OXIDATIVE TRANSFORMATIONS OF 1-NITROPYRENE UNDER SIMULATED ENVIRONMENTAL-CONDITIONS

The oxidation of 1-nitropyrene (1-NP), adsorbed on silica gel, with di methyldioxirane (DMD) leads to the formation of 1-nitropyrene 4,5-oxid e and 1-nitropyrene 9,10-oxide in a ratio of 74/26 (4,5-oxide/9,10-oxi de). When the adsorbed 1-NP is exposed to the products of the gasphase reaction of tetramethylethylene (TME) with ozone at -40 degrees C, th e same oxides are produced in a ratio of 72/28. The fact that the rati o of the oxides is essentially the same in these two different types o f experiments is highly significant. We have speculated that the gas-p hase ozonolysis of TME produces an energy-rich form of the carbonyl ox ide, acetone oxide. Some of this carbonyl oxide may cyclize to the iso meric DMD which, we propose, is responsible for oxide formation in the TME/ozone experiment. This proposal is supported by the observation t hat using ozone alone to oxidize 1-NP does not lead to oxide formation . Thus the oxidant responsible for oxide formation in the TME/ozone ex periment must be produced in the ozonolysis. We suggest that this oxid ant is DMD.