SOLID AND SOLUTION-PHASE ORGANIC SYNTHESES OF OLIGOMERIC THIOUREAS

In order to study supramolecular architectures built from unnatural ol igomeric and polymeric structures, one must first have an efficient sy nthetic strategy to produce them. Oligomers built from thiourea groups should form complex secondary and tertiary structures due to the hydr ogen-bonding capabilities of the thioureas. Herein, both solution and solid phase synthetic procedures that yield oligomeric thioureas are d escribed. They rely on the coupling of an isothiocyanate with an amine to produce the thiourea linkage. The monomers are derived from simple diamines. Higher yields are achieved using the solid phase method due to the ability to easily monitor the extent of reaction, to use a lar ge excess of reagent, and to perform purification after cleavage from the solid support. A variety of oligomers are given as examples. The p rocedure is quite general, should be easily extended to complex monome rs, and will allow the investigation of intramolecular and intermolecu lar interactions.