69978-45-6Relevant academic research and scientific papers
FORMATION OF COMPLEXES BETWEEN AZA DERIVATIVES OF CROWN ETHERS AND PRIMARY ALKYLAMMONIUM SALTS. PART 8. 12-CROWN-4, 15-CROWN5, 21-CROWN-7, AND 24-CROWN-8 DERIVATIVES
Johnson, Martin R.,Jones, Nigel F.,Sutherland, Ian O.
, p. 1637 - 1644 (2007/10/02)
The monoaza-crown ethers (3), (4), and (5) and the diaza-crown ethers (6), (7), (10), and (11) form complexes with primary alkylammonium thiocyanates in organic solvents.The diaza-15-crown-5 system (11) forms well defined 1:1 complexes with the cis-, cis-stereochemistry shown in (16) but the diaza-24-crown-8-derivative (7) forms a 2:1 complex (G:H ratio) with benzylammonium thiocyanate having the cis,cis,trans,trans-stereochemistry (17a).The diaza-24-crown-6 derivative (10) forms weak 1:1 complexes which apparently adopt the double nesting conformation (18).
1,4,7-Trioxa-10-azacyclododecane and Some N-Substituted Derivatives; Synthesis and Cation Complexing
Calverley, Martin J.,Dale, Johannes
, p. 241 - 248 (2007/10/02)
Primary amines condense with 1,11-diiodo-3,6,9-trioxaundecane in acetonitrile solution containing dispersed Na2CO3 to give N-substituted derivatives of monoaza-12-crown-4, including several directly appended with an additional donor group.The unsubstituted azacrown and the N-methyl derivative were obtained from the N-benzyl derivative.The alkali cation complexing properties were studied by 13C NMR spectroscopy.It was found that the presence of an additional donor atom in the side-chain suppresses the formation of 2:1 in favour of 1:1 complexes.
