Dendrimers based on melamine. Divergent and orthogonal, convergent syntheses of a G3 dendrimer

Organic Letters

Volumn 2, Issue 6, 2000, Pages 843-845

  Zhang, Wen ^a   Simanek, Eric E ^a  

^a TEXAS A AND M UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001620656     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol005585g     Document Type: Article

References (15)

1. For recent reviews of dendrimer chemistry, see: (a) Newkome, G. R.; Moorefield, C. N.; Vogtle, F. Dendritic Macromolecules; VCH: New York, 1996.
2. (b) Newkome, G. R.; He, E.; Moorefield, C. N. Chem. Rev. 1999, 99, 1689.
3. (c) Frechet, J. M. J. Science 1994, 263, 1710.
4. (d) Fisher, M.; Vogtle, F. Angew. Chem., Int. Ed. Engl. 1999, 38, 4000.
5. (e) Bosman, A. W.; Janssen, H. M.; Meijer, E. J. Chem. Rev. 1999, 99, 1665.
6. For a review of molecular recognition using melamine, see: Whitesides, G. M.; Simanek, E. E.; Mathias, J. P.; Seto, C. T.; Chin, D. N.; Mammen, M.; Gordon, D. M. Acc. Chem. Res. 1995, 28, 37 and references therein.
7. Newkome and co-workers have incorporated 1,5-diaminopyridine units into dendrimers and examined the ability of these molecules to recognize barbituric acid derivatives: Newkome, G. R.; Woolsey, B. D.; He, E.; Moorefield, C. N.; Guther, R.; Baker, G. R.; Escamilla, G. H.; Merill, J.; Luftmann, H. Chem. Commun. 1996, 2737.
8. Hawker, C. J.; Frechet, J. M. J. J. Am. Chem. Soc. 1990, 112, 7638.
9. Tomalia, D. A.; Durst, H. D. Top. Curr. Chem. 1993, 765, 193.
10. Moorefield, C. N.; Newkome, G. R.; Baker, G. R. Aldrichimica Acta 1992, 25, 31.
11. Zimmerman employs alternating Mitsunobu esterifications and Sonogashira couplings (of terminal acetylenes with aryl iodides) to build G4 and G6 dendrimers; see: Zeng. F.; Zimmerman, S. C. J. Am. Chem. Soc. 1996, 118, 5326.
12. Frechet's strategy relies on alternating carboxylate alkylations and DCC-mediated esterifications to build G4 dendrimers; see: (a) Spindler, R.; Frechet, J. M. J. J. Chem. Soc., Perkins Trans, 1 1993, 913.
13. (b) Freeman, A. W.; Frechet, J. M. J. Org. Lett. 1999, 1, 685.
14. 3 is shown to illustrate the generality of the pattern of lines; slight deviations in chemical shift can be seen.
15. Lines corresponding to "a" for both 8 and 10 are not discernible in Figure 1. These peaks both appear at 169 ppm.