- Tytuł:
-
Strukturalne konsekwencje wiązania wodorowego
Strustural consequences of the h-bonding - Autorzy:
-
Krygowski, T.M.
Szatyłowicz, H. - Powiązania:
- https://bibliotekanauki.pl/articles/171995.pdf
- Data publikacji:
- 2011
- Wydawca:
- Polskie Towarzystwo Chemiczne
- Tematy:
-
wiązanie wodorowe
podstawione fenole
podstawione aniliny
aromatyczność
AIM
NBO
H-bond
substituted phenols
substituted anilines
aromaticity
atoms in molecules
natural bond orbital
NBO analysis - Opis:
- Hydrogen bonding belongs to the most important chemical interactions in life and geochemical processes as well as in technologies, that is documented in many review articles [1-10], monographs [11-17] and numerous publications. Figure 1 presents how "popular" are studies concerning hydrogen bonds (the term H-bond/bonding/bonded in a title, key-words or in abstract) in the last decade. First information about H-bond formation appeared at the end of XIX and a few other at beginning of XX centuries [19-24]. Most common definition of H-bonding stems from Pauling [27], whereas the newest IUPAC definition was published very recently [26]. Most frequently H-bonding is experimentally described by geometry parameters [28, 32] - results of X-ray and neutron diffraction measurements, but NMR and IR/Raman spectroscopies are also in frequent use. Characteristic of interactions by H-bonding is usually discussed in terms of energies [29-31], with use of various quantum chemical theories [54-57] and applications of various models as AIM [35, 41, 42, 45-48] and NBO [43, 44] which allowed to formulate detailed criteria for H-bond characteristics [35, 48]. H-bonds are classified as strong, mostly covalent in nature [7, 29, 34], partly covalent of medium strength [35] and weak ones, usually non-covalent [7, 29, 34, 35]. Theoretical studies of H-bonding mainly concern equilibrium systems, however simulation of H-bonded complexes with controlled and gradually changing strength of interactions [61-71] are also performed. The latter is main source of data referring to effect of H-bonding on structural properties: changes in the region of interactions, short and long-distance consequences of H-bonding. Application of the model [61] based on approaching hydrofluoric acid to the basic center of a molecule and fluoride to the acidic one, (Schemes 2 and 3) allows to study changes in molecular structure of para-substituted derivatives of phenol and phenolate [62, 64] in function of dB…H, or other geometric parameter of H-bond strength (Fig. 2). It is also shown that CO bond lengths in these complexes is monotonically related to H-bond formation energy and deformation energy due to H-bond formation [65]. Alike studies carried out for para-substituted derivatives of aniline and its protonated and deprotonated forms [77, 78, 81] give similar picture (Fig. 3). AIM studies of anilines [77, 78] lead to an excellent dependence of logarithm of electron density in the bond critical point and geometric parameter of H-bond strength, dB…H presented in Figure 4. Substituents and H-bond formation affect dramatically geometry of amine group [66] in H-bonded complexes of aniline as shown by changes of pyramidalization of bonds in amine group (Fig. 5). Some short- and long-distance structural consequences of H-bonding are shown by means of changes in ipso angle (for amine group) in the ring and ipso-ortho CC bond lengths (Fig. 6). Moreover, the mutual interrelations are in line with the Bent-Walsh rule [84, 86]. Changes of the strength of H-bonds in complexes of p-substituted aniline and its protonated and deprotonated derivative are dramatically reflected by aromaticity of the ring66 estimated by use of HOMA index [87, 88] (Fig. 7), where strength of H-bonding is approximated by CN bond lengths. Scheme 4 presents application of the SESE [91] (Substituent Effect Stabilization Energy) for description in an energetic scale joint substituent and H-bond formation effects.
- Źródło:
-
Wiadomości Chemiczne; 2011, 65, 11-12; 953-974
0043-5104
2300-0295 - Pojawia się w:
- Wiadomości Chemiczne
- Dostawca treści:
- Biblioteka Nauki
Artykuł