Preparation and synthetic applications of aryl tetraflates (ArOSO2CF2CF2H).
We have recently developed an improved synthetic route to 1,1,2,2-tetrafluoroethanesulfonic acid (HCF2CF2SO3H, TFESA) and explored the applications of this newly available superacid in catalysis. Low volatility, ease of handling, and a convenient 1H NMR handle make this acid an attractive alternative to triflic acid. TFESA can also be converted to several of its derivatives: anhydride, sulfonyl chloride, and sulfonyl fluoride, which provide a good entry point for the synthesis of aryl sulfonates. We prepared several aryl esters of 1,1,2,2-tetrafluoroethanesulfonic acid (aryl tetraflates) and showed that they can be used in a number of palladium-catalyzed coupling reactions (Suzuki, Heck, and Buchwald-Hartwig couplings). While the reactivity of tetraflates lies between that of triflates and chlorides, tetraflates appear to be more thermally stable. Additionally, the presence of a hydrogen atom in the tetraflate group facilitates monitoring of reactions and characterization of derivatives.
Rostovtsev
Vsevolod V
VV
DuPont Central Research and Development, Experimental Station, Wilmington, Delaware 19880, USA. vsevolod.rostovtsev@usa.dupont.com
Bryman
Lois M
LM
Junk
Christopher P
CP
Harmer
Mark A
MA
Carcani
Liane G
LG
D001190:Arylsulfonates / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D015394:Molecular Structure; D013237:Stereoisomerism; D013451:Sulfonic Acids / Q000737:chemistry*; D005466:Fluorocarbons
D001190:Arylsulfonates; D006845:Hydrocarbons, Fluorinated; D013451:Sulfonic Acids; C527440:1,1,2,2-tetrafluoroethanesulfonic acid; D005466:Fluorocarbons