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An investigation of the products from the reaction of ozone with aminodinitrotoluenes (ADNTs) provides information about the oxidation pathway. Studies conducted at low conversions of 2-and 4-ADNT show 2:1 ozone/ADNT stoichiometries, prompt formation of glyoxylic and pyruvic acids, and NO 2and NO 3 -(NO x ) ions. Reaction schemes to account for these results involve a 1,3-dipolar cycloaddition of ozone to selected double bonds of the aromatic ring, leading to ring cleavage. 15 N-Labeling experiments indicate that the amino function is not involved in the initial ozone oxidation and eventually is incorporated into pyruvamide (2-ADNT) and oxamic acid (4-ADNT) before being oxidized to nitrate.

A series of potassium complexes bearing monoanionic tetradentate amino-phenolate ligands, [LK] (L = {(2-R)CHCHN[(CH)R]CH(4-R-6-R)CHO-}, R = NMe, R = NEt, R = CPh, R = Me (1); R = R = NEt, R = CPh, R = Me (2); R = NMe, R = NEt, R = R = cumyl (4); R = R = OMe, R = Bu, R = Me (6); L = (2-NMe)CHCHN[[CH-(S)-1-butylpyrrolidinyl]CH(4-Me-6-CPh)CHO-] (3)), have been synthesized via reactions of KN(SiMe) and 1 equiv. of the corresponding aminophenols. The solid-state structures of typical complexes 4 and 6 are determined via X-ray diffraction studies, which reveal the dinuclear nature of these complexes. By contrast, DOSY measurements of 1, 4 and 6 suggest that these complexes are monomeric in solution. It is noteworthy that the coordination chemistry of these potassium complexes is versatile, which is closely related to the nature of the ortho-substituent of the phenolate ring, as indicated by the results of the corresponding spectroscopic studies. In the presence of PrOH, 1-4 and 6 could initiate the polymerization of 500 equiv. of rac-lactide to achieve high monomer conversions within several minutes but afford atactic PLAs with slightly isotactic-enriched microstructures (P = 0.58-0.60). Experimental results also demonstrated that a bulky trityl substituent at the ortho-position of the phenolate ring of the ligand framework is beneficial for the enhancement of the activities of these potassium complexes.