期刊论文详细信息
Journal of the Brazilian Chemical Society
Pyrazole synthesis under microwave irradiation and solvent-free conditions
Prola, Liziê D. T.1  Zanatta, Nilo1  Buriol, Lilian1  Bonacorso, Helio G.1  Martins, Marcos A. P.1  Moreira, Dayse N.1  Marzari, Mara R. B.1  Frizzo, Clarissa P.1  Universidade Federal de Santa Maria, Santa Maria, Brazil1 
关键词: microwave irradiation;    solvent-free;    pyrazoles;    cyclocondensation reactions;   
DOI  :  10.1590/S0103-50532010000600012
学科分类:化学(综合)
来源: SciELO
PDF
【 摘 要 】

This paper presents a study of solvent-free reaction conditions using microwave irradiation (MW) to obtain 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles by the cyclocondensation reaction of 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones [CF3C(O)CH=C(R1)OR, where R/R1 = Et/H, Me/Me and Me/Ph] with hydrazines [NH2NH-R2, where R2 = CO2Me, Ph, CH2CH2OH]. Some reactions were performed under the same reaction conditions using methanol as solvent. The results obtained using MW equipment for synthesis under solvent-free conditions were also compared with those described in literature for conventional thermal heating and heating with a domestic MW oven. In general, the products furnished by reaction in MW equipment for synthesis presented better yields and shorter reaction times. In addition, it was demonstrated that the reaction temperature altered the formation of products for each hydrazine showing that MW equipment for synthesis is efficient for reacting hydrazines and 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones to procedure the products 4,5-dihydro-1H-pyrazoles and dehydrated pyrazoles.

【 授权许可】

Unknown   

【 预 览 】
附件列表
Files Size Format View
RO201912050581028ZK.pdf 4375KB PDF download
  文献评价指标  
  下载次数:3次 浏览次数:4次