N-Chlorination of secondary amides. II. Effects of substituents on rates of N-chlorination

1969 ◽  
Vol 47 (18) ◽  
pp. 3289-3297 ◽  
Author(s):  
E. W. C. W. Thomm ◽  
M. Wayman
Keyword(s):  
Hydrogen Bond ◽  
Oxygen Atom ◽  
Reaction Mechanisms ◽  
Bond Formation ◽  
Low Ph ◽  
Reverse Order ◽  
Primary Reaction ◽  
Hydrogen Bond Formation ◽  
Cl Atom ◽  
Secondary Amides

Various secondary amides have been N-chlorinated, at high and at low pH. The reactivity of the chlorinating reagents with all the amides investigated was found to have the sequence[Formula: see text]The substituent groups R1 and R2 of the amide [Formula: see text] were found to have large effects on the rate of chlorination. With the three molecular chlorinating agents, the reactivity of the amides was found to be in the order[Formula: see text]With hypochlorite ion the reverse order of reactivity was observed. These results are discussed and reaction mechanisms proposed. It is proposed that, when a hypochlorite ion is a chlorinating agent, the primary reaction is hydrogen bond formation between the amido hydrogen and the hypochlorite oxygen atom, but that the donation of electrons from the amido N to the Cl atom is the primary reaction with the molecular chlorinating agents.

Anharmonicity, solvent effects, and hydrogen bonding: NH stretching vibrations

1970 ◽  
Vol 48 (14) ◽  
pp. 2197-2203 ◽  
Author(s):  
A. Foldes ◽  
C. Sandorfy
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Solvent Effects ◽  
Bond Formation ◽  
Hydrogen Bond Formation ◽  
Stretching Vibration ◽  
Solvent Shifts ◽  
Stretching Vibrations ◽  
Secondary Amides ◽  
Influence Of Solvent

The influence of solvent effects and hydrogen bond formation on the anharmonicity of the NH stretching vibration of simple secondary amides, lactams, anilides, indole, pyrrole, and imidazole have been studied; and the frequencies of the first and second overtones, their half widths and solvent shifts measured. The validity of Buckingham's theory is established in the case of inert solvents; whereas the second order perturbation treatments are shown to be inapplicable to the case of hydrogen bonding solvents. All NH stretching modes seem to exhibit the same anharmonic behavior which is very different from that of OH vibrations.

A Low Temperature Infrared Study of Hydrogen Bonding in N-Alkylacetamides

1973 ◽  
Vol 51 (21) ◽  
pp. 3640-3646 ◽  
Author(s):  
Marie-Claude Bernard-Houplain ◽  
C. Sandorfy
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Low Temperature ◽  
Infrared Spectra ◽  
Bond Formation ◽  
Coupling Constant ◽  
Infrared Study ◽  
Hydrogen Bond Formation ◽  
Stretching Vibration ◽  
Secondary Amides

The infrared spectra of N-methylacetamide and two other secondary amides were measured in solution at temperatures ranging from 22 to −190 °C in both the fundamental and the overtone regions. At least two hydrogen bonded species are found as association increases with decreasing temperature. The effect of hydrogen bond formation on the anharmonicity of the NH stretching vibration and on the NH stretching – NH bending coupling constant is examined.

Vapochromism induced by intermolecular electron transfer coupled with hydrogen-bond formation in zinc dithiolene complex

2020 ◽  
Vol 8 (42) ◽  
pp. 14939-14947
Author(s):  
So Yokomori ◽  
Shun Dekura ◽  
Tomoko Fujino ◽  
Mitsuaki Kawamura ◽  
Taisuke Ozaki ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Electron Transfer ◽  
Bond Formation ◽  
Intermolecular Electron Transfer ◽  
Hydrogen Bond Formation ◽  
Complex Crystal

A novel vapochromic mechanism by intermolecular electron transfer coupled with hydrogen-bond formation was realized in a zinc dithiolene complex crystal.

Diverse mechanisms of carbon-hydrogen bond formation through binuclear reductive elimination reactions

1982 ◽  
Vol 104 (2) ◽  
pp. 619-621 ◽  
Author(s):  
Mario J. Nappa ◽  
Roberto Santi ◽  
Steven P. Diefenbach ◽  
Jack Halpern
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Reductive Elimination ◽  
Hydrogen Bond Formation ◽  
Elimination Reactions

Theoretical analysis of the (HNO)2, (HNO···HNS), and (HNS)2 dimers — A case of red and blue shifts of N–H stretching frequency

2010 ◽  
Vol 88 (8) ◽  
pp. 849-857 ◽  
Author(s):  
Nguyen Tien Trung ◽  
Tran Thanh Hue ◽  
Minh Tho Nguyen
Keyword(s):  
Hydrogen Bond ◽  
Quantum Chemical ◽  
Bond Formation ◽  
Blue Shift ◽  
Proton Donor ◽  
Basis Sets ◽  
Coupled Cluster ◽  
Hydrogen Bond Formation ◽  
Length Contraction ◽  
Moller Plesset

The hydrogen-bonded interactions in the simple (HNZ)2 dimers, with Z = O and S, were investigated using quantum chemical calculations with the second-order Møller–Plesset perturbation (MP2), coupled-cluster with single, double (CCSD), and triple excitations (CCSD(T)) methods in conjunction with the 6-311++G(2d,2p), aug-cc-pVDZ, and aug-cc-pVTZ basis sets. Six-membered cyclic structures were found to be stable complexes for the dimers (HNO)2, (HNS)2, and (HNO–HNS). The pair (HNS)2 has the largest complexation energy (–11 kJ/mol), and (HNO)2 the smallest one (–9 kJ/mol). A bond length contraction and a frequency blue shift of the N–H bond simultaneously occur upon hydrogen bond formation of the N–H···S type, which has rarely been observed before. The stronger the intramolecular hyperconjugation and the lower the polarization of the X–H bond involved as proton donor in the hydrogen bond, the more predominant is the formation of a blue-shifting hydrogen bond.

Internal Hydrogen Bond Formation in a syn-Hydroxyepoxide

Science ◽  
1982 ◽  
Vol 215 (4533) ◽  
pp. 695-696 ◽  
Author(s):  
J. P. GLUSKER ◽  
D. E. ZACHARIAS ◽  
D. L. WHALEN ◽  
S. FRIEDMAN ◽  
T. M. POHL
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Hydrogen Bond Formation ◽  
Internal Hydrogen ◽  
Internal Hydrogen Bond

Influence of Hydrogen Bond Formation on the Photophysics ofN-(2,6-Dimethylphenyl)-2,3-naphthalimide

2004 ◽  
Vol 108 (19) ◽  
pp. 4357-4364 ◽  
Author(s):  
Attila Demeter ◽  
László Ravasz ◽  
Tibor Bérces
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Hydrogen Bond Formation

Ruthenium-catalyzed Asymmetric Dehydrative Allylic Cyclization of Chalcogen 5-Membered Heteroaromatics

Synthesis ◽  
2021 ◽  
Author(s):  
Shinji Tanaka ◽  
Shoutaro Iwase ◽  
Sena Kanda ◽  
Marie Kato ◽  
Yutaro Kiriyama ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Bond Formation ◽  
Selection Method ◽  
Allylic Alcohol ◽  
Hydrogen Bond Formation ◽  
Pyridine Carboxylic Acid ◽  
Bicyclic Compounds ◽  
Allyl Complex ◽  
Pyridine Carboxylic ◽  
High Yields

The asymmetric dehydrative intramolecular allylation reactions of furan and thiophene were performed using a cationic cyclopentadienyl-ruthenium (CpRu) complex of a chiral pyridine carboxylic acid, namely Cl-Naph-PyCOOH. Both furan and thiophene tethered with an allylic alcohol gave the corresponding bicyclic compounds in high yields and enantioselectivities using 0.1–5 mol% of catalyst. The reaction was found to proceed via a similar enantioface selection method mechanism to that previously reported by our group, which involved halogen and hydrogen bond formation, in addition to the generation of an intermediate σ-allyl complex.

Sign in / Sign up

Export Citation Format

Share Document