Following earlier room-temperature studies, gaseous mixtures of methyl cyclobutyl ketone (MCK) diluted in argon have been photolyzed at temperatures up to 205Β°C. Experiments have been carried out at a variety of pressures (up to ca. 2 atm) at wavelengths of 313 nm (steady state conditions) and 308 n
The photolysis of 3,3-dimethylbutan-2-one (methyl t-butyl ketone) and the decomposition of the acetyl radical
β Scribed by H. M. Frey; I. C. Vinall
- Publisher
- John Wiley and Sons
- Year
- 1973
- Tongue
- English
- Weight
- 776 KB
- Volume
- 5
- Category
- Article
- ISSN
- 0538-8066
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β¦ Synopsis
Abstract
The photolysis of 3,3βdimethylbutanβ2βone (MTBK) has been studied in the gas phase at 408 and 326 K, mainly with light of 313 nm wavelength. At the higher temperature, the major products were methane, ethane, isobutane, isobutene, neopentane, tetramethylbutane, and carbon monoxide. At 326 K, in addition to these products, appreciable quantities of acetaldehyde, acetone, and biacetyl were detected. Quantum yields were determined using acetone and pentanβ3βone as actinometers. A conventional mechanism is able to explain most of the experimental data. At 326 K, the results may be interpreted to yield a value for the rate constant for decomposition of the acetyl radical. Some theoretical calculations are reported on the acetyl radical decomposition and some earlier experimental work on this radical reevaluated.
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