2-Trifluoromethoxyacetic acid – Synthesis and characterization

• OCF 3 -containing building blocks • electronic properties of trifluoromethoxy • fluorinated anions A straightforward and high-yield synthesis of 2-trifluoromethoxyacetic acid CF 3 OCH 2 C(O)OH starting from trifluoromethyl triflate CF 3 SO 2 OCF 3 is described. The trifluoromethoxide anion was generated from trifluoromethyl triflate and a fluoride source followed by a nucleophilic substitution reaction with the {OCF 3 } – ion to yield CF 3 OCH 2 C(O)OC 2 H 5 . The ester was converted into M{CF 3 OCH 2 CO 2 } (M = Na, K) and the acid CF 3 OCH 2 C(O)OH was obtained from the sodium salt and HCl. In addition, the silver(I) salt of the {CF 3 OCH 2 CO 2 } – anion was synthesized from CF 3 OCH 2 C(O)OH and silver(I) oxide. The study includes a new synthesis for the starting compound CF 3 SO 2 OCF 3 and a detailed description for the preparation of [N(CH 3 ) 4 ]{OCF 3 }. Furthermore, the crystal structures of CF 3 OCH 2 C(O)OH, CF 3 OCH 2 C(O)OC 2 H 5 , M{CF 3 OCH 2 CO 2 } (M = K, Ag), and [N(CH 3 ) 4 ]{OCF 3 } are reported.