Studies on Intramolecular Diels−Alder Reactions of Furo[3,4-<i>c</i>]pyridines in the Synthesis of Conformationally Restricted Analogues of Nicotine and Anabasine
作者:Tarun K. Sarkar、Sankar Basak、Zdenek Slanina、Tahsin J. Chow
DOI:10.1021/jo026555p
日期:2003.5.1
En route to conformationally restricted analogues of nicotine and anabasine, a novel synthetic route to bridged anabasines is described that hinges on a domino intramolecular [4 + 2]-cycloaddition/ring opening-elimination sequence of 3-amino-substituted furo[3,4-c]pyridines. Extension of this route to bridged nicotines, however, proved abortive, even when the dienophile tether is activated by a p-tolylsulfonyl
在构象受限的尼古丁和金刚烷胺类似物的途径中,描述了一种新的合成的桥接的金刚烷胺合成途径,该途径取决于3-氨基取代的呋喃[3,4]的多米诺骨内分子内[4 + 2]-环加成/开环消除序列。 -c]吡啶。然而,即使将亲二烯体系链通过对甲苯磺酰基基团激活或将二烯部分通过释放电子的甲氧基取代基激活,该途径扩展至桥连的尼古丁也被证明是无效的。进行了详细的密度泛函理论研究(B3LYP / 6-31 + G),以洞悉在前一种情况下促进分子内Diels-Alder反应的因素。