Cyclopropenone carbonyl oxide

Bernhardsson and coworkers have recently used CASPT2 calculations (electron-correlation correction to the CAS wave function) to model carbonyl oxides in solution. Solvation effects in acetonitrile solvent also suggest that the zwitterionic form would be favored with an elongation of the 0—0 bond length and a decrease in the C—O bond. Ab initio calculations have been recently reported for monofluorocarbonyl oxide , diflu-orocarbonyl oxide , methylcarbonyl oxide and cyclopropenone carbonyl oxide. In the recent literature the idea that carbonyl oxide can be an important source of OH radicals has also been presented. ... 

Since the dipole moments of cyclopropenones are enlarged with respect to simple ketones and compare to other polar systems, e.g. trimethylamine oxide in Table 4, there seems to be evidence for considerable charge separation in the carbonyl group, which was expressed in terms of a cyclopropenium oxide contribution to the ground state. 

Tetracyano ethylene oxide, however, which represents a potential 1,3-dipole of the carbonyl ylide type, reacts with diphenyl cyclopropenone to give a cycloadduct of probable structure 415/417263, which may arise from insertion into the cyclopropenone C1(2)/C3 bond. 

Oxidative addition of a C(carbonyl)-C bond has been observed directly with highly strained unsaturated ketones. When a platinum(O) ethylene complex was treated with a cyclopropenone, the ethylene ligand was replaced with the olefin moiety of the cyclopropenone to produce a platinum T -cyclopropenone complex. The platinum center then inserted site-selectively into the sterically less-crowded C(carbonyl)-C bond of the cyclopropenone to form a platinacyclobutenone (Scheme 1.12) [20]. 

Full details of the preparation of cyclopropenone have appeared in Organic Syntheses Under basic conditions, diphenylcyclopropenone reacts with mal-ononitrile and ethyl cyanoformate at the carbonyl group to give the butadienes (14)/ The key step in the oxidation of cyclopropenones (15) by peracid... 

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