Hindered Internal Rotation About Aryl C—N Bonds in Aryl Substituted Heterocyclic Compounds: 3-Aryl-2-benzyl-4(3H)-quinazolinones

1975 ◽  
Vol 53 (22) ◽  
pp. 3431-3434 ◽  
Author(s):  
Lawrence D. Colebrook ◽  
H. Gwynne Giles
Keyword(s):  
Free Energy ◽  
Magnetic Resonance ◽  
Internal Rotation ◽  
Heterocyclic Compounds ◽  
Proton Magnetic Resonance ◽  
Energy Barriers ◽  
Magnetic Resonance Spectra

The proton magnetic resonance spectra of a number of 3-aryl substituted 2-benzyl-4(3H) quinazolinones indicate that internal rotation about the aryl C—N bond is highly hindered. Substantial free energy barriers (18.9–19.8 kcal/mol) have been measured even when the aryl groups lack bulky ortho substituents.

The reaction of 1-Fluoro-2,4-dinitrobenzene with some NH-Heterocyclic compounds

1966 ◽  
Vol 19 (10) ◽  
pp. 1935 ◽  
Author(s):  
JFK Wilshire
Keyword(s):  
Charge Transfer ◽  
Magnetic Resonance ◽  
Heterocyclic Compounds ◽  
Proton Magnetic Resonance ◽  
Charge Transfer Complexes ◽  
Heteroaromatic Compounds ◽  
Magnetic Resonance Spectra

I-Fluoro-2,4-dinitrobenzene reacts with a wide variety of NH- heteroaromatic compounds to give N-2,4-dinitrophenyl derivatives. The proton magnetic resonance spectra of these derivatives are discussed. With some indoles (and pyrene), 1-fluoro-2,4-dinitrobenzene forms stable charge-transfer complexes.

The preparation of 2-Fluoro-5-nitrobenzonitrile and the proton magnetic resonance spectra of some compounds containing the N-(2-Cyano-4-nitrophenyl) group

1967 ◽  
Vol 20 (8) ◽  
pp. 1663 ◽  
Author(s):  
JFK Wilshire
Keyword(s):  
Amino Acids ◽  
Magnetic Resonance ◽  
Nitro Group ◽  
Proton Magnetic Resonance ◽  
Cyano Group ◽  
Aromatic Nucleus ◽  
Heteroaromatic Compounds ◽  
Magnetic Resonance Spectra

2-Fluoro-5-nitrobenzonitrile, an analogue of 1-fluoro-2,4- dinitrobenzene, in which the 2-nitro group has been replaced by a cyano group, has been prepared and made to react with several amines, amino acids, and NH-heteroaromatic compounds. The proton magnetic resonance spectra of some of the resultant N-(2-cyano-4-nitrophenyl) derivatives were compared with the spectra of the corresponding N-(2,4- dinitrophenyl) derivatives and furnish further evidence that the ortho nitro group of the latter derivatives is rotated out of the plane of the aromatic nucleus.

Investigation and Identification of the Bromination Products of Dimethoxyamphetamines

1976 ◽  
Vol 59 (5) ◽  
pp. 1162-1169
Author(s):  
Keith Bailey ◽  
Denise R Gagné ◽  
Richard K Pike
Keyword(s):  
Magnetic Resonance ◽  
Qualitative Analysis ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Infrared Spectra ◽  
Proton Magnetic Resonance ◽  
Positive Identification ◽  
Aromatic Bromination ◽  
Layer Chromatography ◽  
Magnetic Resonance Spectra

Abstract The qualitative analysis of the aromatic bromination products of the 6 isomeric dimethoxyamphetamines and their hydrochloride or hydrobromide salts is described. Their ultraviolet, mass, and proton magnetic resonance spectra are not sufficiently different for distinction but infrared spectra allow a positive identification to be made and reference spectra are provided for the bromination products of 2,4-, 2,5-, 2,6-, 4,5-, and 3,5-dimethoxyamphetamines. The application of gas-liquid and thin layer chromatography for the analysis of these products is discussed. The bromination of 2,3-dimethoxyamphetamine consistently gave mixtures which could not be separated satisfactorily; spectra are included for completeness of the comparison of products.

Sign in / Sign up

Export Citation Format

Share Document