Studies on the Nuclear Magnetic Resonance Spectra of (E)-1-Aryl-3-(2- and 3-thienyl)-2-propenones and Unique Observation of<sup>4</sup>J and<sup>5</sup>J Coupling in Their<sup>1</sup>H-<sup>1</sup>H COSY
作者:In-Sook HanLee、Hyun-Ju Jeon、Chang-Kiu Lee
DOI:10.5012/bkcs.2011.32.2.687
日期:2011.2.20
$^1H$ and $^13}C$ NMR spectra of series of (E)-1-aryl-(2- and 3-thienyl)-2-propenones, that are aldol condensation products between 2- and 3-thiophenecarbaldehydes and m- and p-substituted acetophenones, were examined to make complete assignments of the chemical shifts. Long range couplings, $^4J$ and $^5J$, are observed in the $^1H-^1H$ COSY of both 2- and 3-thienyl compounds, which makes the elucidation of the conformation in solution possible. In contrast, the 2-furyl analogue shows the long range coupling phenomena, but the 3-furyl and phenyl analogues do not show similar phenomena.
Substituent Chemical Shifts of (E)-1-Aryl-3-thienylpropen-1-ones
作者:In-Sook HanLee、Hyun-Ju Jeon、Ji-Sook Yu、Chang-Kiu Lee
DOI:10.5012/bkcs.2010.31.6.1689
日期:2010.6.20
Substituentchemicalshifts were examined for the 2- and 3-thiophene derivatives of chalcone and compared to the thiophene series of derivatives with the phenyl series. The chemicalshift values for the α-carbons of the enones showed and inverse correlation with the Hammett σ values, but the correlation coefficients were moderate (r = 0.836 - 0.878). On the other hand, the β-carbons showed a normal
Evaluation of Silica-H2SO4 as an Efficient Heterogeneous Catalyst for the Synthesis of Chalcones
作者:Aeysha Sultan、Abdul Raza、Muhammad Abbas、Khalid Khan、Muhammad Tahir、Nazamid Saari
DOI:10.3390/molecules180810081
日期:——
We report an efficient silica-H2SO4 mediated synthesis of a variety of chalcones that afforded the targeted compounds in very good yield compared to base catalyzed solvent free conditions as well as acid or base catalyzed refluxing conditions.
Studies of NMR Chemical Shifts of Chalcone Derivatives of Five‐membered Monoheterocycles and Determination of Aromaticity Indices
作者:Eun Jeong Jeong、In‐Sook Han Lee
DOI:10.1002/bkcs.11749
日期:2019.7
(E)‐1‐heteroaryl‐3‐arylpropen‐1‐ones. The 13C chemicalshift values (δC) of the chalcone derivatives were determined in order to find if they correlated with the Hammett σ values. A good correlation, especially for the β‐C for both series, was found for the 13C chemicalshift values (δC) of the chalcone derivatives with the Hammett σ values. The chemicalshift values of the β‐C of the heterocyclic compounds