Microwave irradiation in solvent-free conditions:: an eco-friendly methodology to prepare indazoles, pyrazolopyridines and bipyrazoles by cycloaddition reactions

被引:74
作者
Díaz-Ortiz, A
de la Hoz, A
Langa, F
机构
[1] Univ Castilla La Mancha, Fac Quim, E-13071 Ciudad Real, Spain
[2] Univ Castilla La Mancha, Fac Ciencias Medioambiente, Toledo 45001, Spain
关键词
D O I
10.1039/b003752o
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
A study on the behaviour of vinylpyrazoles, pyrazolyl imines and pyrazolyl hydrazones as dienes or dipoles is reported. Cycloaddition of the aforementioned compounds with electron-poor reagents under microwave irradiation in solvent-free conditions permits the preparation of indazoles, pyrazolopyridines and bipyrazoles in moderate to good yields. This represents an eco-friendly, green approach to these valuable pyrazole derivatives that avoids the harsh or highly contaminant conditions involving classical heating and offers a reduction or even elimination of solvent use and recovery, simplification of the work up procedures, facility of scale up and savings in energy consumption, in addition with higher yields.
引用
收藏
页码:165 / 172
页数:8
相关论文
共 72 条
  • [1] Electron transfer from tetrathiafulvalenes to photoexcited C-70 studied by observing transient absorption in the near-IR region
    Alam, MM
    Watanabe, A
    Ito, O
    [J]. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 1997, 70 (08) : 1833 - 1838
  • [2] Efficient photoinduced electron transfer between C-60 and tetrathiafulvalenes studied by nanosecond laser photolysis
    Alam, MM
    Watanabe, A
    Ito, O
    [J]. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY, 1997, 104 (1-3) : 59 - 64
  • [3] Alkylation and arylation of pyrazoles under solvent-free conditions:: Conventional heating versus microwave irradiation
    Almena, I
    Díez-Barra, E
    de la Hoz, A
    Ruiz, J
    Sánchez-Migallón, A
    Elguero, J
    [J]. JOURNAL OF HETEROCYCLIC CHEMISTRY, 1998, 35 (06) : 1263 - 1268
  • [4] Efficient tautomerization hydrazone-azomethine imine under microwave irradiation.: Synthesis of [4,3′] and [5,3′]bipyrazoles
    Arrieta, A
    Carrillo, JR
    Cossío, FP
    Díaz-Ortiz, A
    Gómez-Escalonilla, MJ
    de la Hoz, A
    Langa, F
    Moreno, A
    [J]. TETRAHEDRON, 1998, 54 (43) : 13167 - 13180
  • [5] Hetero-Diels-Alder reactions of homochiral 1,2-diaza-1,3-butadienes with diethyl azodicarboxylate under microwave irradiation.: Theoretical rationale of the stereochemical outcome
    Avalos, M
    Babiano, R
    Cintas, P
    Clemente, FR
    Jiménez, JL
    Palacios, JC
    Sánchez, JB
    [J]. JOURNAL OF ORGANIC CHEMISTRY, 1999, 64 (17) : 6297 - 6305
  • [6] BISTOCCHI GA, 1981, FARMACO-ED SCI, V36, P315
  • [7] Microwave-assisted aqueous Suzuki cross-coupling reactions
    Blettner, CG
    König, WA
    Stenzel, W
    Schotten, T
    [J]. JOURNAL OF ORGANIC CHEMISTRY, 1999, 64 (11) : 3885 - 3890
  • [8] BRAM G, 1991, CHEM IND-LONDON, P396
  • [9] Rapid microwave-induced palladium-catalyzed asymmetric allylic alkylation
    Bremberg, U
    Larhed, M
    Moberg, C
    Hallberg, A
    [J]. JOURNAL OF ORGANIC CHEMISTRY, 1999, 64 (04) : 1082 - 1083
  • [10] BRUNO O, 1993, FARMACO, V48, P949