BF 3 ·CH 3 NO 2介导的多烯级联环化反应。通过非功能化3°烯烃的阳离子引发直接立体定向合成多环中间体的非常规高效方法。在(±)-紫杉二酮的全合成中的应用。
摘要:
BF 3气体在硝基甲烷中的便捷储备溶液已显示出可促进“ H +催化”多烯环化反应,并以极佳的区域和立体控制水平进行。甲直接这种新方法的用于实现阳离子polyannulations若干现代以及经典程序相比,已经结论性地确定的BF的制备优点3 ·CH 3 NO 2平台。描述了这些新条件用于阳离子多环化的简明全合成抗肿瘤药(±)-紫杉二酮。
Alkyldisulfanium Salts: Isolable, Electrophilic Sulfur Reagents Competent for Polyene Cyclizations
作者:Florian T. Schevenels、Minxing Shen、Scott A. Snyder
DOI:10.1021/acs.orglett.6b02059
日期:2017.1.6
sulfur-promoted cation−π cyclizations are generally lacking, especially using alkylsulfide-based reagents. Herein we report that combining three different 1,2-dithioethers with Cl2 and SbCl5 generates isolable alkyldisulfanium salts that can effect such reactions. These new reagents can install −SMe, −SEt, and −SCH2CH2CF3 in modest, moderate, or good yield on diverse frameworks, including polyenes that terminate
Simple Reagents for Direct Halonium-Induced Polyene Cyclizations
作者:Scott A. Snyder、Daniel S. Treitler、Alexandria P. Brucks
DOI:10.1021/ja106813s
日期:2010.10.13
Although there are many reagent combinations that can initiate polyenecyclizations, simple electrophilic halogen sources have not yet proven broadly effective as promoters of such processes. Herein is described a readily prepared and stable class of reagents capable of effecting such transformations for a wide range of electron-rich and -deficient terpenes derived from geraniol, farnesol, and nerol
尽管有许多试剂组合可以引发多烯环化,但尚未证明简单的亲电子卤素源作为此类过程的促进剂广泛有效。本文描述了一类易于制备且稳定的试剂,能够对源自香叶醇、法呢醇和橙花醇的各种富电子和缺电子萜烯进行此类转化,从而能够有效合成多种复杂的氯- 、含溴和含碘的多环骨架。迄今为止的努力已导致抗 HIV 天然产物 Peyssonol A 的第一个外消旋实验室全合成和结构修订,以及 peyssonoic acid A 的有效和简洁的首次全合成。他们还允许正式的外消旋全合成 aplysin- 20、萝莉莉德、K-76、和 Stemodin 将通过通常比以前的努力更短、产量更高且更具环保意识的途径来实现。还描述了使用该试剂类的手性形式进行对映选择性烯烃卤化的初步尝试。
CYCLISATION PROCESS OF FORMING A MULTIPLE RING COMPOUND
申请人:Loh Teck Peng
公开号:US20100228058A1
公开(公告)日:2010-09-09
The present invention relates to a cyclisation process of forming a multiple ring compound from an isoprenoid compound. The cyclisation process involves reacting the isoprenoid compound with an acetal initiator under conditions sufficient to form the multiple ring compound. The isoprenoid compound is contacted with an initiator an optionally with a catalyst. Cyclisation occurs by reaction of the initiator with the isoprenoid compound. Cyclic acetal compounds wherein the acetal forms part of 6-membered unsaturated ring are also defined.
UNIQUE HALOGEN-INDUCED CYCLIZATIONS, REAGENTS THEREFOR, AND COMPOUNDS PRODUCED THEREBY
申请人:Snyder Scott Alan
公开号:US20140243404A1
公开(公告)日:2014-08-28
This disclosure is related to halonium compounds useful for cyclization of polyenes, alkenoic acids, and alkenyl alkyl ethers, and halogenation of aromatic compounds. The synthesis of such halonium compounds, compounds made using such halonium compounds, and synthesis of natural compounds, including decalins, using the halonium compounds is also disclosed. A representative halonium compound of the disclosure is:
[EN] UNIQUE HALOGEN-INDUCED CYCLIZATIONS, REAGENTS THEREFOR, AND COMPOUNDS PRODUCED THEREBY<br/>[FR] CYCLISATIONS PARTICULIÈRES INDUITES PAR HALOGÈNE, RÉACTIFS POUR CELLES-CI ET COMPOSÉS AINSI PRODUITS