Direct addition of fluorine to arylacetylenes

Controllable double CF2-insertion into sp2 C–Cu bond using TMSCF3: a facile access to tetrafluoroethylene-bridged structures

“…Current methods for the syntheses of tetrauoroethylenebridged structures are mainly based on (1) deoxouorination of 1,2-dicarbonyl compounds with SF 4 and DeoxoFluor; [9][10][11] (2) uorination of C-C triple bonds using F 2 ; [12][13][14] (3) 1,2-difunctionalization of tetrauoroethylene (TFE); [15][16][17][18][19][20][21][22][23] (4) diuoromethylene insertion using CF 2 Br 2 as the CF 2 source; 24,25 and (5) using RCF 2 CF 2 Br as the build block. 5 However, these methods suffer from several drawbacks such as (1) using toxic, highly reactive or hazardous reagents; (2) low functional group tolerance and/or (3) using explosive gaseous reagents or ozonedepleting substances (ODS).…”

Advances in the Synthesis and Application of Tetrafluoroethylene‐ and 1,1,2,2‐Tetrafluoroethyl‐Containing Compounds

“…Later work from McEwen reported only the formation of inseparable mixture of products by fluorination of acetylenes using diluted F 2 in CFCl 3 . In 2009, it was finally proven that the fluorination of acetylenes with diluted F 2 was possible (Table , entries 1 and 2) and that the presence of alcohol was essential for a clean reaction to occur.…”

“…Later work from McEwen reported only the formation of inseparable mixture of products by fluorination of acetylenes using diluted F 2 in CFCl 3 . [42] In 2009, it was finally proven that the fluorination of acetylenes with diluted F 2 was possible ( Table 2, entries 1 and 2) [43] and that the presence of alcohol was essential for a clean reaction to occur. 1 [43] Ph Ph 3-10 % F 2 in N 2 CFCl 3 /CHCl 3 : -78 -75 EtOH (4:5:1) 2 [43] Ph nPr 3-10 % F 2 in N 2 CFCl 3 /CHCl 3 : -78 -45 EtOH (4:5:1) 3 [44] Ph Ph XeF 2 (2), HF (1) CH 2 Cl 2 RT 6 64 4 [44] Ph nPr XeF 2 (2), HF (1) CH 2 Cl 2 RT 6 55 NO + BF 4 -(3), 5 [45] Ph Ph CH 2 Cl 2 RT 24 75 PPHF NO + BF 4 -(3), 6 [45] Ph Et CH 2 Cl 2 RT 24 39 PPHF 7 [46] Ph Ph IF (5) CFCl 3 , CHCl 3 -75 0.08 60…”

“…While the reaction generally proceeds well with diarylacetylenes, monoarylacetylenes form by‐products and make separation difficult and dialkylacetylenes form the desired product only in negligible amounts …”

Halogens

“…It has now been demonstrated that arylacetylenes can be converted to tetrafluoroethane derivatives using a dilute mixture of F 2 (3-10% in N 2 ) bubbled through a solution of the arylacetylene at À78 1C. 9 Diluted F 2 has also found application in the fluorination of acyclic and cyclic b-ketoesters in conjunction with a Lewis-acid catalyst and chiral ligand system with the goal of achieving enantioselective fluorination. 10 Moreover, the first quaternary nitride-fluoride to be reported, Ce 2 MnN 3 F 2Àd , has been synthesised via fluorination of the ternary nitride Ce 2 MnN 3 with 10% F 2 /N 2 at 95-115 1C.…”