18206-43-4Relevant articles and documents
Photocatalytic Decarboxylative Coupling of Aliphatic N-hydroxyphthalimide Esters with Polyfluoroaryl Nucleophiles
Hu, Xile,Lavrencic, Lara,Mao, Runze,Yi, Xiangli
supporting information, p. 23557 - 23563 (2021/09/30)
Polyfluoroarenes are an important class of compounds in medical and material chemistry. The synthesis of alkylated polyfluoroarenes remains challenging. Here we describe a decarboxylative coupling reaction of N-hydroxyphthalimide esters of aliphatic carboxylic acids with polyfluoroaryl zinc reagents (Zn-ArF) via synergetic photoredox and copper catalysis. This method readily converts primary and secondary alkyl carboxylic acids into the corresponding polyfluoroaryl compounds, which could have a wide range of F-content (2F-5F) and variable F-substitution patterns on the aryl groups. Broad scope and good functional group compatibility were achieved, including on substrates derived from natural products and pharmaceuticals. Mechanistic study revealed that a [Cu-(ArF)2] species could be responsible for the transfer of polyfluoroaryl groups to the alkyl radicals.
COPPER-CATALYZED C-H BOND ARYLATION
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Page/Page column 20, (2009/04/24)
The present invention is a one-step method for efficiently converting carbon-hydrogen bonds into carbon-carbon bonds using a combination of aryl halides, a substrate, and a copper salt as catalyst. This method allows faster introduction of complex molecular entities, a process that would otherwise require many more steps. This invention is particularly relevant for the organic synthesis of complex molecules such as, but not limited to, pharmacophores and explosives.
Photochemical reactions of [Re(η5-C5R5)(CO)3] (R = H or Me) with partially fluorinated benzenes: C-H and C-F activation
Godoy, Fernando,Higgitt, Catherine L.,Klahn, A. Hugo,Oelckers, Beatriz,Parsons, Simon,Perutz, Robin N.
, p. 2039 - 2047 (2007/10/03)
UV Irradiation of [Re(η5-C5R5)(CO)3] (R = Me or H) in the presence of C6F5H or 1,2,4,5-C6F4H2 effected intramolecular C-H activation, generating the hydrido complexes trans-[Re(η5-C5R5)(CO)2(Ar) FH] [(Ar)F = C6F5 or 2,3,5,6-C6F4H] as the principal photochemical products. The identities of the hydrido complexes were confirmed by independent thermal syntheses. The photoreaction of [Re(η5-C5Me5)(CO)3] with C6F5H also generated the fulvene complex [Re(η6-C5Me4CH2)(CO) 2(C6F5)] 2a and two bis(aryl) derivatives: cis-[Re(η5-C5Me5)(CO)2(C 6F5)2] 3a and [Re(η5-C5Me5)(CO)2(C 6F5)(2,3,5,6-C6F4H)] 4a in low yield. Complex 2a results from an intramolecular C-H activation, while 3a and 4a derive from a C-H and a C-F activation of a second molecule of pentafluorobenzene, respectively. The origin of the minor products was elucidated by showing that UV irradiation of [Re(η5-C5Me5)(CO)2-(C 6F5)H] in C6F5H produces 2a, 3a and 4a, while photolysis of 2a produces only 3a. The reaction of [Re(η5-C5Me5)-(CO)3] with 1,2,4,5-C6F4H2 gave analogues 2b and 4b as minor products. The photoreaction of [Re(η5-C5H5)(CO)3] in C6F5H or 1,2,4,5-C6F4H2 generated bis(aryl) compounds and the unusual binuclear complexes [Re2(η5-C5H5)(μ-η 1:η5-C5H4)(CO) 4(Ar)F] as the minor products. The binuclear complex with (Ar)F = 2,3,5,6-C6F4H has been characterized by X-ray crystallography. The Re-Re bond [3.0258(7) A] is close to collinear with the Re-C (aryl) bond. One {Re(CO)2} unit is twisted by about 73.0° with respect to the other.
