Efficient synthesis of 1,3,5-trisubstituted (pyrrol-2-yl)acetic acid esters via dual nucleophilic reactions of sulfonamides or carbamate with 4-trimethyl-siloxy-(5E)-hexen-2-ynoates: Lewis acid catalyzed SN1 and intramolecular Michael addition.
Efficient synthesis of 1,3,5-trisubstituted (pyrrol-2-yl)acetic acid esters via dual nucleophilic reactions of sulfonamides or carbamate with 4-trimethyl-siloxy-(5E)-hexen-2-ynoates: Lewis acid catalyzed SN1 and intramolecular Michael addition.
复制标题
DOI：
10.1021/ol0616485
复制
发表时间：
2006-07
期刊：
影响因子：
5.2
通讯作者：
T. Ishikawa*;T. Aikawa;S. Watanabe;S. Saito*
中科院分区：
文献类型：
--
作者：
T. Ishikawa*;T. Aikawa;S. Watanabe;S. Saito*
[反应：氨基甲酸酯或磺酰胺已被证明区域选择性地攻击由TMSOTf作用于4-（三甲基硅氧基）己-5-烯-2-炔酸酯而产生的2-丙炔基-烯丙基杂合阳离子，得到共轭的6-氨基己-4-烯-2-炔酸酯，其中发生分子内氨基-迈克尔反应，产生吡咯骨架。特别地，磺酰胺在一锅中得到1-磺酰基吡咯。
[reaction: see text] Carbamates or sulfonamides have proven to regioselectively attack 2-propynyl-allyl hybrid cations, generated by the action of TMSOTf on 4-(trimethylsioxy)hex-5-en-2-ynoates, to afford conjugated 6-aminohex-4-en-2-ynoates in which an intramolecular amino-Michael reaction took place, leading to pyrrole frameworks. In particular, the sulfonamides gave 1-sulfonylpyrroles in one pot.