Qualitative and quantitative measurements of hydrogen bond mediated scalar couplings in acyclic 1,3-diols.
نویسندگان
چکیده
[Structure: see text] OH...OH hydrogen bond mediated scalar couplings have been observed in acyclic syn- and anti-1,3-diols using a 2D 1H COSYLR NMR experiment and quantified with an uncertainty of +/-0.02 Hz with a selective-excitation spin-echo NMR experiment. A theoretical investigation confirmed the importance of the hydrogen bond in mediating the spin-spin coupling in these systems.
منابع مشابه
Nmr Detection of Intramolecular Oh/oh Hydrogen Bond Networks: an Approach Using Isotopic Perturbation and Hydrogen Bond Mediated Ohoh J-coupling
A series of conformationally restricted triol and tetrol systems containing intramolecular hydrogen bond arrays has been prepared and characterized by X-ray crystallography and NMR spectroscopy. NMR isotopic perturbation measurements in DMSO-d6 and CD2Cl2 reveal that this methodology can be used to detect the spatial proximity of up to four contiguous hydroxyl groups sharing a 1,3-, 1,4-, or 1,...
متن کاملAn Introduction to Hydrogen Bond Scalar Couplings
( ) ABSTRACT: The hydrogen bond H-bond has been recognized in science for more than 80 years as a concept to explain situations where a hydrogen atom is simultaneously binding to two other atoms. Due to the moderate energies necessary for their formation and rupture, hydrogen bonds play a fundamental role in many chemical reactions and most, if not all, interactions involving biological macromo...
متن کاملIsomerism and Hydrogen Bonding in the Cis-enol Forms of 1-(n-pyridyl)butane-1,3-diones: A Theoretical Study
Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(n-pyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the correspondin...
متن کاملQuantitative comparison of the hydrogen bond network of A-state and native ubiquitin by hydrogen bond scalar couplings.
The backbone hydrogen bond (H-bond) network of the partially folded A-state of ubiquitin (60% methanol, 40% water, pH 2) has been characterized quantitatively by (h3)J(NC)(') H-bond scalar couplings between the (15)N nuclei of amino acid H-bond donors and the (13)C carbonyl nuclei of the acceptors. Results on (h3)J(NC)(') couplings and the amide proton ((1)H(N)) chemical shifts for the A-state ...
متن کاملDirect assignment of the relative configuration in acyclic 1,3-diols by 1H NMR spectroscopy.
[chemical reaction: see text]. Using an operationally simple deuterium isotopic perturbation method, the relative configuration of 1,3-diols can be determined directly using 1H NMR spectroscopy. A comparison of the OH chemical shifts for OH/OH and OH/OD isotopomers provides a reliable assessment of the relative configuration of the diol; anti-1,3-diols within polyacetate and polypropionate fram...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Organic letters
دوره 8 23 شماره
صفحات -
تاریخ انتشار 2006