmetrical palladium pincer complexes

Current Organic Chemistry

Volumn 13, Issue 9, 2009, Pages 878-895

  Moreno, I ^a   SanMartin, Raul ^a   Ines B ^a   Herrero, M T ^a   Dominguez E ^a  

^a UNIVERSITY OF THE BASQUE COUNTRY UPV EHU   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

CHEMICAL BONDS; PALLADIUM COMPOUNDS; STEEL BEAMS AND GIRDERS; SYNTHESIS (CHEMICAL);

CATALYSE; DONOR GROUPS; HIGHER EFFICIENCY; ORGANIC REACTION; PALLADACYCLES; PALLADIUM PINCER-COMPLEXES; PALLADIUM-CATALYZED REACTIONS; PROPERTY; SYNTHETIC APPLICATION; TRIDENTATE LIGANDS;

CATALYST ACTIVITY;

EID: 70349962948     PISSN: 13852728     EISSN: None     Source Type: Journal    
DOI: 10.2174/138527209788452144     Document Type: Review

References (119)

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70. More details about the synthesis of the ligand in: Motoyama, Y.; Shimozono, K.; Nishiyama, H. Novel (oxazolinyl)phenyl phosphinite pincer ligand: development of the first nonsymmetrical, PCN type chiral palladium and platinum complexes. Inorg. Chem. Acta, 2006, 359, 1725-1730.
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73. The oxidative addition procedure applied for the synthesis of symmetric SCS-pincer derivatives is reported in: Kruithof, C. A.; Dijkstra, H. P.; Lutz, M.; Spek, A. L.; Gebbink, R. J. M. K.; van Koten, G. X-ray and NMR study of the structural features of SCS-pincer metal complexes of the group 10 Triad. Organometallics, 2008, 27, 4928-4937.
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77. (d) Consorti, C. S.; Ebeling, G.; Flores, F. R.; Rominger, F. On the use of non-symmetrical mixed PCN and SCN pincer palladacycles as catalyst precursors for the Heck reaction. Adv. Synth. Catal., 2004, 346, 617-624.
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83. The use of a series of SCS complexes in the Heck coupling in: Bergbreiter, D. E.; Osburn, P. L.; Liu, Y.-S. Tridentate SCS Palladium(II) complexes: new, highly stable, recyclable catalysts for the Heck reaction. J. Am. Chem. Soc., 1999, 121, 9531-9538.
84. Examples of the application of symmetric pincer palladacyles in Suzuki-Miyaura cross-coupling are reported in: Luo, Q.; Eibauer, S.; Reiser, O. Novel bis(oxazole) pincer ligands for catalysis: application in Suzuki-Miyaura cross coupling reactions under aerobic conditions. J. Mol. Catal., 2007, 268, 65-69.
85. (b) Liau, C.-Y.; Chan, K.-T.; Zeng, J.-Y.; Hu, C.-H.; Tu, C.-Y.; Lee, H. M. Nonchelate and chelate complexes of Palladium(II) with N-heterocyclic carbene ligands of amido functionality. Organometallics, 2007, 26, 1692-1702.
86. (c) Bianchini, C.; Lenoble, G.; Oberhauser, W.; Parisel, S.; Zanobini, F. Synthesis, characterization, and reactivity of neutral and cationic Pd-C,N,N pincer complexes. Eur. J. Inorg. Chem., 2005, 4794-4800.
87. (d) Churruca, F.; SanMartin, R.; Tellitu, I.; Dominguez, E. N-Heterocyclic NCN-pincer palladium complexes: a source for general, highly efficient catalysts in Heck, Suzuki, and Sonogashira coupling reactions. Synlett, 2005, 3116-3120.
88. (e) Bedford, R. B.; Draper, S. M.; Scully, P. N.; Welch, S. L. Palladium bis(phosphinite) PCP-pincer complexes and their application as catalysts in the Suzuki reaction. New. J. Chem., 2000, 24, 745-747.
89. (f) Bolliger, J. L.; Blacque, O.; French, C. M. Short, facile, and high-yielding synthesis of extremely efficient pincer-type Suzuki catalysts bearing aminophosphine substituents. Angew. Chem. Int. Ed., 2007, 46, 6514-6517.
90. (g) Kimura, T.; Uozumi, Y. PCP pincer palladium complexes and their catalytic properties: synthesis via the electrophilic ligand introduction route. Organometallics, 2006, 25, 4883-4887.
91. (h) Benito-Garagorri, D.; Cocokic, V.; Kirchner, K. A modular approach to achiral and chiral Nickel(II), Palladium(II), and Platinum(II) PCP pincer complexes based on diaminobenzenes. Organometallics, 2006, 25, 3817-3823.
92. 5)]}OTf. Eur. J. Inorg. Chem., 2008, 572-576.
93. Rosa, G. R.; Rosa, C. H.; Rominger, F. R.; Dupont, J.; Monteiro, A. L. A mixed NCP pincer palladacycle as catalyst precursor for the coupling of aryl halides with aryl boronic acids. Inorg. Chim. Acta, 2006, 359, 1947-1954.
94. The employment of this pincer as catalyst precursor provided better results than the classical methodology (94-99% vs 48%): DaSilveira Neto, B. A.; Lopes, A. S. A.; Ebeling, G.; Gonsalves, R. S.; Costa, V. E. U.; Quina, F. H.; Dupont, J. Photophysical and electrochemical properties of II-extended molecular 2,1,3-benzothiadiazoles. Tetrahedron, 2005, 61, 10975-10982.
95. Mancilha, F. S.; DaSilveira Neto, B. A.; Lopes, A. S.; Moreira, P. F.; Quina, F. H.; Gonsalves, R. S.; Dupont, J. Are molecular 5,8-II-extended quinoxaline derivatives good chromophores for photoluminescence applications? Eur. J. Org. Chem., 2006, 4924-4933.
96. For more details about the catalytic studies see reference 27.
97. For a minireview focused on cross-couplings with non activated alkyl halides see: (a) Frisch, A. C.; Beller, M. Catalysts for cross-coupling reactions with non-activated alkyl halides. Angew. Chem. Int. Ed., 2005, 44, 674-688.
98. See also: (b) Doucet, H. Suzuki-Miyaura cross-coupling reactions of alkylboronic acid derivatives or alkyitrifluoroborates with aryl, alkenyl or alkyl halides and triflates. Eur. J. Org. Chem., 2008, 2013-2030.
99. Inés, B.; Moreno, I.; SanMartin, R.; Domínguez, E. A nonsymmetric pincer-catalyzed Suzuki-Miyaura arylation of benzyl halides and other nonactivated unusual coupling partners. J. Org. Chem., 2008, 73, 8448-8451.
100. Suzuki-Miyaura coupling of α-haloenones is described in: (a) Felpin, F.-X. Practical and efficient Suzuki-Miyaura cross-coupling of 2-iodocycloenones with arylboronic acids catalyzed by recyclable Pd(0)/ C. J. Org. Chem., 2005, 70, 8575-8578.
101. (b) Banks, J. C.; Van Mele, D.; Frost, C. G. The α-arylation of σ-bromo- and α-chloroenones using palladium-catalyzed cross-coupling. Tetrahedron Lett., 2006, 47, 2863-2866.
102. (c) Burns, M. J.; Fairlamb, J. S.; Kapdi, A. R.; Sehnal, P.; Taylor, R. J. K. Simple Palladium(II) precatalyst for Suzuki-Miyaura couplings: efficient reactions of benzylic, aryl, heteroaryl, and vinyl coupling partners. Org. Lett., 2007, 9, 5397-5400.
103. (d) Dawood, K. M. Microwave-assisted Suzuki-Miyaura and Heck-Mizoroki cross-coupling reactions of aryl chlorides and bromides in water using stable benzothiazole-based palladium(II) precatalysts. Tetrahedron, 2007, 63, 9642-9651.
104. Some examples of the Suzuki-Miyaura reaction employing alkylboronic acids are provided in: (a) Kondolff, I.; Doucet, H.; Santelli, M. Tetraphosphine/palladium-catalyzed Suzuki cross-coupling reactions of aryl halides with alkylboronic acids. Tetrahedron, 2004, 60, 3813-3818.
105. (b) Molander, G. A.; Yun, C.-S. Cross-coupling reactions of primary alkylboronic acids with aryl triflates and aryl halides. Tetrahedron, 2002, 58, 1465-1470.
106. (c) Andrus, M. B.; Song, M. B. Palladium-imidazolium carbene catalyzed aryl, vinyl, and alkyl Suzuki-Miyaura cross coupling. Org. Lett., 2001, 3, 3761-3764. See also reference 50b.
107. The use of benzyl halides in the Suzuki-Miyaura coupling is described in: (a) Chang, C.-P.; Huang, Y. L.; Hong, F.-E. Biphasic Suzuki coupling reactions of aryl or benzyl bromides employing cobalt-containing phosphine ligand coordinated palladium complex. Tetrahedron, 2005, 61, 3835-3839.
108. (b) Bandgar, B. P.; Bettigeri, S. V.; Phopase, J. Palladium catalyzed ligand-free Suzuki cross-coupling reactions of benzylic halides with aryl boronic acids under mild conditions. Tetrahedron Lett., 2004, 45, 6959-6962.
109. (c) Langle, S.; Abarbi, M.; Duchene A. Selective double Suzuki cross-coupling reactions. Synthesis of unsymmetrical diaryl (or heteroaryl) methanes. Tetrahedron Lett., 2003, 44, 9255-9258.
110. (d) Miyaura, N.; Yano, T.; Suzuki, A. The palladium-catalyzed cross-coupling reaction of 1-alkenylboranes with allylic or benzylic bromides. Convenient syntheses of 1,4-alkadienes and allylbenzenes from alkynes via hydroboration. Tetrahedron Lett., 1980, 21, 2865-2868.
111. (e) Chahen, L.; Doucet, H.; Santelli, M. Suzuki cross-coupling reaction of benzylic halides with arylboronic acids in the presence of a tetraphosphine/palladium catalyst. Synlett, 2003, 1668-1672.
112. (f) Botella, L.; Nájera, C. Cross-coupling reactions with boronic acids in water catalysed by oxime-derived palladacycles. J. Organomet. Chem., 2002, 663, 46-57.
113. (g) Botella, L.; Nájera, C. A convenient oxime-carbapalladacycle-catalyzed Suzuki cross-coupling of aryl chlorides in water. Angew. Chem. Int. Ed., 2002, 41, 179-181.
114. See also reference 50b.
115. For more experimental details see reference 31.
116. 3) in Sonogashira reactions catalyzed by a symmetric NCN-type pincer palladacycle: Churruca, F.; SanMartin, R.; Tellitu, I.; Dominguez, E. N-Heterocyclic NCN-pincer palladium complexes: A source for general, highly efficient catalysts in Heck, Suzuki, and Sonogashira coupling reactions. Synlett, 2005, 3116-3120.
117. For more details about the experimental considerations see supporting material of the reference 30.
118. For more details about the synthesis or the catalytic activity of these unsymmetric palladacycles see: Wang, Z.; Eberhard, M. R.; Jensen, C. M.; Matsukawa, S.; Yamamoto, Y. A structure-activity relationship for pincer palladium(II) complexes - influence of ring-size of metallacycles on the activity in allylic alkylation. J. Organomet. Chem., 2003, 681, 189-195.
119. Better yields and enantiomeric excesses were obtained with gold pincer-type derivatives.