1072315-89-9Relevant articles and documents
The photodecomposition mechanism of tert-butyl-9-methylfluorene-9- percarboxylate: New insight from femtosecond IR spectroscopy
Reichardt, Christian,Schroeder, Joerg,Schwarzer, Dirk
, p. 5218 - 5224 (2008)
The ultrafast photodissociation of tert-butyl-9-methylfluorene-9- percarboxylate (TBFC) is studied by mid-infrared transient absorption spectroscopy after UV excitation at 266 nm. By means of 13C-labeled TBFC and additional DFT calculations transient IR bands in the fingerprint region were unambiguously assigned to the methylfluorenyl radical. The experiments show that the fragmentation is controlled by the S 1-lifetime of TBFC and, dependent on the solvent, within 0.8-2.1 ps leads to tert-butyloxy and methylfluorenyl radicals plus CO2via concerted bond breakage of the O-O and the fluorenyl-C(carbonyl) bond. In accordance, the CO2 quantum yield is determined to be unity.
14Carbon monoxide made simple - Novel approach to the generation, utilization, and scrubbing of 14carbon monoxide
Lindhardt, Anders T.,Simonssen, Roger,Taaning, Rolf H.,Gogsig, Thomas M.,Nilsson, Goeran N.,Stenhagen, Gunnar,Elmore, Charles S.,Skrydstrup, Troels
, p. 411 - 418 (2013/01/15)
A new method is reported for the efficient generation of 14CO that can be applied in transition metal-catalyzed carbonylation reactions. 14CO is produced by palladium-catalyzed decarbonylation of the stable acid chloride, 14COgen. When combined in a two-chamber system, the produced 14CO is incorporated into the target molecule with high efficiency. As the carbonylation chemistry is performed under mild conditions, this allows the 14C isotope to enter the synthesis into an advanced stage intermediate. The presented work includes two aminocarbonylations, one amidocarbonylation, and one carbonylative Suzuki-Miyaura coupling, all installing the 14C isotope in the final step of the synthesis. Finally, the identification of a highly efficient scrubber for the safe trapping and removal of any leftover 14CO is also disclosed. A new method for the simple generation of 14CO from a stable, easy to handle CO precursor 14COgen is presented. When combined with a two-chamber system, COware, the generated 14CO is successfully applied as the limiting reagent in any carbonylation reaction. Owing to the mild conditions, the desired labeled compounds could be obtained in the final synthetic step of a linear synthesis. Finally, the development of a highly efficient scrubber, capable of removing any remaining or excess 14CO, is presented. This method provides radiochemists with a complete solution for performing 14C-carbonylation chemistry. Copyright