Protected amino acid chlorides vs protected amino acid fluorides: Reactivity comparisons

Tetrahedron Letters

Volumn 39, Issue 3-4, 1998, Pages 241-244

  Carpino, Louis A ^a   Ionescu, Dumitru ^a,d   El Faham, Ayman ^a,e   Henklein, Petra ^b   Wenschuh, Holger ^c   Bienert, Michael ^b   Beyermann, Michael ^b  

^a UNIVERSITY OF MASSACHUSETTS   (United States)

^b LEIBNIZ INSTITUT FÜR MOLEKULARE PHARMAKOLOGIE   (Germany)

^c MAX PLANCK INSTITUTE FOR INFECTION BIOLOGY   (Germany)

^d UNIVERSITY OF BUCHAREST   (Romania)

^e Alexandria University Faculty Of Science   (Egypt)

Author keywords

[No Author keywords available]

Indexed keywords

AMINO ACID DERIVATIVE; CHLORIDE; FLUORIDE; FUNCTIONAL GROUP; REAGENT;

ARTICLE; CATALYSIS; CHEMICAL BOND; CHEMICAL REACTION; PROTECTION; REACTION ANALYSIS;

EID: 0032518778     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(97)10504-4     Document Type: Article

References (24)

1. 1. For a brief review on the reactivity of protected amino acid halides and references to previous studies on the reactivity of simple acid halides, see (a) Carpino, L. A.; Beyermann, M.; Wenschuh, H.; Bienert, M. Acct. Chem. Research. 1996, 29(6), 268 and
2. (b) Footnote 11 of ref. 6.
3. 2. Recently a similar effect was reported in which the alkoxide anion derived from a highly hindered alcohol reacted with a cyclohexenecarboxylic acid fluoride to give the ester in significantly higher yield (70%) than the corresponding acid chloride (35%). See Mayer, S.; Joullie, M. M. Syn. Commun. 1994, 24, 2367.
4. 3. Bender, M. L.; Jones, J. M. J. Org. Chem. 1962, 27, 3771.
5. 4. Bunnett, J. F.; Garbisch, E. W. Jr., Pruitt, K. M. J. Am. Chem. Soc. 1957, 79, 385.
6. 5. (a) Benoiton, N. L. Biopolymers 1996, 40, 245;
7. (b) Carpino, L. A.; Chao, H.-G.; Beyermann, M.; Bienert, M. J. Org. Chem. 1991, 56, 2635.
8. 6. Carpino, L. A.; Sadat-Aalaee, D.; Chao, H.-G.; DeSelms, R. H. J. Amer. Chem. Soc. 1990, 112, 9651.
9. 7. Carpino, L. A.; El-Faham, A. J. Am. Chem. Soc. 1995, 117, 5401, footnote 20.
10. 8 (a) Wenschuh, H.; Beyermann, M.; Krause, E.; Brudel, M.; Winter, R.; Schümann, M.; Carpino, L. A.; Bienert, M. J. Org. Chem. 1994, 59, 3275.
11. (b) Wenschuh, H.; Beyermann, M.; Haber, H.; Seydel, J. K.; Krause, E.; Bienert, M.; Carpino, L. A.; El-Faham, A. J. Org. Chem. 1995, 60, 405.
12. 9. Wenschuh, H.; Beyermann, M.; Winter, R.; Bienert, M.; Ionescu, D.; Carpino, L. A. Tetrahedron Lett. 1996, 37, 5483.
13. 10. BSA may act both as base and N-silylating agent. The effect of prior silylation on coupling processes carried out using amino acid halides will be described in the full description of this work.
14. 11. Leplawy, M. T.; Jones, D. S.; Kenner, g. W.; Sheppard, R. C. Tetrahedron 1990, 11, 39.
15. 12. Moretto, V.; Valle, G.; Crisma, M.; Bonora, G. M.; Toniolo, C. Int. J. Biol. Macromol. 1992, 14, 178.
16. 13. Spencer, J. R., Antonenko, V. W.; Delaet, N. G. J.; Goodman, M. Int. J. Pept. Prot. Res. 1992, 40, 282.
17. 14. (a) Wiley, R. H.; Miller, J. G.; Day, A. R. J. Am. Chem. Soc. 1954, 72, 3496;
18. (b) Beecham, A. F. J. Am. Chem. Soc. 1957, 79, 3527.
19. 15. (a) Price, C. C.; Oae, S. Sulfur Bonding, Ronald Press, New York, NY, 1962, p. 120;
20. (b) A similar effect may be operative in the greater Friedel-Crafts reactivity of N-phthaloylamino acid chlorides relative to N-methoxycarbonylamino acid chlorides. See Effenberger, F.; Steegmüller, D. Chem. Ber. 1988, 121, 117.
21. 16. Carpino, L. A.; Shroff, H., Triolo, S. A.; Mansour, E. M. E.; Wenschuh, H.; Albericio, F. Tetrahedron Lett. 1993, 34, 7829. Two alternative easily-deblocked heteroarenesulfonamide amino acid protectants have recently been described: Vedejs, E.; Lin, S.; Klapars, A.; Wang, J. J. Am. Chem. Soc. 1996, 118. 9796. This work also described the greater reactivity of a sulfonamide-protected amino acid chloride relative to a urethane-protected amino acid fluoride. For a comparison of azido acid chlorides and the corresponding acid fluorides see Meldal, M.; Juliano, M. A.; Jansson, A. M. Tetrahedron Lett. 1997, 38, 2531.
22. 16. Carpino, L. A.; Shroff, H., Triolo, S. A.; Mansour, E. M. E.; Wenschuh, H.; Albericio, F. Tetrahedron Lett. 1993, 34, 7829. Two alternative easily-deblocked heteroarenesulfonamide amino acid protectants have recently been described: Vedejs, E.; Lin, S.; Klapars, A.; Wang, J. J. Am. Chem. Soc. 1996, 118. 9796. This work also described the greater reactivity of a sulfonamide-protected amino acid chloride relative to a urethane-protected amino acid fluoride. For a comparison of azido acid chlorides and the corresponding acid fluorides see Meldal, M.; Juliano, M. A.; Jansson, A. M. Tetrahedron Lett. 1997, 38, 2531.
23. 16. Carpino, L. A.; Shroff, H., Triolo, S. A.; Mansour, E. M. E.; Wenschuh, H.; Albericio, F. Tetrahedron Lett. 1993, 34, 7829. Two alternative easily-deblocked heteroarenesulfonamide amino acid protectants have recently been described: Vedejs, E.; Lin, S.; Klapars, A.; Wang, J. J. Am. Chem. Soc. 1996, 118. 9796. This work also described the greater reactivity of a sulfonamide-protected amino acid chloride relative to a urethane-protected amino acid fluoride. For a comparison of azido acid chlorides and the corresponding acid fluorides see Meldal, M.; Juliano, M. A.; Jansson, A. M. Tetrahedron Lett. 1997, 38, 2531.
24. 6S: C, 59.75; H, 7.88, N, 5.81. Found: C, 59.33; H, 7.66; N, 5.81. Cleavage of the Pbf group was carried out by treatment of 1 mg of the protected dipeptide with 100 μL of 10% dimethyl sulfide (DMS) in TFA. After 1 h deprotection was complete and the reaction mixture was worked up by ether precipitation to give 0.4 mg (86%) of the dipeptide methyl ester TFA salt, mp 162-164°C, ES-MS 231 (M+1), calcd 230 (M).