在邻吲哚苯胺和重氮化合物之间进行催化剂控制的化学发散环化反应已被研究用于合成吲哚稠合的二氮杂and和喹喔啉。在Rh(III)催化剂下,反应通过游离胺辅助的C2-H活化进行,然后进行酰胺化反应,从而以高度选择性的方式生成重氮庚并[1,7- a ]吲哚。当使用Ru(II)催化剂时,反应涉及形成Ru-卡宾配合物,然后插入-NH 2基团,并通过金属茂型反应进行级联环化,通过β-氢化物消除作用制得吲哚[1,2- a]。以喹喔啉为主要产品。该策略指导模块化方法构建独特的吲哚并结合的二氮杂/喹喔啉以及吡咯并并的二氮杂/喹喔啉骨架,并具有极高的产率。
A highly efficient approach to indolo [1,2-a]quinoxaline derivatives through a Pd-catalyzed regioselective C–Holefination/cyclization sequence has been developed. This transformation has a wide range of substrates with various functional groups, and the corresponding heterocyclic products were obtained in good yields.
已经开发出了一种高效的方法,可通过Pd催化的区域选择性C–H烯化/环化序列制备吲哚[1,2- a ]喹喔啉衍生物。该转化具有多种具有各种官能团的底物,并且以良好的产率获得了相应的杂环产物。
Palladium‐Catalyzed Primary Amine‐Directed Decarboxylative Annulation of
<i>α</i>
‐Oxocarboxylic Acids: Access to Indolo[1,2‐
<i>a</i>
]quinazolines
作者:Guangbin Jiang、Shoucai Wang、Jun Zhang、Jianwen Yu、Ziang Zhang、Fanghua Ji
DOI:10.1002/adsc.201900001
日期:2019.4.16
for the preparation of indolo[1,2‐a]quinazolines via palladium‐catalyzed decarboxylative annulation of indols with α‐oxocarboxylic acids has been realized by using primary amine as a directing group (DG). This transformation proceeds smoothly with exclusive regioselectivity and represents an one‐pot Dominosynthesis of indo‐lo[1,2‐a]quinazolines from α‐oxocarboxylic acids.
用于制备高效的协议吲哚并[1,2一]喹唑啉通过钯-催化的与indols的脱羧环α -oxocarboxylic酸已经通过使用伯胺作为定向基团(DG)实现。这种转化具有排他性区域选择性的顺利进行,代表了从α-氧代羧酸一锅多米诺合成吲哚[1,2- a ]喹唑啉的过程。
Tandem 6π-Azatriene Electrocyclization of Fused Amino-cyclopentenones: Synthesis of Functionalized Pyrrolo- and Indolo-quinoxalines
作者:Kapil Mohan Saini、Rakesh K. Saunthwal、Ankit Kumar、Akhilesh K. Verma
DOI:10.1021/acs.orglett.1c02782
日期:2021.10.1
A tandem 6π-azacyclization approach for the synthesis of diversified pyrrolo/indolo[1,2-a]quinoxalines from amino-cyclopentenones has been developed. The reaction proceeds through a trifluoroacetic-acid-mediated 6π-electrocyclization and concomitant opening of the cyclopentenone ring. The advantageous features of the developed chemistry include transition-metal-free conditions, operational simplicity
已经开发了一种用于从氨基环戊烯酮合成多样化吡咯并/吲哚[1,2- a ]喹喔啉的串联 6π-氮杂环化方法。该反应通过三氟乙酸介导的 6π-电环化和环戊烯酮环的伴随打开进行。所开发化学的优势特征包括无过渡金属条件、操作简单和广泛的底物范围。进一步的 X 射线晶体学研究证实了稠合杂环的指定结构。
Palladium-catalyzed sequential acylation/annulation of indoles with acyl chlorides using primary amine as the directing group
作者:Guangbin Jiang、Guang Yang、Xinqiang Liu、Shoucai Wang、Fanghua Ji
DOI:10.1039/d0nj04406g
日期:——
An attractive and convenient strategy for the direct acylation/annulation of indoles has been developed using Pd(0) as an efficient catalyst. The main feature of this protocol is the use of acyl chlorides as the acylating agents with the primary amine as the directing group. A variety of indolo[1,2-a]quinoxalines were readily obtained in reasonable efficiency and satisfactory yields with good functional
使用Pd(0)作为有效催化剂,已经开发出了一种有吸引力且方便的吲哚直接酰化/环化的策略。该方案的主要特征是使用酰氯作为酰化剂,并以伯胺为导向基团。各种吲哚并[1,2- a ]喹喔啉可以以合理的效率和令人满意的收率获得,并且具有良好的官能团耐受性。在控制实验的基础上,提出了初步的催化机理。