Synthesis and characterization of 1-aza-4-oxa-7-thiacyclononane: A novel azacrown heterocycle

Abstract

The heterocycle 1-aza-4-oxa-7-thiacyclononane ([9]aneNOS, 5) was prepared from the intermediate N-p-toluenesulfonyl-1-aza-4-oxa-7-thiacyclononane (3) upon its deprotection via Na/Hg amalgam. The byproduct, N,N -bis-(ptolylsulfonyl)-1,13-diaza-7,16-dioxa-4,10-dithiacylododecane (4), was also isolated from the pot mixture of 3. Compound 5 was characterized by 1 H and 13 C NMR, and IR spectroscopy. Compounds 3 and 4 were characterized by 1 H and 13 C NMR, and IR spectroscopy, elemental analysis, and X-ray crystallography. The reaction of 5 with Ni(BF 4 ) 2 •6 H 2 O in methanol produced the sandwich complex ([9]aneNOS) 2 Ni(BF 4 ) 2 , 6, which was characterized by UV-visible and IR spectroscopy, elemental analysis, and X-ray crystallography.

Cyclononanes: The extensive chemistry of fundamentally simple ligands

“…Reaction of the ligand with Ni(BF 4 ) 2 .6H 2 O in methanol resulted in isolation of a purple solid characterised by X-ray crystallography [229]. The structure shows the metal ion in a distorted Potentiometric titration reveals that the ligand displays two pK a s, 9.59 and 5.32 [230].…”

“…For 1,2-bis-(1-aza-4,7-dithiacyclononylethane) potentiometric titration revealed two pK a s (6.53 and 6.00); with silver(I) ions the 1:1 complex was observed (log 10 K = 7.03) [202,211]. For The [9]aneNOS ligand was prepared by reaction of 2-p-tolylsulfonylamidoethanethiol and 2,2'-bis-p-tolylsulfonylethy ether in anhydrous DMF in the presence of caesium carbonate and subsequent detosylation of the product resulting in isolation of a colourless waxy solid in 76% yield (Scheme 1) [229]. The [9]aneNOS product displayed the expected six line 13…”