A Convenient Unsymmetric Functionalization of Diaza-21-Crown-7

Abstract

The synthesis of N-Boc-diaza-21-crown-7 (4) is described. Bis-Boc-protected 1,8-diamino-3,6-dioxaoctane (2) was treated with 1,11-diiodo-3,6,9-trioxaundecane to form N,N′-bis-Boc-diaza-21-crown-7 (3) in moderate yield. Treatment of the bis-Boc-protected crown with trifluoroacetic acid resulted in isolation of the desired mono-N-Boc-diaza-21-crown-7 (4) with none of the expected diaza-21-crown-7.

Key words

diaza-21-crown-7 - unsymmetrical functionalization - Boc group

References

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1

Present address: Department of Chemistry, University of Florida, P. O. Box 117200, Gainesville, FL 32611-7200.