Synthesis of new dibenzo nitrogen‐oxygen donor macrocycles containing two amide groups

Abstract

Four new nitrogen‐oxygen, dibenzo macrocyclic ligands containing two amide groups have been prepared by combining a dibenzo‐containing diamidodialdehyde with an appropriate diamine followed by reduction of the intermediate bis Schiff‐base. The starting dibenzo‐containing diamidodialdehyde was prepared by treating 2 equivalents of salicylaldehyde with a bis(α‐chloroamide).

Efficient synthesis of novel bis(dihydropyrano[2,3c]pyrazoles), bis(4H-chromenes) and bis(dihydropyrano[3,2-c]chromenes) with amide functionality

“…The TLC of the reaction mixtures indicates the presence of a mixture of products which could unfortunately not be separated or identified (Scheme 1). In the second approach, the bis-aldehyde 12a containing an amide linkage was prepared following the reported methods described by our group 8,[38][39][40][41] via the reaction of the potassium salt of the salicylaldehyde 11 with the corresponding bis(2-chloroacetamide) 4a in boiling DMF (Scheme 2).…”

Interaction of Co(ii), Ni(ii) and Cu(ii) with dibenzo-substituted macrocyclic ligands incorporating both symmetrically and unsymmetrically arranged N, O and S donors

“…The preparations in each case involved a double Schiff-base condensation between the appropriate linear diamine derivative and the corresponding unsymmetrical dialdehyde precursor, followed by in situ reduction of the resulting diimine with sodium borohydride. Isolation of the diimine (or its isomeric 1,3-diazacyclopentane) 21 intermediate prior to reduction was found to be unnecessary. The microanalytical, mass spectra, 1 H and 13 C NMR results were in each case in accord with formation of the expected product.…”

Synthesis of Azacrown Macrocycles and Related Compounds by a Crablike Cyclization Method: A Short Review

“…The bis(benzaldehyde) was then cyclized with a diamine followed by reduction of the cyclic bis(imine) (Scheme ). It was found that potassium tert -butoxide gave much better yields in the first step of this synthesis than sodium carbonate 22

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“…It was found that potassium tert-butoxide gave much better yields in the first step of this synthesis than sodium carbonate. 35 Other applications of the crablike cyclization reaction are less known. A bis(chloroacetyl) derivative was obtained in 83% yield from diaza-12-crown-4 and chloroacetic anhydride.…”