作者:Dieter Enders、Ilka Meyer、Jan Runsink、Gerhard Raabe
DOI:10.1016/s0040-4020(98)00638-3
日期:1998.9
5S)-2,2-dimethyl-4-phenyl-1,3-dioxan-5-ylamine (1), were heated with a variety of aromatic aldehydes in chlorobenzene under reflux. The in situ generated 1,3-dipols were trapped with fumaric acid ester, fumaric acid nitrile or N-phenylmaleimide, respectively, that were present in excess in the reaction mixture. The cycloadducts 4a-e, 5a-f were formed in 78–91% and 67–100% yield as mixture of exolendo-isomers
将基于(4 S,5 S)-2,2-二甲基-4-苯基-1,3-二恶烷-5-基胺(1)的仲胺2a-c与各种芳香醛在氯苯中于回流。该原位生成的1,3- dipols被困用富马酸酯,富马酸腈或Ñ苯基马来分别,即存在于过量于反应混合物中。环加成化合物4a-e,5a-f以exolendo-异构体的混合物形式形成,产率为78-91%和67-100%(endo:exo = 30-65:70-35)。这些异构体形成非对映异构纯的化合物(日≥96%)。