| Publication Type |
Journal Article |
| Title |
Gold-Catalyzed Functionalization of Semicarbazides with Terminal Alkynes to Achieve Substituted Semicarbazones |
| Authors |
Dmitry P. Zimin V Dar in Anastasiya A. Eliseeva Alexander S. Novikov Valentin A. Rassadin V. Yu. Kukushkin |
| Groups |
CCC |
| Journal |
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY |
| Year |
2019 |
| Month |
September |
| Volume |
2019 |
| Number |
35 |
| Pages |
6094-6100 |
| Abstract |
Gold-catalyzed functionalization of semicarbazides (ArNHCONHNH2) with various terminal alkynes (RC)-C-2 equivalent to CH (R-2 = Alk or Ar) in the presence of Ph3PAuNTf2 (3 mol-\%) grants a range of substituted semicarbazones (16 examples; 64-93 \%). This novel metal-catalyzed coupling proceeds under mild conditions (PhCl, 60 degrees C) and demonstrates a high functional group tolerance; the reaction is sensitive to the electronic effects of the substituents in terminal alkynes. Inspection of XRD solid-state structures of three obtained semicarbazones proved their dimerization via weak to moderate strength hydrogen bonding. The structures of the semicarbazones in solutions were studied by concentration dependent H-1 NMR and 2D NMR and these experiments proved the presence of H-bonds between two molecules. The nature and energy of H-bonding (3.8-5.1 kcal/mol), degree of electron density delocalization, and rotational barriers via various bonds in the equilibrium model structures were studied by DFT calculations at the M06-2X/6-311++G** level of theory. |
| DOI |
http://dx.doi.org/10.1002/ejoc.201901108 |
| ISBN |
|
| Publisher |
|
| Book Title |
|
| ISSN |
1434-193X |
| EISSN |
1099-0690 |
| Conference Name |
|
| Bibtex ID |
ISI:000482019000001 |
| Observations |
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