ACS Combinatorial Science
LETTER
Hydrazones were prepared in excellent isolated yields in only 5 min,
by reacting a wide range of phenylhydrazines with 2-, 3-, and
4-acetylpyridine. The method was successfully extended to other
carbonyl compounds. High power microwave heating allowed us to
slash the time of the reaction. At the same time, the external cooling
precluded the decomposition of both starting materials and reaction
products. Finally, the open vessel mode could lead to a rapid scale
up of the reaction to multigram level.
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lyzed Greener Synthesis of Hydrazones in Aqueous Medium Using
Microwaves. Tetrahedron Lett. 2007, 48, 5649–5652.
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(12) Lemster, T.; Pindur, U.; Lenglet, G.; Depauw, S.; Dassi, C.;
David-Cordonnier, M.-H. Photochemical Electrocyclisation of 3-Viny-
lindoles to Pyrido[2,3-a]-, Pyrido[4,3-a]-, and Thieno[2,3-a]-carbazoles:
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(13) Kappe, C. O.; Dallinger, D.; Murphree, S. S. Practical Microwave
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pp 177-178.
’ ASSOCIATED CONTENT
S
Supporting Information. Experimental procedures, charac-
b
terization data of all synthesized compounds, example of microwave
output graphics, and copies of 1H NMR spectra of compounds
20-23, 25, 26, 31-35, 37-41, and 55-59. This information is
’ AUTHOR INFORMATION
Corresponding Author
*E-mail: giuseppe.laregina@uniroma1.it. Phone: þ39 0649913404.
Fax: þ39 0649913133.
’ ACKNOWLEDGMENT
Authors wish to thank Ministero dell'Universitꢀa e della Ricerca
(PRIN 2008, Prot. n 200879X9N9), Istituto Pasteur, Fondazione
Cenci Bolognetti (Grant 2009), and FILAS (Finanziaria Laziale
di Sviluppo, Grant 2010) for financial support and Andrea Rota
(CEM srl, Italy) for skillful technical assistance.
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dx.doi.org/10.1021/co100015b |ACS Comb. Sci. 2011, 13, 2–6