49724-60-9Relevant academic research and scientific papers
An efficient procedure for the synthesis of crystalline aryldiazonium trifluoroacetates - Synthetic applications
Colas, Christophe,Goeldner, Maurice
, p. 1357 - 1366 (2007/10/03)
We have developed a very mild procedure for the synthesis of crystalline aryldiazonium trifluoroacetate salts in high yields under anhydrous conditions. Over thirty mono- or polyfunctional aniline derivatives have been diazotized by this method, including water- and acid-sensitive substrates. The o- and p-hydroxyaryldiazonium salts, derived from the corresponding anilines, could be deprotonated by treatment with K2CO3 to yield pure diazoquinones. NMR and UV/Vis spectra have been recorded for all the synthesized salts; the data are in good agreement with the rather limited published data and constitute a first extensive report of 13C-NMR chemical shifts in diazonium salts. An excellent linear relationship emerged between Brown's substituent constants S+(p) and the 13C(ipso) chemical shifts. The diazonium salts obtained proved to be much more soluble in organic solvents than their tetrafluoroborate counterparts. They were tested in Pd-mediated coupling reactions of various carbon-carbon double bonds, and were found to give good yields within short reaction times under very mild conditions. We believe that diazonium trifluoroacetates represent a very attractive alternative to diazonium tetrafluoroborates.
Development of a no-carrier-added method for 18F-labelling of aromatic compounds by fluorodediazonation
Knoechel, Arndt,Zwernemann, Olaf
, p. 325 - 336 (2007/10/03)
To improve the accessibility of [18F]arylfluorides a method is presented using the decomposition of aromatic diazonium salts in the presence of [18F]fluoride. Several p-toluidyldiazonium salts have been synthesized and decomposed in the presence of fluoride. The most useful salt, p-toluidyldiazomum-2,4,6-tri-isopropylbenzenesulfonate, has been used to investigate several parameters influencing the fluorination. No-carrier-added labelling with [18F]fluoride gave a radiochemical yield of 39% [18F]p-fluorotoluene in a total synthesis time of 78 minutes.
