Syntheses and characterisation of diurea molecular tweesors for the recognition of anion

• R. C JAGESSAR ^[1]
  1. [1] University of Guyana

     University of Guyana

     Guyana

     
• Localización: Journal of the Chilean Chemical Society (Boletín de la Sociedad Chilena de Química), ISSN-e 0717-6309, ISSN 0366-1644, Vol. 58, Nº. 4, 2013, págs. 2222-2225
• Idioma: inglés
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• Resumen

  • Two novel urea anion receptors (11) and (12) were synthesized from building block 3,3' methylene diamine and was characterized via the techniques of ¹H NMR, 13CNMR, DEPT- 135 ¹H-¹H COSY, HMQC and HMBC spectroscopy. The ¹H NMR profile of both compounds reveals diagnostic peaks. For compound (11), the urea NH protons resonate as two singlets downfield at 8.706 ppm and 8.635 ppm, whereas for compound (12) these two urea -NHCONH protons resonate together at 8.614 ppm. There seem to be no rotation of the structure on the NMR time scale as the bridged CH2 protons resonate as a singlet. The integration pattern for the aromatic hydrogens for both compounds is: 2: 4: 2: 4: 4, consistent with the structure. 13CNMR spectrums reveal fourteen signals for both structures in accordance with fourteen different types of carbon. Dept-135 indicates eight different CH protons. Preliminary anion binding studies via ¹HNMR spectroscopy revealed complexation with dicarboxylate anions in the highly competitive solvent, d6-DMSO.