New type of cyclization of .alpha.,.beta.,.chi.,.psi.-unsaturated dioic acid esters through tandem conjugate additions by using lithium N-benzyl-N-(trimethylsilyl)amide as a nitrogen nucleophile
New type of cyclization of .alpha.,.beta.,.chi.,.psi.-unsaturated dioic acid esters through tandem conjugate additions by using lithium N-benzyl-N-(trimethylsilyl)amide as a nitrogen nucleophile
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使用 N-苄基-N-(三甲基甲硅烷基)酰胺锂作为氮亲核试剂通过串联共轭加成实现 α,β,chi.,psi.-不饱和二酸酯的新型环化
DOI：
10.1021/jo00037a034
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发表时间：
1992
影响因子：
3.6
通讯作者：
Yoshinori Yamamoto
中科院分区：
文献类型：
--
作者：
T. Uyehara;N. Shida;Yoshinori Yamamoto
(2E，6E)-2，6-八二烯二酸二甲酯与N-苄基-N-(三甲基硅基)胺锂反应，通过串联共轭加成得到5-外三环产物甲基3-(N-benzylamino)-2-(methoxycarbonyl)cyclopentane-1-acetates，。相关的6-外三角环化反应立体选择性地进行，得到乙基c-3-(N-benzylamino)-t-2-(ethoxycarbonyl)cyclohexane-1-acetate.。与5-和6-外触发环化反应相比，未发生7-外触发环化反应
Treatment of dimethyl (2E,6E)-2,6-octadienedioate with lithium N-benzyl-N-(trimethylsilyl)amide (LSA) gave 5-exo-trig ring products, methyl 3-(N-benzylamino)-2-(methoxycarbonyl)cyclopentane-1-acetates, through tandem conjugate additions. The related 6-exo-trig cyclization proceeded stereoselectively to give ethyl c-3-(N-benzylamino)-t-2-(ethoxycarbonyl)cyclohexane-1-acetate. In contrast with the 5- and 6-exo-trig cyclization, no 7-exo-trig cyclization occured