Synthesis and Characterization of New Chiral Monoanionic [ON] Ancillary Phenolate Ligands

Pascal Binda, Leslie Glover

Department of Chemistry and Forensic Science, Savannah State University, Savannah, GA, USA.
Science Division, Southern Wesleyan University, Central, SC, USA.

DOI: 10.4236/ijoc.2014.43020                

Abstract

Three new chiral monoanionic [ON] ancillary phenolate ligands with varying pendant arms have been synthesized in moderate to high yields (50% - 85%) via Mannich-type condensation reaction of chiral substituted phenol, formaldehyde and (+)-bis-[(R)-1-phenylethyl]amine. These new organic compounds were fully characterized via nuclear magnetic resonance spectroscopy (¹H and ¹³C) and elemental analysis. The newly synthesized ligands are suitable candidates for metal-catalyzed ring-opening of lactones and asymmetric catalysis.

Keywords

Phenolate Ligands, Mannich Condensation Reaction, Ring-Opening Polymerization of Lactones

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Walsh, P.J. and Kozlowski, M.C. (2008) Fundamentals in Asymmetric Catalysis. USB, Sausalito. http://dx.doi.org/10.1007/978-3-642-58571-5
[2]	Jacobsen, E.N., Pfaltz, A. and Yamamoto, H. (1999) Comprehensive Asymmetric Catalysis. Springer, Heidelberg.
[3]	Martin, R., Buchwald, S.L. (2008) Palladium-Catalyzed Suzuki-Miyaura Cross-Coupling Reactions Employing Dialkylbiaryl Phosphine Ligands. Accounts of Chemical Research, 41, 1461-1473. http://dx.doi.org/10.1021/ar800036s
[4]	Heitbaum, M., Glorius, F. and Escher, I. (2006) Asymmetric Heterogeneous Catalysis. Angewandte Chemie International Edition, 45, 4732-4762. http://dx.doi.org/10.1002/anie.200504212
[5]	Miura, M. (2004) Rational Ligand Design in Constructing Efficient Catalyst Systems for Suzuki-Miyaura Coupling. Angewandte Chemie International Edition, 43, 2201-2203. http://dx.doi.org/10.1002/anie.200301753
[6]	Katz, B.A., Cass, R.T., Liu, B., Arze, R. and Collins, N. (1995) Topochemical Catalysis Achieved by Structure-Based Ligand Design. The Journal of Biological Chemistry, 270, 31210-31218.
[7]	Falciola, C.A. and Alexakis, A. (2008) Copper-Catalyzed Asymmetric Allylic Alkylation. European Journal of Organic Chemistry, 3765-3780. http://dx.doi.org/10.1002/ejoc.200800025
[8]	Hoveyda, A.H., Hird, A.W. and Kacprzynski, M.A. (2004) Small Peptides as Ligands for Catalytic Asymmetric Alkylations of Olefins. Chemical Communications, 1779-1883. http://dx.doi.org/10.1039/b401123f
[9]	Lu, Y., Johnstone, T.C. and Arndtsen, B.A. (2009) Hydrogen-Bonding Asymmetric Metal Catalysis with α-Amino Acids: A Simple and Tunable Approach to High Enantioinduction. Journal of the American Chemical Society, 131, 11284-11285. http://dx.doi.org/10.1021/ja904185b
[10]	Shi, B.-F., Maugel, N., Zhang, Y.-H. and Yu, J.-Q. (2008) PdII-Catalyzed Enantioselective Activation of C(sp2)-H and C(sp3)-H Bonds Using Monoprotected Amino Acids as Chiral Ligands. Angewandte Chemie International Edition, 47, 4882-4886. http://dx.doi.org/10.1002/anie.200801030
[11]	Blaser, H.-U., Pugin, B., Spindler, F. and Thommen, M. (2007) From a Chiral Switch to a Ligand Portfolio for Asymmetric Catalysis. Accounts of Chemical Research, 40, 1240-1250. http://dx.doi.org/10.1021/ar7001057
[12]	Cesar, V., Bellemin-Laponnaz, S., Wadepohl, H. and Gade, L.H. (2005) Designing the “Search Pathway” in the Development of a New Class of Highly Efficient Stereoselective Hydrosilylation Catalysts. Chemistry—A European Journal, 11, 2862-2873. http://dx.doi.org/10.1002/chem.200500132
[13]	Delbridge, E.E., Dugah, D.T., Nelson, C.R., Skelton, B.W. and White, A.H. (2007) Synthesis, Structure and Oxidation of New Ytterbium(II) Bis(phenolate) Compounds and Their Catalytic Activity Towards Epsilon-Caprolactone. Dalton Transactions, No. 1, 143-153.
[14]	Binda, P.I. and Delbridge, E.E. (2007) Synthesis and Characterisation of Lanthanide Phenolate Compounds and Their Catalytic Activity towards Ring-Opening Polymerisation of Cyclic Esters. Dalton Transactions, 41, 4685-4692. http://dx.doi.org/10.1039/b710070a
[15]	Kerton, F.M., Whitwood, A.C. and Willans, C.E. (2004) A High-Throughput Approach to Lanthanide Complexes and Their Rapid Screening in the Ring Opening Polymerisation of Caprolactone. Dalton Transactions, No. 15, 2237-2244. http://dx.doi.org/10.1039/b406841f
[16]	Binda, P.I., Delbridge, E.E., Abrahamson, H.B. and Skelton, B.W. (2009) Coordination of Substitutionally Inert Phenolate Ligands to Lanthanide(II) and (III) Compounds—Catalysts for Ring-Opening Polymerization of Cyclic Esters. Dalton Transactions, No. 15, 2777-2787. http://dx.doi.org/10.1039/b821770j
[17]	Dugah, D.T., Skelton, B.W. and Delbridge, E.E. (2009) Synthesis and Characterization of New Divalent Lanthanide Complexes Supported by Amine Bis(Phenolate) Ligands and Their Applications in the Ring Opening Polymerization of Cyclic Esters Dalton Transactions, 1436-1445. http://dx.doi.org/10.1039/b816916k
[18]	Xu, X., Ma, M., Yao, Y., Zhang, Y. and Shen, Q. (2005) Synthesis, Characterisation of Carbon-Bridged (Diphenolato) Lanthanide Complexes and Their Catalytic Activity for Diels-Alder Reactions. European Journal of Inorganic Chemistry, 2005, 676-684. http://dx.doi.org/10.1002/ejic.200400519
[19]	Lendlein, A., Schmidt, A.M., Schroeter, M. and Langer, R. (2005) Shape-Memory Polymer Networks from Oligo (∈-Caprolactone) Dimethacrylates. Journal of Polymer Science Part A: Polymer Chemistry, 43, 1369-1381. http://dx.doi.org/10.1002/pola.20598
[20]	Amgoune, A., Thomas, C.M., Roisnel, T. and Carpentier, J.F. (2005) Ring-Opening Polymerization of Lactide with Group 3 Metal Complexes Supported by Dianionic Alkoxy-Amino-Bisphenolate Ligands: Combining High Activity, Productivity and Selectivity. Chemistry—A European Journal, 12, 169-179. http://dx.doi.org/10.1002/chem.200500856
[21]	Guo, H., Zhou, H., Yao, Y., Zhang, Y. and Shen, Q. (2007) Synthesis and Structural Characterization of Novel Mixed-Valent Samarium and Divalent Ytterbium and Europium Complexes Supported by Amine Bis(phenolate) Ligand. Dalton Transactions, No. 32, 3555-3561. http://dx.doi.org/10.1039/b705353c
[22]	Zats, G.M., Arora, H., Lavi, R., Yufit, D. and Benisvy, L. (2011) Phenolate and Phenoxyl Radical Complexes of Cu(II) and Co(III), Bearing a New Redox Active N,O-Phenol-Pyrazole Ligand. Dalton Transactions, 40, 10889-10896. http://dx.doi.org/10.1039/c1dt10615e
[23]	Radano, C.P., Baker, G.L. and Smith, M.R. (2000) Stereoselective Polymerization of a Racemic Monomer with a Racemic Catalyst: Direct Preparation of the Polylactic Acid Stereocomplex from Racemic Lactide. Journal of the American Chemical Society, 122, 1552-1553. http://dx.doi.org/10.1021/ja9930519
[24]	Darensbourg, D.J., Choi, W., Karroonnirum, O. and Bhuvanesh, N. (2008) Ring-Opening Polymerization of Cyclic Monomers by Complexes Derived from Biocompatible Metals. Production of Poly(lactide), Poly(trimethylene carbonate) and Their Copolymers. Macromolecules, 41, 3493-3502. http://dx.doi.org/10.1021/ma800078t
[25]	Ovitt, T.M. and Coates, G.W. (2002) Stereochemistry of Lactide Polymerization with Chiral Catalysts: New Opportunities for Stereocontrol Using Polymer Exchange Mechanisms. Journal of the American Chemical Society, 124, 1316-1326. http://dx.doi.org/10.1021/ja012052+
[26]	Kasperczyk, J.E. (1995) Microstructure Analysis of Poly(lactic acid) Obtained by Lithium Tert-Butoxide as Initiator. Macromolecules, 28, 3937-3939. http://dx.doi.org/10.1021/ma00115a028
[27]	Radano, C.P., Baker, G.L. and Smith III, M.R. (2000) Stereoselective Polymerization of a Racemic Monomer with a Racemic Catalyst: Direct Preparation of the Polylactic Acid Stereocomplex from Racemic Lactide. Journal of the American Chemical Society, 12, 1552-1553. http://dx.doi.org/10.1021/ja9930519
[28]	Thakur, K.A.M., Kean, R.T., Zell, M.T., Padden, B.E. and Munson, E.J. (1998) An Alternative Interpretation of the HETCOR NMR Spectra of Poly(lactide). Chemical Communications, No. 17, 1913-1914. http://dx.doi.org/10.1039/a708911b
[29]	Thakur, K.A.M., Kean, R.T., Hall, E.S., Kolstad, J.J. and Lindgren, T.A. (1997) High-Resolution 13C and 1H Solution NMR Study of Poly(lactide). Macromolecules, 30, 2422-2428. http://dx.doi.org/10.1021/ma9615967
[30]	Zell, M.T., Padden, B.E., Paterick, A.J., Thakur, K.A.M., Kean, R.T., Hillmyer, M.A. and Munson, E.J. (2002) Unambiguous Determination of the 13C and 1H NMR Stereosequence Assignments of Polylactide Using High-Resolution Solution NMR Spectroscopy. Macromolecules, 35, 7700-7707. http://dx.doi.org/10.1021/ma0204148
[31]	Ovitt, T.M. and Coates, G.W. (2000) Stereoselective Ring-Opening Polymerization of Rac-Lactide with a Single-Site, Racemic Aluminum Alkoxide Catalyst: Synthesis of Stereoblock Poly(lactic acid), Polymer Chemistry, 38, 4686-4692. http://dx.doi.org/10.1002/1099-0518(200012)38:1+<4686::AID-POLA80>3.0.CO;2-0
[32]	Cheng, M., Attygalle, A.B., Lobkovsky, E.B. and Coates, G.W. (1999) Single-Site Catalysts for Ring-Opening Polymerization: Synthesis of Heterotactic Poly(lactic acid) from Rac-Lactide. Journal of the American Chemical Society, 121, 11583-11584. http://dx.doi.org/10.1021/ja992678o
[33]	Ovitt, T.M and Coates, G.W. (1999) Stereoselective Ring-Opening Polymerization of meso-Lactide: Synthesis of Syndiotactic Poly(lactic acid). Journal of the American Chemical Society, 121, 4072-4073. http://dx.doi.org/10.1021/ja990088k
[34]	Chisholm, M.H., Iyer, S.S., McCollum, D.G., Pagel, M. and Werner-Zwanziger, U. (1999) Microstructure of Poly(lactide). Phase-Sensitive HETCOR Spectra of Poly(meso-lactide), Poly(rac-lactide) and Atactic Poly(lactide). Macromolecules, 32, 963-973. http://dx.doi.org/10.1021/ma9806864
[35]	Chisholm, M.H., Gallucci, J.C. and Phomphrai, K. (2005) Comparative Study of the Coordination Chemistry and Lactide Polymerization of Alkoxide and Amide Complexes of Zinc and Magnesium with a β-Diiminato Ligand Bearing Ether Substituents. Inorganic Chemistry, 44, 8004-8010. http://dx.doi.org/10.1021/ic048363d
[36]	Zhong, Z., Dijkstra, P.J. and Feijen, J. (2003) Controlled and Stereoselective Polymerization of Lactide: Kinetics, Selectivity, and Microstructures. Journal of the American Chemical Society, 125, 11291-11298. http://dx.doi.org/10.1021/ja0347585
[37]	Cai, C.-X., Amgoune, A., Lehmann, C.W. and Carpentier, J.-F. (2004) Stereoselective Ring-Opening Polymerization of Racemic Lactide Using Alkoxy-Amino-Bis(phenolate) Group 3 Metal Complexes. Chemical Communications, No. 3, 330-331. http://dx.doi.org/10.1039/b314030j
[38]	Coates, G.W. (2000) Precise Control of Polyolefin Stereochemistry Using Single-Site Metal Catalysts. Chemical Reviews, 100, 1223-1252. http://dx.doi.org/10.1021/cr990286u
[39]	Nimitsiriwat, N., Marshall, E.L., Gibson, V.C., Elsegood, M.R.J. and Dale, S.H. (2004) Unprecedented Reversible Migration of Amide to Schiff Base Ligands Attached to Tin: Latent Single-Site Initiators for Lactide Polymerization. Journal of the American Chemical Society, 126, 13598-13599. http://dx.doi.org/10.1021/ja0470315
[40]	Chisholm, M.H., Eilerts, N.W., Huffman, J.C., Iyer, S.S., Pacold, M. and Phomphrai, K. (2000) Molecular Design of Single-Site Metal Alkoxide Catalyst Precursors for Ring-Opening Polymerization Reactions Leading to Polyoxygenates. 1. Polylactide Formation by Achiral and Chiral Magnesium and Zinc Alkoxides, (η3-L)MOR, Where L=Trispyrazolyl- and Trisindazolylborate Ligands. Journal of the American Chemical Society, 122, 11845-11854. http://dx.doi.org/10.1021/ja002160g
[41]	Cai, C.X., Toupet, L., Lehmann, C.W. and Carpentier, J.-F. (2003) Synthesis, Structure and Reactivity of New Yttrium Bis(dimethylsilyl) Amido and Bis(trimethylsilyl) Methyl Complexes of a Tetradentate Bis(phenoxide) Ligand. Journal of Organometallic Chemistry, 683, 131-136. http://dx.doi.org/10.1016/S0022-328X(03)00513-8
[42]	Chamberlain, B.M., Cheng, M., Moore, D.R., Ovitt, T.M., Lobkovsky, E.B. and Coates, G.W. (2001) Polymerization of Lactide with Zinc and Magnesium β-Diiminate Complexes: Stereocontrol and Mechanism. Journal of the American Chemical Society, 123, 3229-3238. http://dx.doi.org/10.1021/ja003851f
[43]	Kowalski, A., Duda, A. and Penczek, S. (1998) Polymerization of L,L-Lactide Initiated by Aluminum Isopropoxide Trimer or Tetramer. Macromolecules, 31, 2114-2122. http://dx.doi.org/10.1021/ma971737k
[44]	Dove, A.P., Gibson, V.C., Marshall, E.L., White, A.J.P. and Williams, D. (2001) A Well Defined Tin(II) Initiator for the Living Polymerisation of Lactide. Chemical Communications, No. 3, 283-284. http://dx.doi.org/10.1039/b008770j
[45]	Grunova, E., Kirillov, E., Roisnel, T. and Carpentier, J.-F. (2008) Group 3 Metal Complexes of Salen-Like FluorousDialkoxy-Diimino Ligands: Synthesis, Structure and Application in Ring-Opening Polymerization of rac-Lactide and rac-β-Butyrolactone. Organometallics, 27, 5691-5698. http://dx.doi.org/10.1021/om800611c
[46]	Binda, P.I., Delbridge, E.E., Dugah, D.T., Skelton, B.W. and White, A.H. (2008) Synthesis and Structural Characterization of Some Potassium Complexes of Some Bis(phenolate) Ligands and Some Novel Heterobimetallic Binuclear Arrays Formed with Trivalent Lanthanoid Ions. Zeitschrift für anorganische und allgemeine Chemie, 634, 325-334. http://dx.doi.org/10.1002/zaac.200700442
[47]	Cortright, S.B. and Johnston, J.N. (2002) IAN-Amines: Direct Entry to a Chiral C2-Symmetric Zirconium(IV) β-Diketimine Complex. Angewandte Chemie International Edition, 41, 345-348. http://dx.doi.org/10.1002/1521-3773(20020118)41:2<345::AID-ANIE345>3.0.CO;2-U.