Synthesis and structural characterization of 3-thienyl alkyl imides

Five new thiophene imides having the structures C4H3SC(O)N(H)C(O)R (where R=Me, Et, Pr, t-Bu, ) and C4H3SCH2C(O)N(H)C(O)CH3 have been prepared. Control over the orientation of the carbonyl groups was achieved by the introduction of a bulky group in the terminal position of the side chain, and molecular modeling calculations indicated that the energy difference between the ct and tt conformations is small. The acidity of decreases from Me to t-Bu, and, although will not undergo oxidative polymerization, the introduction of a single spacer CH2 group allows to polymerize.