AAAA-DDDD Quadruple Hydrogen-Bond Arrays Featuring NH center dot center dot center dot N and CH center dot center dot center dot N Hydrogen Bonds
MetadataShow full item record
The X-ray crystal structure of a previously reported extremely strong quadruple NH center dot center dot center dot N AAAA-DDDD hydrogen-bond array [5.4] (K-a 1.5 x 10(6) M-1 in CH3CN; K-a > 3 x 10(12) M-1 in CH2Cl2) features four short linear hydrogen bonds. Changing the two benzimidazole groups of the DDDD unit to triazole groups replaces two of the NH center dot center dot center dot N hydrogen bonds with CH center dot center dot center dot N interactions (complex [5.6]), but only reduces the association constant in CH3CN by 2 orders of magnitude (K-a = 2.6 x 10(4) M-1 in CH3CN; K-a > 1 x 10(7) M-1 in CH2Cl2). Related complexes without the triazole groups range in K-a from 18 to 270 M-1 in CH3CN, suggesting that the CH center dot center dot center dot N interactions can be considered part of a strong AAAA-DDDD quadruple hydrogen-bonding array. The NH center dot center dot center dot N/CH center dot center dot center dot N AAAA-DDDD motif can be repeatedly switched "on" and "off" in CDCl3 through successive additions of acid and base.
Leigh , D A , Robertson , C C , Slawin , A M Z & Thomson , P I T 2013 , ' AAAA-DDDD Quadruple Hydrogen-Bond Arrays Featuring NH center dot center dot center dot N and CH center dot center dot center dot N Hydrogen Bonds ' Journal of the American Chemical Society , vol 135 , no. 26 , pp. 9939-9943 . DOI: 10.1021/ja404504m
Journal of the American Chemical Society
© 2013. American Chemical Society. This is an article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) International license, which permits others to distribute, remix, adapt and build upon this work, for noncommercial use, provided the original work is properly cited
This work is supported by funding from the EPSRC UK.
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Showing items related by title, author, creator and subject.
Knight, Fergus Ross; Fuller, Amy; Buehl, Michael; Slawin, Alexandra Martha Zoya; Woollins, J Derek (2010-07-05) - Journal articleA series of eight 1-halo-8-(alkylchalcogeno)naphthalene derivatives ( 1 – 8 ; halogen=Br, I; alkylchalcogen=SEt, SPh, SePh, TePh) containing a halogen and a chalcogen atom occupying the peri positions have been prepared ...
Would you like to add a weight after this blood pressure, doctor? Discovery of potentially actionable associations between the provision of multiple screens in primary care Kalia, Sumeet; Greiver, Michelle; Zhao, Xu; Meaney, Christopher; Moineddin, Rahim; Aliarzadeh, Babak; Grunfeld, Eva; Sullivan, Frank (2018-01-19) - Journal articleRationale, aims, and objective: Guidelines recommend screening for risk factors associated with chronic diseases but current electronic prompts have limited effects. Our objective was to discover and rank associations ...
Welch, Brett (University of St Andrews, 2014-01-30) - ThesisThe purpose of this project is to argue that we possess a minimal self. It will demonstrate that minimal selfhood arrives early in our development and continues to remain and influence us throughout our entire life. There ...