Abstract
A number of vicinal amino- and (N-acetylamino)-alkylpyrazoles have been synthesized by cross-coupling reactions of iodopyrazoles with alk-1-ynes using a combination of Pd(PPh3)2Cl2 and CuI as catalyst in Et3N or with copper acetylides. The latter Stephens - Castro reaction of copper acetylides with these amino- and (N-acetylamino)-iodopyrazoles was established as a common method for the preparation of (N-acetylamino)alkynylpyrazoles. The Pd/Cu-catalyzed cross-coupling of iodopyrazoles (Sonogashira reaction) with alk-1-ynes bearing electron-releasing substituents was unsuitable for the synthesis of alkynylpyrazoles: 3- and 5-iodopyrazoles were unreactive but, in the case of 4-iodo derivatives, reductive deiodination, accompanied by homocoupling of the alk-1-yne component, was the only reaction.
| Original language | English |
|---|---|
| Pages (from-to) | 3713-3720 |
| Number of pages | 8 |
| Journal | Journal of the Chemical Society - Perkin Transactions 1 |
| Issue number | 24 |
| DOIs | |
| Publication status | Published - 21 Dec 1999 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Chemistry(all)
Cite this
Peculiarities of copper(I)- and palladium-catalyzed cross-coupling of terminal alkynes with vicinal amino- and (N-acetylamino)-iodopyrazoles. Synthesis of alkynylaminopyrazoles. / Tretyakov, Eugene V.; Knight, David W.; Vasilevsky, Sergei F.
In: Journal of the Chemical Society - Perkin Transactions 1, No. 24, 21.12.1999, p. 3713-3720.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Peculiarities of copper(I)- and palladium-catalyzed cross-coupling of terminal alkynes with vicinal amino- and (N-acetylamino)-iodopyrazoles. Synthesis of alkynylaminopyrazoles
AU - Tretyakov, Eugene V.
AU - Knight, David W.
AU - Vasilevsky, Sergei F.
PY - 1999/12/21
Y1 - 1999/12/21
N2 - A number of vicinal amino- and (N-acetylamino)-alkylpyrazoles have been synthesized by cross-coupling reactions of iodopyrazoles with alk-1-ynes using a combination of Pd(PPh3)2Cl2 and CuI as catalyst in Et3N or with copper acetylides. The latter Stephens - Castro reaction of copper acetylides with these amino- and (N-acetylamino)-iodopyrazoles was established as a common method for the preparation of (N-acetylamino)alkynylpyrazoles. The Pd/Cu-catalyzed cross-coupling of iodopyrazoles (Sonogashira reaction) with alk-1-ynes bearing electron-releasing substituents was unsuitable for the synthesis of alkynylpyrazoles: 3- and 5-iodopyrazoles were unreactive but, in the case of 4-iodo derivatives, reductive deiodination, accompanied by homocoupling of the alk-1-yne component, was the only reaction.
AB - A number of vicinal amino- and (N-acetylamino)-alkylpyrazoles have been synthesized by cross-coupling reactions of iodopyrazoles with alk-1-ynes using a combination of Pd(PPh3)2Cl2 and CuI as catalyst in Et3N or with copper acetylides. The latter Stephens - Castro reaction of copper acetylides with these amino- and (N-acetylamino)-iodopyrazoles was established as a common method for the preparation of (N-acetylamino)alkynylpyrazoles. The Pd/Cu-catalyzed cross-coupling of iodopyrazoles (Sonogashira reaction) with alk-1-ynes bearing electron-releasing substituents was unsuitable for the synthesis of alkynylpyrazoles: 3- and 5-iodopyrazoles were unreactive but, in the case of 4-iodo derivatives, reductive deiodination, accompanied by homocoupling of the alk-1-yne component, was the only reaction.
UR - http://www.scopus.com/inward/record.url?scp=0000470208&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0000470208&partnerID=8YFLogxK
U2 - 10.1039/a903754c
DO - 10.1039/a903754c
M3 - Article
SP - 3713
EP - 3720
JO - Journal of the Chemical Society, Perkin Transactions 1
JF - Journal of the Chemical Society, Perkin Transactions 1
SN - 0300-922X
IS - 24
ER -