Cyclocondensation between fatty acid hydrazides and 1,1,1-trifluoro-4-alkoxy-3-alken-2-ones: Introducing a trifluoromethylated head onto fatty acid moieties
作者:Wystan K. O. Teixeira、Helena A. Gonçalves、Débora L. de Mello、Sidnei Moura、Darlene C. Flores、Alex F. C. Flores
DOI:10.1080/00397911.2017.1364769
日期:2017.11.17
ABSTRACT This paper reports the regioselective synthesis of new trifluoromethylated lipid derivatives, namely, 1-(5-hydroxy-5-trifluoromethyl-3-alkyl-4,5-dihydro-1H-pyrazol-1-yl)alkan-1-ones, through cyclocondensation reactions between a series of fatty hydrazides (palmitoyl, stearoyl, and oleoyl hydrazides) obtained from fatty acids from renewable resources (1,1,1-trifluoro-4-alkoxy-3-alken-2-ones
摘要 本文报道了新型三氟甲基化脂质衍生物的区域选择性合成,即 1-(5-羟基-5-三氟甲基-3-烷基-4,5-二氢-1H-吡唑-1-基)烷-1-酮,通过从可再生资源(1,1,1-trifluoro-4-alkoxy-3-alken-2-ones [F3CC(O) CH˭C(R1)OR,其中R1 = H和R˭Et;R1 = –(CH2)6CH3、–(CH2)6CH3、–(CH2)8CH3、–(CH2)9CH3、–(CH2)10CH3、– (CH2)12CH3、–(CH2)2Ph] 和 R˭Me)。实验观察表明,5-羟基-5-三氟甲基-4,5-二氢-1H-吡唑(5-7)的亲脂特性阻止了酸催化脱水至1H-吡唑环的芳构化,尽管在一些环缩合反应中获得了一定比例的芳族衍生物 1-(5-三氟甲基-3-烷基-1H-吡唑-1-基)链烷-1-酮。使用多核 (1H、13C、19F) NMR 光谱对所有产品进行表征。图形概要