Microwave-assisted aliphatic fluorine-chlorine exchange using triethylamine trihydrofluoride (TREAT-HF)

Tetrahedron Letters

Volumn 50, Issue 26, 2009, Pages 3665-3668

  Kremsner, Jennifer M ^a   Rack, Michael ^b   Pilger, Christian ^b   Oliver Kappe, C ^a  

^a UNIVERSITY OF GRAZ   (Austria)

^b BASF SE   (Germany)

Author keywords

Fluorination; gem Difluoride; Microwave irradiation; Pyrazole; Silicon carbide

Indexed keywords

CHLORINE; FLUORIDE; FLUORINE; SILICON CARBIDE; TRIETHYLAMINE;

ARTICLE; CHEMICAL REACTION; FLUORINATION; MASS FRAGMENTOGRAPHY; MICROWAVE RADIATION; TEMPERATURE;

EID: 65649094517     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2009.03.103     Document Type: Article

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34. CAUTION! Corrosion of microwave vials during usage represents a serious safety risk as the pressure rating of the heavy-walled vials (20 bar) will not be maintained. Prolonged exposure of TREAT-HF at high temperatures and pressures (e.g., ca. 10 bar at 250 °C) or repeated vial usage must therefore be strictly avoided.
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42. The fluorination was performed on an unseparable mixture of the 3-dichloromethyl pyrazole 14 and its 5-dichloromethyl isomer. See Supplementary data for more details.