Synthesis of chiral spiro 3-oxazolin-5-one 3-oxides (chiral nitrones) via a nitrosoketene intermediate and their asymmetric 1,3-dipolar cycloaddition reactions leading to the EPC synthesis of modified amino acids
作者:Nobuya Katagiri、Makoto Okada、Yoshihiro Morishita、Chikara Kaneko
DOI:10.1016/s0040-4020(97)00284-6
日期:1997.4
Cycloaddition of chiral cyclic ketones such as (−)-menthone, (+)-nopinone, and (+)-camphenilone to nitrosoketene generated by thermolysis of 5-hydroxyimino-2,2-dimethyl-1,3-dioxane-4,6-dione gave the corresponding chiral spiro 3-oxazolin-5-one 3-oxides (chiral cyclic nitrones). These nitrones underwent asymmetric 1,3-dipolar cycloaddition reactions with electron rich olefins to give the corresponding
通过5-羟基亚氨基-2,2-二甲基-1,3-二恶烷-4,6的热解生成的亚硝基烯酮中手性环酮(如(-)-薄荷酮,(+)-去甲酮和(+)-萘醌)的环加成反应-二酮得到相应的手性螺-3-恶唑啉-5-酮3-氧化物(手性环硝酮)。这些硝酮与富含电子的烯烃进行不对称的1,3-偶极环加成反应,得到具有高非对映选择性的相应的恶唑烷衍生物,将其转化为光学纯的氨基酸。