骨架编辑是一种简单的合成策略,用于精确替换或重排复杂分子核心环结构中的原子;它可以实现化合物的快速多样化,这是通过应用外围编辑策略不可能实现的。先前报道的常见芳烃的骨架编辑主要依赖于卡宾或氮宾类型的插入反应或重排。尽管这些策略功能强大、高效且适用于后期杂芳烃核心结构修饰,但不能用于吡啶的骨架编辑。在这里,我们报告了通过从 CN 到 CC 的原子对交换对吡啶进行直接骨架编辑,以模块化方式生成苯和萘。具体来说,我们在一锅序列中使用顺序脱芳构化、环加成和再芳构化逆环加成反应,将母体吡啶转化为在特定位点带有多种取代基的苯和萘,这些取代基由环加成反应组分定义。证明了吡啶核心在多种药物中的后期骨骼多样化中的应用。
Isothiourea-Mediated One-Pot Synthesis of Trifluoromethyl Substituted 2-Pyrones
作者:Pei-Pei Yeh、David S. B. Daniels、David B. Cordes、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/ol403697h
日期:2014.2.7
A one-potisothiourea-mediated Michael addition/lactonization/thiol elimination cascade sequence for the formation of 4,6-disubstituted and 3,4,6-trisubstituted 2-pyrones from (phenylthio)acetic acids and α,β-unsaturated trifluoromethyl ketones is described. The synthesis of a COX-2 inhibitor and the wide-ranging derivatization of the 2-pyrone moiety to trifluoromethyl substituted aromatics and heteroaromatics
Anionic Amino-Cope Rearrangement Cascade Synthesis of 2,4-Substituted Benzoate Esters from Acyclic Building Blocks
作者:M. Haziq Qureshi、Jon T. Njardarson
DOI:10.1021/acs.orglett.2c03134
日期:2022.11.4
We report a new anionic cascade for assembling 2,4-substituted benzoate esters in one pot from racemic β-fluoro-substituted conjugated tert-butylsulfinyl imines and 3-substituted methyl 2-butenoates. Dienolate formation triggers a Mannich addition followed by an amino-Cope like rearrangement, which results in immediate elimination of fluoride by a lithiated enamine. The newly formed 1,4-diene intermediate