Highly Symmetrical Amino Acid-Derived N,N′-Diacylated Sulfodiimines

Abstract

A mild and efficient method for the coupling of sulfodiimines with N-protected amino acids has been developed, yielding the corresponding N,N′-diacylated sulfodiimines with up to 94% yield.

coupling - amino acids - acylations - peptides - sulfodiimines - asymmetric synthesis

References

Reviews:

1a Reggelin M. Zur C. Synthesis  2000,  1 

1b Mikolajczk M. Drabowicz J. Kielbasinski P. Chiral Sulfur Reagents   CRC Press; Boca Raton: 1997. 

1c Pyne S. Sulfur Reports  1992,  12:  57 

1d Haake M. In Houben-Weyl, Methoden der organischen Chemie   Vol. E11:  Klamann D. Thieme; Stuttgart: 1985.  p.1299 

1e Johnson CR. Acc. Chem. Res.  1973,  6:  341 

1f Johnson CR. Aldrichimica Acta  1985,  18:  3 

For some recent examples stemming from this group, see:

2a Bolm C. Müller D. Dalhoff C. Hackenberger CPR. Weinhold E. Bioorg. Med. Chem. Lett.  2003,  13:  3207 

2b Bolm C. Müller D. Hackenberger CPR. Org. Lett.  2002,  4:  893 

2c Bolm C. Moll G. Kahmann JD. Chem.-Eur. J.  2001,  7:  1118 

3 Okamura H. Bolm C. Chem. Lett.  2004,  33:  482 

For recent examples, see:

4a Langner M. Bolm C. Angew. Chem. Int. Ed.  2004,  43:  5984 

4b Bolm C. Martin M. Simic O. Verrucci M. Org. Lett.  2003,  5:  427 

4c Bolm C. Verrucci M. Simic O. Cozzi PG. Raabe G. Okamura H. Chem. Commun.  2003,  2816 

4d Bolm C. Simic O. J. Am. Chem. Soc.  2001,  123:  3830 

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4f Harmata M. Ghosh SK. Org. Lett.  2001,  3:  3321 

4g See also: Bolm C. Martin M. Gescheidt G. Palivan C. Neshchadin D. Bertagnolli H. Feth M. Schweiger A. Mitrikas G. Harmer J. J. Am. Chem. Soc.  2003,  125:  6222 

5 Harmata M. Chemtracts: Org. Chem.  2003,  16:  660 

6 Review: Haake M. In Topics in Sulfur Chemistry   Senning A. Thieme; Stuttgart: 1976.  Vol. 1. p.185 

7 Diederich WE. Haake M. J. Org. Chem.  2003,  68:  3817 ; and references therein

8 To the best of our knowledge, there is only one single report on the synthesis of a non-racemic sulfodiimine, and in this case, the enantiomer ratio has not been determined: Christensen BW. Kjær A. J. Chem. Soc., Chem. Commun.  1975,  784 

9 Haake M. Fode H. Eichenauer B. Liebigs Ann. Chem.  1972,  759:  107 

10 Hackenberger CPR. Raabe G. Bolm C. Chem.-Eur. J.  2004,  10:  2942 ; and references therein

For reviews on coupling reagents, see:

11a Han S.-Y. Kim Y.-A. Tetrahedron  2004,  60:  2447 

11b Klausner YS. Bodansky M. Synthesis  1972,  453 

12

In this case, the meso-product resulting from an epimerization would possess two diastereotopic methyl groups. Those would be in rather different chemical and electronic environments and, therefore, two different chemical shifts would be likely to occur in the ¹H NMR spectrum.