Details

Autor(en) / Beteiligte

• Thomas, Javix
• Liu, Xunchen
• Jäger, Wolfgang
• Xu, Yunjie

Titel

Unusual H-Bond Topology and Bifurcated H-bonds in the 2-Fluoroethanol Trimer

Ist Teil von

• Angewandte Chemie International Edition, 2015-09, Vol.54 (40), p.11711-11715

Auflage

International ed. in English

Ort / Verlag

Weinheim: WILEY-VCH Verlag

Erscheinungsjahr

2015

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• By using a combination of rotational spectroscopy and ab initio calculations, an unusual H‐bond topology was revealed for the 2‐fluoroethanol trimer. The trimer exhibits a strong heterochiral preference and adopts an open OH⋅⋅⋅OH H‐bond topology while utilizing two types of bifurcated H‐bonds involving organic fluorine. This is in stark contrast to the cyclic OH⋅⋅⋅OH H‐bond topology adopted by trimers of water and other simple alcohols. The strengths of different H‐bonds in the trimer were analyzed by using the quantum theory of atoms in molecules. The study showcases a remarkable example of a chirality‐induced switch in H‐bond topology in a simple transient chiral fluoroalcohol. It provides important insight into the H‐bond topologies of small fluoroalcohol aggregates, which are proposed to play a key role in protein folding and in enantioselective reactions and separations where fluoroalcohols serve as a (co)solvent. The unexpected: The trimer of 2‐fluoroethanol demonstrates a striking case of chirality‐induced H‐bond topology switching. It strongly favors a heterochiral arrangement stabilized by both normal and bifurcated H‐bonds, rather than the common binding topology with a cyclic OH⋅⋅⋅OH bonded ring that is adopted by trimers of water and other related alcohol molecules. The role of transient chirality and the strength of the bifurcated H‐bonds were investigated.