Dynamic 1
H NMR study around the carbon-carbon single bond and partial carbon-carbon double bond in the two particular phosphorus ylides and in an enaminoester

The stereochemical course of the photoaddition of nitrosamines to a carbon–carbon double bond was shown to follow a free radical mechanism initiated by aminium radicals. The photoaddition to cyclohexene was highly stereoselective in which the addendum approached in anti-diaxial mode. Similar photoadditions to cis- and trans-2-butenes were less stereoselective, giving mixtures of the erythro- and threo-adducts, owing to the rotation of the carbon-carbon single bond in the intermediate stage.

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Stereochemistry of some substituted 2-furyl- and 2-thienyl ethylene derivatives. 1H NMR study

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19823412 ◽

1982 ◽

Vol 47 (12) ◽

pp. 3412-3417 ◽

Cited By ~ 8

Author(s):

Miloslava Dandárová ◽

Jaroslav Kováč ◽

Daniel Végh ◽

Vladimír Žvak

Keyword(s):

Double Bond ◽

Nmr Spectroscopy ◽

1H Nmr ◽

Side Chain ◽

H Nmr ◽

Nmr Study ◽

Thiophene Derivatives

Stereochemistry of (E)- and (Z)-1-(5-nitro-2-furyl)-2-Y-ethylenes and 1-(5-nitro-2-thienyl)-2-Y-ethylenes (where Y = CH3O, 4-CH3C6H4O, N3 and Br) and of E and Z isomers of methyl 2-methyl-3-(2-furyl)propenoate and methyl 2-methyl-3-(2-thienyl)propenoate was studied by 1H NMR spectroscopy. With 1-(5-nitro-2-furyl)-2-Y-ethylenes, it was found that the preferred conformation of the furyl substituent relative to the side chain double bond is s-trans in the E isomers and s-cis in the Z isomers. The s-cis conformation is prevailing in both isomers of methyl 2-methyl-3-(2-furyl)propenoate. The E and Z isomers of all studied thiophene derivatives exist in the s-trans conformation.

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Dynamic NMR study of rotation around carbon-carbon double bond in esters of ?-nitro-?-arylaminoacrylic acids

Bulletin of the Academy of Sciences of the USSR Division of Chemical Science ◽

10.1007/bf00924584 ◽

1977 ◽

Vol 26 (12) ◽

pp. 2610-2612

Author(s):

V. I. Bakhmutov ◽

V. A. Burmistrov ◽

K. K. Babievskii ◽

V. M. Belikov ◽

�. I. Fedin

Keyword(s):

Double Bond ◽

Dynamic Nmr ◽

Carbon Double Bond ◽

Nmr Study

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Synthesis and Dynamic NMR Study of Fluorinated Dialkyl 2-[(tert-butylimino)-methylene]-3-[(2-alkoxy-2-oxoacetyl)-2-fluoroanilino]-succinates

Journal of Chemical Research ◽

10.3184/030823405774663372 ◽

2005 ◽

Vol 2005 (8) ◽

pp. 537-539 ◽

Cited By ~ 3

Author(s):

Issa Yavari ◽

Farough Nasiri ◽

Hoorieh Djahaniani ◽

Hamid R. Bijanzadeh

Keyword(s):

Free Energy ◽

Nmr Spectra ◽

Dynamic Nmr ◽

Single Bond ◽

Aryl Group ◽

Restricted Rotation ◽

H Nmr ◽

Dialkyl Acetylenedicarboxylates ◽

Free Energy Of Activation ◽

Nmr Study

The 1:1 adduct produced in the reaction between tert-butyl isocyanide and dialkyl acetylenedicarboxylates was trapped by alkyl 2-fluoro-anilino-2-oxo-acetates or ethyl 2-oxo-2-(trifluoromethylanilino)-acetate to produce functionalised ketenimines in good yields. Dynamic NMR effects were observed in the 1H NMR spectra of these compounds as a result of restricted rotation around the single bond linking the aryl group to the ketenimine system. The free energy of activation (ΔG≠) for this process is 64.9–66.5 kJ mol−1.

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