An isomerization—1,3-dipolar cycloaddition tandem reaction towards the synthesis of 3-aryl-4-methyl-5-O-substituted isoxazolines from O-allyl compounds
作者:Stanisław Krompiec、Piotr Bujak、Joanna Malarz、Michał Krompiec、Łukasz Skórka、Tadeusz Pluta、Witold Danikiewicz、Magdalena Kania、Joachim Kusz
DOI:10.1016/j.tet.2012.05.027
日期:2012.7
3-dipolar cycloaddition (1,3-DC) to nitrile oxides is presented. The influence of the heteroatom in Ph-X-CHCHCH3 (X=O, S, or Se) on the regio- and stereoselectivity of ArCNO 1,3-cycloaddition to these dipolarophiles is analyzed as well. The dipolarophiles were obtained via [RuClH(CO)(PPh3)3]–, [RuH2(CO)(PPh3)]– or base (KOH/18-crown-6)-catalyzed double bond migration in corresponding allyl ethers, O-allyl
通过将O-烯丙基系统串联催化异构化为O-(1-丙烯基)系统的1,3-偶极环加成反应合成3-芳基-4-甲基-5 - O-取代的异恶唑啉的新策略(1,3 -DC)表示腈氧化物。还分析了Ph-X-CH CHCH 3中的杂原子(X = O,S或Se)对ArCNO 1,3-环加成到这些双亲性化合物上的区域和立体选择性的影响。通过[RuClH(CO)(PPh 3)3 ]-,[RuH 2(CO)(PPh 3)]-或碱(KOH / 18-crown-6)催化的双键迁移在相应的烯丙基醚中获得了双极性亲和剂。,O-烯丙基缩醛,Ph S–和Ph Se –allyl系统。腈氧化物与O-(1-丙烯基)系统的环加成反应具有完全的区域选择性,而ArCNO与Ph S –(1-丙烯基)和Ph Se –(1-丙烯基)系统的反应均形成了可能的区域异构体。已经确定,在大多数ROCH CHCH 3的双极性亲虫中,1,3-DC是一致的,而对于某些RXCH