Andrés Guerrero

  • Citations Per Year
Learn More
The acidity-enhancing effect of BH(3) in gas-phase phosphineboranes compared to the corresponding free phosphines is enormous, between 13 and 18 orders of magnitude in terms of ionization constants. Thus, the enhancement of the acidity of protic acids by Lewis acids usually observed in solution is also observed in the gas phase. For example, the gas-phase(More)
We show that the radical cations of adamantane (C(10)H(16)(*+), 1H(*+)) and perdeuteroadamantane (C(10)D(16)(*+), 1D(*+)) are stable species in the gas phase. The radical cation of adamantylideneadamantane (C(20)H(28)(*+), 2H(*+)) is also stable (as in solution). By using the natural (13)C abundances of the ions, we determine the rate constants for the(More)
We have carried out a study of the energetics, structural, and physical properties of o-, m-, and p-hydroxybenzophenone neutral molecules, C(13)H(10)O(2), and their corresponding anions. In particular, the standard enthalpies of formation in the gas phase at 298.15 K for all of these species were determined. A reliable experimental estimation of the(More)
Intermolecular and intramolecular halogen···π interactions in benzylic halides (Ph-CR2-X; X = F, Cl, Br and I) derived from 7-phenylnorbornane were investigated. The imposed geometry of the 7-arylnorbornane moiety prevents the participation of intramolecular attractive interactions between the σ-hole region of the halogen atom and the π electrons of the(More)
We have studied the energetics and structural properties of trans-cinnamic acid (CA), o-, m-, and p-coumaric acids (2-, 3-, and 4-hydroxycinnamic acids), caffeic acid (3,4-dihydroxycinnamic acid), ferulic acid (4-hydroxy-3-methoxycinnamic acid), iso-ferulic acid (3-hydroxy-4-methoxycinnamic acid), and sinapic acid (3,5-dimethoxy-4-hydroxycinnamic acid). The(More)
Laparoscopic colectomy has developed into a viable alternative to colon surgery. This paper presents an overview of the development and current status of laparoscopic surgery of the colon with a brief review of the evidence of efficacy of laparoscopic surgery in cancer management. The experience with laparoscopic surgery of the colon at a tertiary hospital(More)
The dissociation dynamics of Sn(CH(3))(4)(+), Sn(CH(3))(3)Cl(+), and Sn(CH(3))(3)Br(+) were investigated by threshold photoelectron photoion spectrometry using an electron imaging apparatus (iPEPICO) at the Swiss Light Source. The tetramethyltin ion was found to dissociate via Sn(CH(3))(4)(+) → Sn(CH(3))(3)(+) + CH(3) → Sn(CH(3))(2)(+) + 2CH(3), while the(More)
The applicability of the extended kinetic method (EKM) to determine the gas phase acidities (GA) of different deprotonable groups within the same molecule was tested by measuring the acidities of cinnamic, coumaric, and caffeic acids. These molecules differ not only in the number of acidic groups but in their nature, intramolecular distances, and calculated(More)
Hydrogen-bonding interactions involving 2-(trifluoromethyl)-1,1,1,3,3,3-hexafluoropropane (1H) and 1(-) have been quantitatively studied by means of Fourier transform ion cyclotron resonance spectrometry. The existence of the species (1HCl)(-) and (1H1)(-) was demonstrated, and their thermodynamic stabilities were determined experimentally and(More)
  • 1