20405-77-0Relevant articles and documents
Effect of Substituants on the Structure of the Vinyl Radical: Calculations and Experiments
Galli, Carlo,Guarnieri, Alessandra,Koch, Heinz,Mencarelli, Paolo,Rappoport, Zvi
, p. 4072 - 4077 (1997)
Literature reports indicate either a linear or a bent configuration for a-substituted vinyl radicals. In order to get a better insight into this structural question, calculations of the structure of some a-substituted vinyl radicals were conducted by the DFT approach [BLYP/6-31G(d,p) and B3LYP/ 6-311G(2d,2p)]. For vinyl radicals bearing α-type substituents (Me, SH, Cl, OH, F), the bent form is found to be the minimum energy structure; the inversion barrier of the E and Z forms is found to markedly increase as the electronegativity of the group increases. Vinyl radicals bearing π-type substituents (CH=CH2, CHO, CN, C6H5) are found to be linear. The effect of β-substituents is much lower, and the β-fluoro- and β-ethenylvinyl radicals, representative of α- and π-type substituents, are calculated to be bent. Comparison with other literature calculations, obtained by different methods for some similar vinylic radicals, supports our computational results. Experimental support was also sought, with particular regards to the inversion barrier of the bent radicals. Since a very high barrier is calculated for the α-fluorovinyl radical, its inversion rate could be slower than the "sampling" time of a proper chemical reaction. Indeed, the α-fluorovinyl radicals, generated from PhCH=C(F)Br by reaction with Bu3SnH/AIBN, retained the configuration of their precursors in the overall hydrodebromination process.
Decarboxylation and fluorination method for cinnamic acid and derivative thereof
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Paragraph 0050; 0051, (2017/02/24)
The invention discloses a decarboxylation and fluorination method for cinnamic acid and a derivative thereof. The method comprises the steps that the cinnamic acid or the derivative thereof reacts with 1-chloromethyl-4-fluorophenyl-1,4-diazabicyclo[2.2.2]octane bis(tetrafluoroboric acid) salt and an alkali compound in one pot, and the fluorination product (mainly a cis-form structure product) of the cinnamic acid or the derivative thereof is obtained. The method fills in the technical blank on the decarboxylation and fluorination method for carboxylic acid connected with SP2 hybridization carbon atoms in the prior art, and is easy to operate, short in process and high in product yield, and the industrial production requirement is met.
Copper-Mediated Radiofluorination of Arylstannanes with [18F]KF
Makaravage, Katarina J.,Brooks, Allen F.,Mossine, Andrew V.,Sanford, Melanie S.,Scott, Peter J. H.
supporting information, p. 5440 - 5443 (2016/11/04)
A copper-mediated nucleophilic radiofluorination of aryl- and vinylstannanes with [18F]KF is described. This method is fast, uses commercially available reagents, and is compatible with both electron-rich and electron-deficient arene substrates. This method has been applied to the manual synthesis of a variety of clinically relevant radiotracers including protected [18F]F-phenylalanine and [18F]F-DOPA. In addition, an automated synthesis of [18F]MPPF is demonstrated that delivers a clinically validated dose of 200 ± 20 mCi with a high specific activity of 2400 ± 900 Ci/mmol.
