| Title |
Ring-closing metathesis as a key step to construct 2,6-dihydropyrano[2,3-c]pyrazole ring system / |
| Authors |
Bieliauskas, Aurimas ; Krikštolaitytė, Sonata ; Holzer, Wolfgang ; Šačkus, Algirdas |
| DOI |
10.24820/ark.5550190.p010.407 |
| Full Text |
|
| Is Part of |
Arkivoc.. Gainesville, FL : ARKAT USA. 2018, vol. 2018, iss. 5, p. 296-307.. ISSN 1551-7004. eISSN 1551-7012 |
| Keywords [eng] |
1-phenylpyrazol-3-ol ; wittig olefination ; ring-closing metathesis ; 2,6-dihydropyrano[2,3-c]pyrazole |
| Abstract [eng] |
A simple and efficient synthetic route to the 2,6-dihydropyrano[2,3-c]pyrazole ring system was developed by employing ring-closing metathesis (RCM) as a key step. The required diene substrate for the RCM reaction was prepared by a three-step procedure starting form 1-phenyl-1H-pyrazol-3-ol. Treatment of the obtained 4-ethenyl-1-phenyl-3-[(prop-2-en-1-yl)oxy]-1H-pyrazole with Grubbs‘ first-generation catalyst afforded the target 2-phenyl-2,6-dihydropyrano[2,3-c]pyrazole. 2-(4-Fluorophenyl)- and 2-(4-bromophenyl)-2,6-dihydropyrano[2,3-c]pyrazole were synthesized by an analogous way. The structures of the obtained heterocyclic products were unequivocally confirmed by detailed 1H, 13C, 15N and 19F NMR spectroscopic experiments and HRMS measurements. The optical properties of 2-phenyl-2,6-dihydropyrano[2,3-c]pyrazole were studied by UV–Vis and fluorescence spectroscopy. |
| Published |
Gainesville, FL : ARKAT USA |
| Type |
Journal article |
| Language |
English |
| Publication date |
2018 |
| CC license |
|
