Template-directed dynamic synthesis of mechanically interlocked dendrimers

Journal of the American Chemical Society

Volumn 127, Issue 16, 2005, Pages 5808-5810

  Leung, Ken C F ^a   Aricó, Fabio ^a   Cantrill, Stuart J ^a   Stoddart, J Fraser ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALDEHYDE DERIVATIVE; DENDRIMER; DIAMINE; MACROCYCLIC COMPOUND; ROTAXANE;

ARTICLE; CHEMICAL REACTION KINETICS; COVALENT BOND; ELECTROSPRAY MASS SPECTROMETRY; PROTON NUCLEAR MAGNETIC RESONANCE; SYNTHESIS; THERMODYNAMICS;

EID: 17744390370     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja0501363     Document Type: Article

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35. For reviews and selected publications in dendrimer chemistry, see: (a) Fréchet, J. M. J.; Tomalia, D. A. Dendrimers and Other Dendritic Polymers; Wiley: New York, 2002. (b) Newkome, G. R.; Vögtle, F.; Moorefield, C. N. Dendrimers and Dendrons: Concepts, Syntheses, Applications; VCH: New York, 2001. (c) Chow, H.-F.; Mong, T. K.-K.; Nongrum, M. F.; Wan, C.-W. Tetrahedron 1998, 8543-8660. (d) Matthews, O. A.; Shipway, A. N.; Stoddart, J. F. Prog. Polym. Sci. 1998, 23, 1-56. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev. 1999, 99, 1665-1688. (f) Stoddart, F. J.; Welton, T. Polyhedron 1999, 18, 3575-3591. (g) Vögtle, F.; Gestermann, S.; Hesse, R.; Schwierz, H.; Windisch, B. Prog. Polym. Sci. 2000, 25, 987-1041.
36. For reviews and selected publications in dendrimer chemistry, see: (a) Fréchet, J. M. J.; Tomalia, D. A. Dendrimers and Other Dendritic Polymers; Wiley: New York, 2002. (b) Newkome, G. R.; Vögtle, F.; Moorefield, C. N. Dendrimers and Dendrons: Concepts, Syntheses, Applications; VCH: New York, 2001. (c) Chow, H.-F.; Mong, T. K.-K.; Nongrum, M. F.; Wan, C.-W. Tetrahedron 1998, 8543-8660. (d) Matthews, O. A.; Shipway, A. N.; Stoddart, J. F. Prog. Polym. Sci. 1998, 23, 1-56. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev. 1999, 99, 1665-1688. (f) Stoddart, F. J.; Welton, T. Polyhedron 1999, 18, 3575-3591. (g) Vögtle, F.; Gestermann, S.; Hesse, R.; Schwierz, H.; Windisch, B. Prog. Polym. Sci. 2000, 25, 987-1041.
37. For reviews and selected publications in dendrimer chemistry, see: (a) Fréchet, J. M. J.; Tomalia, D. A. Dendrimers and Other Dendritic Polymers; Wiley: New York, 2002. (b) Newkome, G. R.; Vögtle, F.; Moorefield, C. N. Dendrimers and Dendrons: Concepts, Syntheses, Applications; VCH: New York, 2001. (c) Chow, H.-F.; Mong, T. K.-K.; Nongrum, M. F.; Wan, C.-W. Tetrahedron 1998, 8543-8660. (d) Matthews, O. A.; Shipway, A. N.; Stoddart, J. F. Prog. Polym. Sci. 1998, 23, 1-56. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev. 1999, 99, 1665-1688. (f) Stoddart, F. J.; Welton, T. Polyhedron 1999, 18, 3575-3591. (g) Vögtle, F.; Gestermann, S.; Hesse, R.; Schwierz, H.; Windisch, B. Prog. Polym. Sci. 2000, 25, 987-1041.
38. For reviews and selected publications in dendrimer chemistry, see: (a) Fréchet, J. M. J.; Tomalia, D. A. Dendrimers and Other Dendritic Polymers; Wiley: New York, 2002. (b) Newkome, G. R.; Vögtle, F.; Moorefield, C. N. Dendrimers and Dendrons: Concepts, Syntheses, Applications; VCH: New York, 2001. (c) Chow, H.-F.; Mong, T. K.-K.; Nongrum, M. F.; Wan, C.-W. Tetrahedron 1998, 8543-8660. (d) Matthews, O. A.; Shipway, A. N.; Stoddart, J. F. Prog. Polym. Sci. 1998, 23, 1-56. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev. 1999, 99, 1665-1688. (f) Stoddart, F. J.; Welton, T. Polyhedron 1999, 18, 3575-3591. (g) Vögtle, F.; Gestermann, S.; Hesse, R.; Schwierz, H.; Windisch, B. Prog. Polym. Sci. 2000, 25, 987-1041.
39. For reviews and selected publications in dendrimer chemistry, see: (a) Fréchet, J. M. J.; Tomalia, D. A. Dendrimers and Other Dendritic Polymers; Wiley: New York, 2002. (b) Newkome, G. R.; Vögtle, F.; Moorefield, C. N. Dendrimers and Dendrons: Concepts, Syntheses, Applications; VCH: New York, 2001. (c) Chow, H.-F.; Mong, T. K.-K.; Nongrum, M. F.; Wan, C.-W. Tetrahedron 1998, 8543-8660. (d) Matthews, O. A.; Shipway, A. N.; Stoddart, J. F. Prog. Polym. Sci. 1998, 23, 1-56. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev. 1999, 99, 1665-1688. (f) Stoddart, F. J.; Welton, T. Polyhedron 1999, 18, 3575-3591. (g) Vögtle, F.; Gestermann, S.; Hesse, R.; Schwierz, H.; Windisch, B. Prog. Polym. Sci. 2000, 25, 987-1041.
40. For reviews and selected publications in dendrimer chemistry, see: (a) Fréchet, J. M. J.; Tomalia, D. A. Dendrimers and Other Dendritic Polymers; Wiley: New York, 2002. (b) Newkome, G. R.; Vögtle, F.; Moorefield, C. N. Dendrimers and Dendrons: Concepts, Syntheses, Applications; VCH: New York, 2001. (c) Chow, H.-F.; Mong, T. K.-K.; Nongrum, M. F.; Wan, C.-W. Tetrahedron 1998, 8543-8660. (d) Matthews, O. A.; Shipway, A. N.; Stoddart, J. F. Prog. Polym. Sci. 1998, 23, 1-56. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev. 1999, 99, 1665-1688. (f) Stoddart, F. J.; Welton, T. Polyhedron 1999, 18, 3575-3591. (g) Vögtle, F.; Gestermann, S.; Hesse, R.; Schwierz, H.; Windisch, B. Prog. Polym. Sci. 2000, 25, 987-1041.
41. For examples of dendritic pseudorotaxanes/rotaxanes, see: (a) Amabilino, D. B.; Ashton, P. R.; Balzani, V.; Brown, C. L.; Credi, A.; Fréchet, J. M. J.; Leon, J. W.; Raymo, F. M.; Spencer, N.; Stoddart, J. F.; Venturi, M. J. Am. Chem. Soc. 1996, 118, 12012-12020. (b) Yamaguchi, N.; Hamilton, L. M.; Gibson, H. W. Angew. Chem., Int. Ed. 1998, 37, 3275-3279. (c) Hübner, G. M.; Nachtsheim, G.; Li, Q. Y.; Seel, C.; Vögtle, F. Angew. Chem., Int. Ed. 2000, 39, 1269-1272. (d) Osswald, F.; Vogel, E.; Safarowsky, O.; Schwanke, F.; Vögtle, F. Adv. Synth. Catal. 2001, 343, 303-309. (e) Gibson, H. W.; Yamaguchi, N.; Hamilton, L. M.; Jones, J. W. J. Am. Chem. Soc. 2002, 124, 4653-4665. (f) Jones, J. W.; Bryant, W. S.; Bosman, A. W.; Janssen, R. A. J.; Meijer, E. W.; Gibson, H. W. J. Org. Chem. 2003, 68, 2385-2389.
42. For examples of dendritic pseudorotaxanes/rotaxanes, see: (a) Amabilino, D. B.; Ashton, P. R.; Balzani, V.; Brown, C. L.; Credi, A.; Fréchet, J. M. J.; Leon, J. W.; Raymo, F. M.; Spencer, N.; Stoddart, J. F.; Venturi, M. J. Am. Chem. Soc. 1996, 118, 12012-12020. (b) Yamaguchi, N.; Hamilton, L. M.; Gibson, H. W. Angew. Chem., Int. Ed. 1998, 37, 3275-3279. (c) Hübner, G. M.; Nachtsheim, G.; Li, Q. Y.; Seel, C.; Vögtle, F. Angew. Chem., Int. Ed. 2000, 39, 1269-1272. (d) Osswald, F.; Vogel, E.; Safarowsky, O.; Schwanke, F.; Vögtle, F. Adv. Synth. Catal. 2001, 343, 303-309. (e) Gibson, H. W.; Yamaguchi, N.; Hamilton, L. M.; Jones, J. W. J. Am. Chem. Soc. 2002, 124, 4653-4665. (f) Jones, J. W.; Bryant, W. S.; Bosman, A. W.; Janssen, R. A. J.; Meijer, E. W.; Gibson, H. W. J. Org. Chem. 2003, 68, 2385-2389.
43. For examples of dendritic pseudorotaxanes/rotaxanes, see: (a) Amabilino, D. B.; Ashton, P. R.; Balzani, V.; Brown, C. L.; Credi, A.; Fréchet, J. M. J.; Leon, J. W.; Raymo, F. M.; Spencer, N.; Stoddart, J. F.; Venturi, M. J. Am. Chem. Soc. 1996, 118, 12012-12020. (b) Yamaguchi, N.; Hamilton, L. M.; Gibson, H. W. Angew. Chem., Int. Ed. 1998, 37, 3275-3279. (c) Hübner, G. M.; Nachtsheim, G.; Li, Q. Y.; Seel, C.; Vögtle, F. Angew. Chem., Int. Ed. 2000, 39, 1269-1272. (d) Osswald, F.; Vogel, E.; Safarowsky, O.; Schwanke, F.; Vögtle, F. Adv. Synth. Catal. 2001, 343, 303-309. (e) Gibson, H. W.; Yamaguchi, N.; Hamilton, L. M.; Jones, J. W. J. Am. Chem. Soc. 2002, 124, 4653-4665. (f) Jones, J. W.; Bryant, W. S.; Bosman, A. W.; Janssen, R. A. J.; Meijer, E. W.; Gibson, H. W. J. Org. Chem. 2003, 68, 2385-2389.
44. For examples of dendritic pseudorotaxanes/rotaxanes, see: (a) Amabilino, D. B.; Ashton, P. R.; Balzani, V.; Brown, C. L.; Credi, A.; Fréchet, J. M. J.; Leon, J. W.; Raymo, F. M.; Spencer, N.; Stoddart, J. F.; Venturi, M. J. Am. Chem. Soc. 1996, 118, 12012-12020. (b) Yamaguchi, N.; Hamilton, L. M.; Gibson, H. W. Angew. Chem., Int. Ed. 1998, 37, 3275-3279. (c) Hübner, G. M.; Nachtsheim, G.; Li, Q. Y.; Seel, C.; Vögtle, F. Angew. Chem., Int. Ed. 2000, 39, 1269-1272. (d) Osswald, F.; Vogel, E.; Safarowsky, O.; Schwanke, F.; Vögtle, F. Adv. Synth. Catal. 2001, 343, 303-309. (e) Gibson, H. W.; Yamaguchi, N.; Hamilton, L. M.; Jones, J. W. J. Am. Chem. Soc. 2002, 124, 4653-4665. (f) Jones, J. W.; Bryant, W. S.; Bosman, A. W.; Janssen, R. A. J.; Meijer, E. W.; Gibson, H. W. J. Org. Chem. 2003, 68, 2385-2389.
45. For examples of dendritic pseudorotaxanes/rotaxanes, see: (a) Amabilino, D. B.; Ashton, P. R.; Balzani, V.; Brown, C. L.; Credi, A.; Fréchet, J. M. J.; Leon, J. W.; Raymo, F. M.; Spencer, N.; Stoddart, J. F.; Venturi, M. J. Am. Chem. Soc. 1996, 118, 12012-12020. (b) Yamaguchi, N.; Hamilton, L. M.; Gibson, H. W. Angew. Chem., Int. Ed. 1998, 37, 3275-3279. (c) Hübner, G. M.; Nachtsheim, G.; Li, Q. Y.; Seel, C.; Vögtle, F. Angew. Chem., Int. Ed. 2000, 39, 1269-1272. (d) Osswald, F.; Vogel, E.; Safarowsky, O.; Schwanke, F.; Vögtle, F. Adv. Synth. Catal. 2001, 343, 303-309. (e) Gibson, H. W.; Yamaguchi, N.; Hamilton, L. M.; Jones, J. W. J. Am. Chem. Soc. 2002, 124, 4653-4665. (f) Jones, J. W.; Bryant, W. S.; Bosman, A. W.; Janssen, R. A. J.; Meijer, E. W.; Gibson, H. W. J. Org. Chem. 2003, 68, 2385-2389.
46. For examples of dendritic pseudorotaxanes/rotaxanes, see: (a) Amabilino, D. B.; Ashton, P. R.; Balzani, V.; Brown, C. L.; Credi, A.; Fréchet, J. M. J.; Leon, J. W.; Raymo, F. M.; Spencer, N.; Stoddart, J. F.; Venturi, M. J. Am. Chem. Soc. 1996, 118, 12012-12020. (b) Yamaguchi, N.; Hamilton, L. M.; Gibson, H. W. Angew. Chem., Int. Ed. 1998, 37, 3275-3279. (c) Hübner, G. M.; Nachtsheim, G.; Li, Q. Y.; Seel, C.; Vögtle, F. Angew. Chem., Int. Ed. 2000, 39, 1269-1272. (d) Osswald, F.; Vogel, E.; Safarowsky, O.; Schwanke, F.; Vögtle, F. Adv. Synth. Catal. 2001, 343, 303-309. (e) Gibson, H. W.; Yamaguchi, N.; Hamilton, L. M.; Jones, J. W. J. Am. Chem. Soc. 2002, 124, 4653-4665. (f) Jones, J. W.; Bryant, W. S.; Bosman, A. W.; Janssen, R. A. J.; Meijer, E. W.; Gibson, H. W. J. Org. Chem. 2003, 68, 2385-2389.
47. 2 at 40°C, bis(cyclohexylmethyl)ammonium hexafluorophosphate (50 mM) is converted 98% of the way to a [2]rotaxane in the presence of 150 mM of dibenzo[24]crown-8 (DB24C8). In the event, this thermodynamically controlled self-assembly process lost all its remarkable efficiency on going from the model system to one that involves a Fréchet-type benzyl ether wedge and a DB24C8 unit which links another two such wedges. The best yield of a mechanically interlocked dendrimer that could be obtained in this single slippage experiment was 19%, and this result involved a 90 day reaction period, followed by chromatography! This outcome was not exactly encouraging, and it took a considerable act of faith not to abandon a thermodynamically controlled approach to the synthesis of dendrimers containing mechanical bonds. It was against this background that we decided to explore the convergent template procedure, involving DCC in the context of imine bond formation. The fact that this one-step procedure goes in excess of 90% tells us that finally, at the third attempt, we have come up with a method that works that is sufficiently efficient to be of practical use in the synthesis of mechanically interlocked dendrimers.
48. 2 at 40°C, bis(cyclohexylmethyl)ammonium hexafluorophosphate (50 mM) is converted 98% of the way to a [2]rotaxane in the presence of 150 mM of dibenzo[24]crown-8 (DB24C8). In the event, this thermodynamically controlled self-assembly process lost all its remarkable efficiency on going from the model system to one that involves a Fréchet-type benzyl ether wedge and a DB24C8 unit which links another two such wedges. The best yield of a mechanically interlocked dendrimer that could be obtained in this single slippage experiment was 19%, and this result involved a 90 day reaction period, followed by chromatography! This outcome was not exactly encouraging, and it took a considerable act of faith not to abandon a thermodynamically controlled approach to the synthesis of dendrimers containing mechanical bonds. It was against this background that we decided to explore the convergent template procedure, involving DCC in the context of imine bond formation. The fact that this one-step procedure goes in excess of 90% tells us that finally, at the third attempt, we have come up with a method that works that is sufficiently efficient to be of practical use in the synthesis of mechanically interlocked dendrimers.
49. 2 at 40°C, bis(cyclohexylmethyl)ammonium hexafluorophosphate (50 mM) is converted 98% of the way to a [2]rotaxane in the presence of 150 mM of dibenzo[24]crown-8 (DB24C8). In the event, this thermodynamically controlled self-assembly process lost all its remarkable efficiency on going from the model system to one that involves a Fréchet-type benzyl ether wedge and a DB24C8 unit which links another two such wedges. The best yield of a mechanically interlocked dendrimer that could be obtained in this single slippage experiment was 19%, and this result involved a 90 day reaction period, followed by chromatography! This outcome was not exactly encouraging, and it took a considerable act of faith not to abandon a thermodynamically controlled approach to the synthesis of dendrimers containing mechanical bonds. It was against this background that we decided to explore the convergent template procedure, involving DCC in the context of imine bond formation. The fact that this one-step procedure goes in excess of 90% tells us that finally, at the third attempt, we have come up with a method that works that is sufficiently efficient to be of practical use in the synthesis of mechanically interlocked dendrimers.
50. Stoddart, A. et al. Helv. Chim. Acta 2001, 84, 296-334.
51. 2 (65 mM) to afford a mixture of nine dynamic dendrimers in one pot. ESI-MS revealed the absence of the [G2]/[G2]/[G2] dynamic dendrimer in the mixture but the presence of all other eight dendrimers, with different combinations of dendron generations in almost equal amounts, with the exception of the [G0]/[G0]/[G0] dynamic dendrimer, which was observed in only a trace amount.