Imidic acids trimerization

Methyl isocyanate and all isocyanic acid esters are an interesting and highly reactive class of organic compounds, since the isocyanate group (-NC0) reacts readily with a wide variety of compounds as well as with itself to form dimers, trimers, ureas, and carbodi-imides. Methyl isocyanate (MIC) is an intermediate in the preparation of carbamate pesticides and conceivably could be applied to the production of special heterocyclic polymers and derivatives. 

The purpose of the present investigation was to study the trimerization of aromatic nitriles under the conventional resin/fiber composite fabrication conditions using p-toluenesulfonic acid as a catalyst. Trimerization parameters investigated included reaction temperature, pressure, time, and concentration of catalyst. The influence of the nature of aromatic nitriles on trimerization was also studied. Also presented are preliminary results on the use of the catalytic trimerization of the nitrile-terminated imide oligomers to fabricate graphite fiber reinforced composites. 

On the other hand, when two glutamic acids were attached to the dye molecules, the possibility arose of connecting two or more nanoparticles with rylene dyes. Thus, the designed TDI 38 with two dicarboxylic acid anchors at the imide nitrogen atoms was synthesized by the same procedure as described above. The dianhydride 43 was obtained by complete saponification of TDI 42 [7]. Further imidization of 43 and p-glutamic acid afforded TDI 38 [58] (Scheme 10). The complexation between TDI 38 and QDs led to the formation of QD dimers and trimers, for which energy transfer from the QDs to the TDI bridge was observed. 

It was reported that a dimeric Zn +-cyclen 4 (Zn2L ) + binds to barbital, a dimide compound, to form the 1 1 complex 10 [(Zn2L )-(Bar )] + (Scheme 3.5). " A trimeric (Zn -cyclen) complex having a 1,3,5-trimethylbenzene core 11 (tris(Zn +-cyclen), (Zn3L ) +) was synthesized for use in recognizing cyanuric acid (CA), a tri-imide compound for the formation of a 1 1 complex 12 (Scheme 3.5). 

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