CENTRO DE QUIMICA INORGANICA "DR. PEDRO J. AYMONINO"
Unidad Ejecutora - UE
Preparation and properties of HCF2C(O)SeH and ClCF2C(O)SeH
JOVANNY A. GÓMEZ CASTAÑO; ROSANA M. ROMANO; HELMUT BECKERS; HELGE WILLNER; CARLOS O. DELLA VÉDOVA
AMER CHEMICAL SOC
Lugar: Washington; Año: 2012 vol. 51 p. 2608 - 2608
The novel selenocarboxylic acids difluoroselenoacetic, HCF2C(O)SeH, andchlorodifluoroselenoacetic, ClCF2C(O)SeH, were prepared treating thecorresponding carboxylic acids with Woollins´ reagent. The boiling points wereextrapolated from the vapor pressure curves, obtaining values of 364 and 359 Kfor HCF2C(O)SeH and ClCF2C(O)SeH, respectively. Both compounds areunstable at ambient temperatures, decomposing by dimerization of the moleculesand generation of H2Se. The hydrolysis results in the formation of the carboxylicacids and hydrogen selenide, while diselenide compounds are obtained byoxidation. The conformational preferences of these acids were studied byvibrational spectroscopy in combination with ab initio and DFT methods. The IRvapor-phase spectra, the Raman spectra of the net liquids, and the IR spectra ofthe Ar-matrix isolated compounds at two different temperatures were interpretedin terms of conformational equilibria. The most stable structure of both acidswere found to be syn-gauche in equilibrium with a second anti-syn form inHCF2C(O)SeH, and with other two conformers, anti-gauche and anti-syn, inClCF2C(O)SeH.