Unexpected diastereotopic behaviour in the ¹H NMR spectrum of 1,4-dihydropyridine derivatives triggered by chiral and prochiral centres

DaSilva, Jacqueline Argüello; Barría, Claudio Saitz; Jullian, Carolina; Navarrete, Patricio Andrés González; Vergara, Luis Núñez; Squella, J.A.

doi:10.1590/s0103-50532005000100018

Cited by 13 publications

(1 citation statement)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is not an unexpected finding because it has been determined that the degree of anisochrony is not always a function of the distance from the chiral center. 21,22 Additional steric interaction between this substituent and the phenyl ring at C-4 would explain the multiplicity of the signal (AB system) corresponding to these protons. In this case, the spin system cannot be resolved even by using homonuclear decoupling.…”

Section: Resultsmentioning

confidence: 99%

¹H and ¹³C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

Salfrán

Suárez

Molero

et al. 2006

Magnetic Reson in Chemistry

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 99%

¹H and ¹³C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

Salfrán

Suárez

Molero

et al. 2006

Magnetic Reson in Chemistry

View full text Add to dashboard Cite

show abstract

Chemical modification and structural rearrangements of polyketone‐based polymer membrane

Ataollahi

Girardi

Cappelletto

et al. 2017

J of Applied Polymer Sci

View full text Add to dashboard Cite

Alternating polyketones constitute a very interesting class of polymers, which can be modified for the preparation of functional polymers. The chemical modification of polyketone using 1,2-diaminopropane was used to prepare a conductive membrane. This paper is focused on the synthesis and structural rearrangements of polyamine for preparing anion-exchange membranes by the solvent casting technique. According to the Paal-Knorr mechanism, 1,4-dicarbonyl of polyketone reacts with 1,2-diaminopropane to form a pyrrole ring along the polyketone backbone. In addition, the so-modified polyamines can undergo structural rearrangements to form N-substituted pyrrole crosslinked with dihydropyridine units. The conversion degree and the N content are quite low. The pathway reactions have been proposed on the basis of 1H-NMR, ultraviolet–visible, and Fourier transform infrared results. Scanning electron microscopy,differential scanning calorimetry, and X-ray diffraction techniques were used to study the morphological, thermal, and structural characteristics of the modified polyketone, as well as the correspondoing membrane. The experimental results indicated that the membrane is a potential candidate for energy conversion technolog

show abstract

Sustainable Synthesis, NMR and Computational Study of Isobutylmesitylphosphine

2021

View full text Add to dashboard Cite

The alkyl‐aryl‐substituted secondary phosphines i‐Bu(Mes)PH and Cy(Mes)PH are obtained from the reaction of the electrochemically generated organonickel sigma‐complex [NiBr(Mes)(bpy)] (Mes=2,4,6‐trimethylphenyl; bpy=2,2′‐bipyridine) with primary phosphines i‐BuPH2 and CyPH2, respectively. Detailed multinuclear NMR spectroscopy and quantum‐chemical calculations were used to assign the diastereotopic protons of i‐Bu(Mes)PH.

show abstract

Unexpected diastereotopic behaviour in the ¹H NMR spectrum of 1,4-dihydropyridine derivatives triggered by chiral and prochiral centres

Cited by 13 publications

References 11 publications

¹H and ¹³C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

¹H and ¹³C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

Chemical modification and structural rearrangements of polyketone‐based polymer membrane

Sustainable Synthesis, NMR and Computational Study of Isobutylmesitylphosphine

Contact Info

Product

Resources

About

Unexpected diastereotopic behaviour in the ¹H NMR spectrum of 1,4-dihydropyridine derivatives triggered by chiral and prochiral centres

Cited by 13 publications

References 11 publications

1H and 13C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

1H and 13C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

Chemical modification and structural rearrangements of polyketone‐based polymer membrane

Sustainable Synthesis, NMR and Computational Study of Isobutylmesitylphosphine

Contact Info

Product

Resources

About

¹H and ¹³C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives

¹H and ¹³C spectral assignment of 4‐aryl‐1,4,5,6,7,8‐hexahydro‐2,7,7,5‐oxo‐quinolines 3‐substituted derivatives