Long-range ?-type hydrogen bond in the dimers CH2O?HF, CH2O?H2O, and CH2O?NH3

2005 ◽  
Vol 103 (3) ◽  
pp. 299-307 ◽  
Author(s):  
Ruiyan Li ◽  
Zhiru Li ◽  
Di Wu ◽  
Xiyun Hao ◽  
Rujiao Li ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Long Range ◽  
Range Type ◽  
Type Hydrogen Bond

Long-range ?-type hydrogen bond in dimers CH2?HF, CH2O?H2O, and CH2O?NH3

2005 ◽  
Vol 103 (2) ◽  
pp. 157-166 ◽  
Author(s):  
Rui Yan Li ◽  
Zhi Ru Li ◽  
Di Wu ◽  
Xi Yun Hao ◽  
Ru Jiao Li ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Long Range ◽  
Range Type ◽  
Type Hydrogen Bond

Long Range π-Type Hydrogen Bond in the Dimers (HF)2, (H2O)2, and H2O−HF

2001 ◽  
Vol 105 (7) ◽  
pp. 1163-1168 ◽  
Author(s):  
Li Zhi-Ru ◽  
Wu Di ◽  
Li Ze-Sheng ◽  
Huang Xu-Ri ◽  
Fu-Ming Tao ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Long Range ◽  
Type Hydrogen Bond

Left-Handed Helix of Three-Membered Ring Amino Acid Homopeptide Interrupted by an N–H···Ethereal O-Type Hydrogen Bond

2018 ◽  
Vol 20 (24) ◽  
pp. 7830-7834 ◽  
Author(s):  
Yurie Koba ◽  
Atsushi Ueda ◽  
Makoto Oba ◽  
Mitsunobu Doi ◽  
Takuma Kato ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Amino Acid ◽  
Membered Ring ◽  
Left Handed ◽  
Type Hydrogen Bond

Short and long range contributions to the inductive effect in π electron systems

1966 ◽  
Vol 291 (1425) ◽  
pp. 224-234 ◽  
Keyword(s):  
Long Range ◽  
Field Effect ◽  
Short Range ◽  
Inductive Effect ◽  
Electron Systems ◽  
Methyl Group ◽  
Range Type ◽  
Coulomb Type ◽  
Exchange Repulsion ◽  
Coulomb Attraction

It is shown that the inductive effect of a substituent can have contributions of both exchange and Coulomb type, but that the exchange terms can be treated empirically as though they arise from a short-range field effect. Calculations of the exchange terms for the halogens and the methyl group are in accord with the empirical values of inductive parameters deduced from spectroscopy. Evidence is given that for a methyl group the inductive perturbation is almost entirely of short range type and is probably dominated by the exchange terms but for a chloro substituent both the short range exchange repulsion and the long range Coulomb attraction are important.

Mechanisms of long-range 13C, 13C spin–spin coupling in thioanisole and its derivatives. Conformational applications

1988 ◽  
Vol 66 (5) ◽  
pp. 1229-1238 ◽  
Author(s):  
Ted Schaefer ◽  
Glenn H. Penner
Keyword(s):  
Hydrogen Bond ◽  
Long Range ◽  
Intermolecular Hydrogen Bond ◽  
Lone Pair ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Hydroxyl Group ◽  
Trans Orientation ◽  
Solvent Molecules ◽  
Spin Spin Coupling

The 13C nuclear magnetic resonance chemical shifts and the long-range 13C,13C spin–spin coupling constants are reported for 23 thioanisole derivatives enriched in 13C at the methyl position. For para and meta substituted thioanisole derivatives, nJ(C,C) (n being the formal number of bonds intervening between the coupled nuclei) can be related to functions of the angle by which the thiomethyl group twists out of the aromatic plane. For n = 3,4,5, the ensuing relationships yield estimates of the twofold barriers to rotation about the C(1)—S bond. The barrier is lower in ethyl phenyl sulfide than in thioanisole derivatives. Complications arise for ortho substituted thioanisole derivatives but estimates of the torsional motion about the C(1)—S bond can be obtained from the observed nJ(C,C). Among the complications is the expected fact that 3J(C,C), which is shown to be larger in the cis than the trans orientation of the intervening bonds ("anti-Karplus" behaviour), is perturbed by the substituent attached to the coupled nucleus. It is confirmed that in 2-hydroxythioanisole the thiomethyl group is oriented effectively perpendicular to the benzene plane, attributable to a stereospecific hydrogen bond between the hydroxyl group and the 3p lone-pair on the sulfur atom. In acetone-d6 solution, an equilibrium exists between this conformation and one in which an intermolecular hydrogen bond exists with solvent molecules. In the latter, the thiomethyl group prefers a coplanar orientation. In 2-aminothioanisole, the thiomethyl group twists out of the plane by about 60° so as to optimize the N—H … 3p interaction. This twist angle is changed very little in acetone-d6 solution because the second N—H bond can hydrogen bond to the solvent molecules without disrupting the intramolecular N—H … 3p interaction. It is also shown that the chemical shift of the 13C nucleus in the methyl group is a good conformational indicator in meta and para substituted thioanisoles. Therefore it can be used as such for molecules in which nJ(C,C) is difficult to find, in 1,4-dithiomethylbenzene, for example.

1h JFH coupling in 2-fluorophenol revisited: Is intramolecular hydrogen bond responsible for this long-range coupling?

2011 ◽  
Vol 49 (12) ◽  
pp. 763-767 ◽  
Author(s):  
Rodrigo A. Cormanich ◽  
Marilua A. Moreira ◽  
Matheus P. Freitas ◽  
Teodorico C. Ramalho ◽  
Cléber P. A. Anconi ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Long Range ◽  
Intramolecular Hydrogen Bond ◽  
Intramolecular Hydrogen

X-ray Evidence for the Acentric Position of the Hydrogen Atom in a Short A Type Hydrogen Bond

1971 ◽  
Vol 229 (4) ◽  
pp. 120-121 ◽  
Author(s):  
J. KROON ◽  
J. A. KANTERS ◽  
A. F. PEERDEMAN
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Atom ◽  
X Ray ◽  
Type Hydrogen Bond
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