An Imine-Based Route to Polycyclic Chlorinated ε-Lactams by Formation of C–C Bonds as Key Steps
摘要:
A two-step sequence for the conversion of heterocyclic imines to saturated and unsaturated polycyclic chlorinated epsilon-lactams is disclosed. In the first step, an acyl chloride addition followed by a substitution is used to achieve unsaturated methoxyamides. The final lactamization to two different classes of polycyclic epsilon-lactams via formation of a C-C bond is realized by the use of metal chlorides as Lewis acid and as a source of chloride. The potential of the epsilon-lactams in subsequent reactions is demonstrated by an elimination reaction.
A new three‐step synthetic pathway to generate polycyclicannulated hydantoins via rarely investigated heterocyclic imines is described. This procedure includes a one‐pot reaction forming imines as precursor structures (e.g., Asinger reaction), followed by an Ugi reaction to build up a bisamide structure that allows a ring‐closing reaction to the targeted hydantoins via substitution. This pathway leads
Stereospecific Synthesis of β-Lactams from Heterocyclic Imines Using the Staudinger Reaction
作者:T. Stalling、K. Johannes、S. Polina、J. Martens
DOI:10.1002/jhet.1688
日期:2013.5
The reactions of the heterocyclicimines 5,6‐dihydro‐2H‐[1,3]oxazines and 2H‐1,4‐benzothiazines with different substituted acetyl chlorides in the presence of triethylamine forming β‐lactams were examined focusing on the stereochemistry of the Staudingerreaction.
在形成三乙胺的β-内酰胺存在下,研究了杂环亚胺5,6-二氢-2 H- [1,3]恶嗪和2 H -1,4-苯并噻嗪与不同取代的乙酰氯的反应施陶丁格反应的过程。
Three-Component Reaction toward Polyannulated Quinazolinones, Benzoxazinones, and Benzothiazinones
take part in nucleophilic aromatic substitution (SNAr) reactions is realized in a new three-component, one-pot reaction, giving at least tricyclic annulated quinazolinones, benzoxazinones, and benzothiazinones as a result of the employed nitrogen, oxygen, or sulfur nucleophiles, respectively. Especially in the case of quinazolinones, this convenient strategy enables the access to heterocycles of heightened
在新的三组分一锅法反应中,实现了易于参与的环状亚胺与酰基氯的有效转化,该亚胺能够参与亲核芳香族取代(S N Ar)反应,至少产生三环环化喹唑啉酮,苯并恶嗪酮分别是由于使用了氮,氧或硫亲核试剂而产生的苯并噻嗪酮。特别是在喹唑啉酮的情况下,这种方便的策略使人们能够进入多样性更高的杂环,这为精细杂环骨架的有效衍生化提供了发展。在随后的Heck或Ullmann环化中,可以对所提及的喹唑啉酮进行进一步的环合。
Rearrangement in the Synthesis of Annulated Lactams Starting from Benzothiazines
作者:Timo Stalling、Wolfgang Saak、Jürgen Martens
DOI:10.1002/ejoc.201300768
日期:2013.10
the one hand, different types of unknown lactam systems with and without a rearrangement under ring contraction of the benzothiazine substructure were selectively obtained. In this investigation, annulated lactams without ring contraction were formed by oxidation of the sulfide group to a sulfone group in the benzothiazine skeleton. On the other hand, benzothiazoles, which are oxidation products, were
基于亚胺 1,4-苯并噻嗪的甲氧基酰胺的转化根据取代模式产生了三种不同的产品。一方面,选择性地获得了不同类型的未知内酰胺体系,在苯并噻嗪亚结构的环收缩下有和没有重排。在这项研究中,没有环收缩的环状内酰胺是通过将硫化物基团氧化成苯并噻嗪骨架中的砜基团而形成的。另一方面,分离出氧化产物苯并噻唑。所有类型内酰胺的结构均通过 X 射线衍射验证。
A highly enantioselective catalytic Strecker reaction of cyclic (Z)-aldimines
作者:You-Dong Shao、Shi-Kai Tian
DOI:10.1039/c2cc31001e
日期:——
A range of 3H-indoles and 2H-benzo[b][1,4]thiazines smoothly undergo asymmetric Strecker reaction with ethyl cyanoformate in the presence of a Cinchona alkaloid-based thiourea catalyst at 10 °C to give structurally diverse nitrogen-containing heterocycles in good to excellent yields and with excellent ee.