Preparation of achiral and of enantiopure geminally disubstituted β- amino acids for β-peptide synthesis

European Journal of Organic Chemistry

Volumn , Issue 1, 2000, Pages 1-15

  Abele, Stefan ^a   Seebach, Dieter ^a  

^a ETH ZURICH   (Switzerland)

Author keywords

Chirality; Stereoselectivity; Amino acids; Peptides

Indexed keywords

BETA AMINO ACID; SYNTHETIC PEPTIDE;

ALKYLATION; CHIRALITY; ENANTIOMER; PEPTIDE ANALYSIS; PEPTIDE SYNTHESIS; SHORT SURVEY; STEREOCHEMISTRY;

EID: 0033986387     PISSN: 1434193X     EISSN: None     Source Type: Journal    
DOI: 10.1002/(SICI)1099-0690(200001)2000:1<1::AID-EJOC1>3.0.CO;2-6     Document Type: Short Survey

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83. Methods for preparing doubly alkylated aspartic acid, which is both an α,α-disubstituted α-amino acid and a β,β-disubstituted β-amino acid, are not discussed here; see D. Seebach, D. Wasmuth, Angew. Chem. 1981, 93, 1007-1008; Angew. Chem. Int. Ed. Engl. 1981, 20, 971; J. D. Aebi, D. Seebach, Helv. Chim. Acta 1985, 68, 1507-1528; A. Fadel, J. Salaün, Tetrahedron Lett. 1987, 28, 2243-2246; G. I. Georg, X. Guan, J. Kant, Tetrahedron Lett. 1988, 29, 403-406; C.-O. Chan, D. Crich, Tetrahedron Lett. 1992, 33, 3405-3408; D. Obrecht, O. Bohdal, C. Lehmann, P. Schönholzer, K. Müller, Tetrahedron 1995, 51, 10883-10900; C. Cativiela, M. D. Díaz-de-Villegas, J. A. Gálvez, Y. Lapena, Tetrahedron 1997, 53, 5891-5898; E. Juaristi, H. López-Ruiz, D. Madrigal, Y. Ramírez-Quirós, J. Escalante, J. Org. Chem. 1998, 63, 4706-4710.
84. Methods for preparing doubly alkylated aspartic acid, which is both an α,α-disubstituted α-amino acid and a β,β-disubstituted β-amino acid, are not discussed here; see D. Seebach, D. Wasmuth, Angew. Chem. 1981, 93, 1007-1008; Angew. Chem. Int. Ed. Engl. 1981, 20, 971; J. D. Aebi, D. Seebach, Helv. Chim. Acta 1985, 68, 1507-1528; A. Fadel, J. Salaün, Tetrahedron Lett. 1987, 28, 2243-2246; G. I. Georg, X. Guan, J. Kant, Tetrahedron Lett. 1988, 29, 403-406; C.-O. Chan, D. Crich, Tetrahedron Lett. 1992, 33, 3405-3408; D. Obrecht, O. Bohdal, C. Lehmann, P. Schönholzer, K. Müller, Tetrahedron 1995, 51, 10883-10900; C. Cativiela, M. D. Díaz-de-Villegas, J. A. Gálvez, Y. Lapena, Tetrahedron 1997, 53, 5891-5898; E. Juaristi, H. López-Ruiz, D. Madrigal, Y. Ramírez-Quirós, J. Escalante, J. Org. Chem. 1998, 63, 4706-4710.
85. Methods for preparing doubly alkylated aspartic acid, which is both an α,α-disubstituted α-amino acid and a β,β-disubstituted β-amino acid, are not discussed here; see D. Seebach, D. Wasmuth, Angew. Chem. 1981, 93, 1007-1008; Angew. Chem. Int. Ed. Engl. 1981, 20, 971; J. D. Aebi, D. Seebach, Helv. Chim. Acta 1985, 68, 1507-1528; A. Fadel, J. Salaün, Tetrahedron Lett. 1987, 28, 2243-2246; G. I. Georg, X. Guan, J. Kant, Tetrahedron Lett. 1988, 29, 403-406; C.-O. Chan, D. Crich, Tetrahedron Lett. 1992, 33, 3405-3408; D. Obrecht, O. Bohdal, C. Lehmann, P. Schönholzer, K. Müller, Tetrahedron 1995, 51, 10883-10900; C. Cativiela, M. D. Díaz-de-Villegas, J. A. Gálvez, Y. Lapena, Tetrahedron 1997, 53, 5891-5898; E. Juaristi, H. López-Ruiz, D. Madrigal, Y. Ramírez-Quirós, J. Escalante, J. Org. Chem. 1998, 63, 4706-4710.
86. Methods for preparing doubly alkylated aspartic acid, which is both an α,α-disubstituted α-amino acid and a β,β-disubstituted β-amino acid, are not discussed here; see D. Seebach, D. Wasmuth, Angew. Chem. 1981, 93, 1007-1008; Angew. Chem. Int. Ed. Engl. 1981, 20, 971; J. D. Aebi, D. Seebach, Helv. Chim. Acta 1985, 68, 1507-1528; A. Fadel, J. Salaün, Tetrahedron Lett. 1987, 28, 2243-2246; G. I. Georg, X. Guan, J. Kant, Tetrahedron Lett. 1988, 29, 403-406; C.-O. Chan, D. Crich, Tetrahedron Lett. 1992, 33, 3405-3408; D. Obrecht, O. Bohdal, C. Lehmann, P. Schönholzer, K. Müller, Tetrahedron 1995, 51, 10883-10900; C. Cativiela, M. D. Díaz-de-Villegas, J. A. Gálvez, Y. Lapena, Tetrahedron 1997, 53, 5891-5898; E. Juaristi, H. López-Ruiz, D. Madrigal, Y. Ramírez-Quirós, J. Escalante, J. Org. Chem. 1998, 63, 4706-4710.
87. Methods for preparing doubly alkylated aspartic acid, which is both an α,α-disubstituted α-amino acid and a β,β-disubstituted β-amino acid, are not discussed here; see D. Seebach, D. Wasmuth, Angew. Chem. 1981, 93, 1007-1008; Angew. Chem. Int. Ed. Engl. 1981, 20, 971; J. D. Aebi, D. Seebach, Helv. Chim. Acta 1985, 68, 1507-1528; A. Fadel, J. Salaün, Tetrahedron Lett. 1987, 28, 2243-2246; G. I. Georg, X. Guan, J. Kant, Tetrahedron Lett. 1988, 29, 403-406; C.-O. Chan, D. Crich, Tetrahedron Lett. 1992, 33, 3405-3408; D. Obrecht, O. Bohdal, C. Lehmann, P. Schönholzer, K. Müller, Tetrahedron 1995, 51, 10883-10900; C. Cativiela, M. D. Díaz-de-Villegas, J. A. Gálvez, Y. Lapena, Tetrahedron 1997, 53, 5891-5898; E. Juaristi, H. López-Ruiz, D. Madrigal, Y. Ramírez-Quirós, J. Escalante, J. Org. Chem. 1998, 63, 4706-4710.
88. Methods for preparing doubly alkylated aspartic acid, which is both an α,α-disubstituted α-amino acid and a β,β-disubstituted β-amino acid, are not discussed here; see D. Seebach, D. Wasmuth, Angew. Chem. 1981, 93, 1007-1008; Angew. Chem. Int. Ed. Engl. 1981, 20, 971; J. D. Aebi, D. Seebach, Helv. Chim. Acta 1985, 68, 1507-1528; A. Fadel, J. Salaün, Tetrahedron Lett. 1987, 28, 2243-2246; G. I. Georg, X. Guan, J. Kant, Tetrahedron Lett. 1988, 29, 403-406; C.-O. Chan, D. Crich, Tetrahedron Lett. 1992, 33, 3405-3408; D. Obrecht, O. Bohdal, C. Lehmann, P. Schönholzer, K. Müller, Tetrahedron 1995, 51, 10883-10900; C. Cativiela, M. D. Díaz-de-Villegas, J. A. Gálvez, Y. Lapena, Tetrahedron 1997, 53, 5891-5898; E. Juaristi, H. López-Ruiz, D. Madrigal, Y. Ramírez-Quirós, J. Escalante, J. Org. Chem. 1998, 63, 4706-4710.
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114. ≠ for pyramidal inversion of sulfoxides is 35-42 kcal/mol, accounting for their configurational stability at 25°C; see R. Rayner, A. J. Gordon, K. Mislow, J. Am. Chem. Soc. 1968, 90, 4854-4860. p-Toluenesulfinates, however, undergo slow acid-catalyzed mutarotation, see H. F. Herbrandson, R. T. Dickerson Jr., J. Am. Chem. Soc. 1959, 81, 4102-4106.
115. ≠ for pyramidal inversion of sulfoxides is 35-42 kcal/mol, accounting for their configurational stability at 25°C; see R. Rayner, A. J. Gordon, K. Mislow, J. Am. Chem. Soc. 1968, 90, 4854-4860. p-Toluenesulfinates, however, undergo slow acid-catalyzed mutarotation, see H. F. Herbrandson, R. T. Dickerson Jr., J. Am. Chem. Soc. 1959, 81, 4102-4106.
116. The (E)-configuration of the imine was proved by single-crystal X-ray analysis.[85]
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126. The tert-butanesulfinyl group is cleaved at room temperature by brief treatment with ethanolic HCl.
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140. 1,3-strain, see R. W. Hoffmann, Chem. Rev. 1989, 89, 1841-1860; D. A. Evans, Aldrichimica Acta 1982, 15, 23-32; J. L. Broeker, R. W. Hoffmann, K. N. Houk, J. Am. Chem. Soc: 1991, 113, 5006-5017; D. Seebach, B. Lamatsch, R. Amstutz, A. K. Beck, M. Dobler, M. Egli, R. Fitzi, M. Gautschi, B. Herradón, P. C. Hidber, J. J. Irwin, R. Locher, M. Maestro, T. Maetzke, A. Mouriño, E. Pfammatter, D. A. Plattner, C. Schickli, W. B. Schweizer, P. Seiler, G. Stucky, W. Petter, J. Escalante, E. Juaristi, D. Quintana, C. Miravitlles, E. Molins, Helv. Chim. Acta 1992, 75, 913-934. A similar situation arises with α-branched keto carboxamides with two substituents at the nitrogen atom, see S. Blank, D. Seebach, Liebigs Ann. Chem. 1993, 889-896. In the case shown in Scheme 13, the α-deprotonation was possible, probably due to small steric requirements of the cyano group.
141. 1,3-strain, see R. W. Hoffmann, Chem. Rev. 1989, 89, 1841-1860; D. A. Evans, Aldrichimica Acta 1982, 15, 23-32; J. L. Broeker, R. W. Hoffmann, K. N. Houk, J. Am. Chem. Soc: 1991, 113, 5006-5017; D. Seebach, B. Lamatsch, R. Amstutz, A. K. Beck, M. Dobler, M. Egli, R. Fitzi, M. Gautschi, B. Herradón, P. C. Hidber, J. J. Irwin, R. Locher, M. Maestro, T. Maetzke, A. Mouriño, E. Pfammatter, D. A. Plattner, C. Schickli, W. B. Schweizer, P. Seiler, G. Stucky, W. Petter, J. Escalante, E. Juaristi, D. Quintana, C. Miravitlles, E. Molins, Helv. Chim. Acta 1992, 75, 913-934. A similar situation arises with α-branched keto carboxamides with two substituents at the nitrogen atom, see S. Blank, D. Seebach, Liebigs Ann. Chem. 1993, 889-896. In the case shown in Scheme 13, the α-deprotonation was possible, probably due to small steric requirements of the cyano group.
142. 1,3-strain, see R. W. Hoffmann, Chem. Rev. 1989, 89, 1841-1860; D. A. Evans, Aldrichimica Acta 1982, 15, 23-32; J. L. Broeker, R. W. Hoffmann, K. N. Houk, J. Am. Chem. Soc: 1991, 113, 5006-5017; D. Seebach, B. Lamatsch, R. Amstutz, A. K. Beck, M. Dobler, M. Egli, R. Fitzi, M. Gautschi, B. Herradón, P. C. Hidber, J. J. Irwin, R. Locher, M. Maestro, T. Maetzke, A. Mouriño, E. Pfammatter, D. A. Plattner, C. Schickli, W. B. Schweizer, P. Seiler, G. Stucky, W. Petter, J. Escalante, E. Juaristi, D. Quintana, C. Miravitlles, E. Molins, Helv. Chim. Acta 1992, 75, 913-934. A similar situation arises with α-branched keto carboxamides with two substituents at the nitrogen atom, see S. Blank, D. Seebach, Liebigs Ann. Chem. 1993, 889-896. In the case shown in Scheme 13, the α-deprotonation was possible, probably due to small steric requirements of the cyano group.
143. 1,3-strain, see R. W. Hoffmann, Chem. Rev. 1989, 89, 1841-1860; D. A. Evans, Aldrichimica Acta 1982, 15, 23-32; J. L. Broeker, R. W. Hoffmann, K. N. Houk, J. Am. Chem. Soc: 1991, 113, 5006-5017; D. Seebach, B. Lamatsch, R. Amstutz, A. K. Beck, M. Dobler, M. Egli, R. Fitzi, M. Gautschi, B. Herradón, P. C. Hidber, J. J. Irwin, R. Locher, M. Maestro, T. Maetzke, A. Mouriño, E. Pfammatter, D. A. Plattner, C. Schickli, W. B. Schweizer, P. Seiler, G. Stucky, W. Petter, J. Escalante, E. Juaristi, D. Quintana, C. Miravitlles, E. Molins, Helv. Chim. Acta 1992, 75, 913-934. A similar situation arises with α-branched keto carboxamides with two substituents at the nitrogen atom, see S. Blank, D. Seebach, Liebigs Ann. Chem. 1993, 889-896. In the case shown in Scheme 13, the α-deprotonation was possible, probably due to small steric requirements of the cyano group.
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