Exploiting the Electrophilic and Nucleophilic Dual Role of Nitrile Imines: One-Pot, Three-Component Synthesis of Furo[2,3-d]pyridazin-4(5H)-ones
摘要:
An expeditious multicomponent reaction to synthesize tetrasubstituted furo[2,3-d]pyridazin-4(5H)-ones is reported. In brief, hydrazonoyl chlorides react with isocyanoacetamides, in the presence of TEA, to give 1,3-oxazol-2-hydrazones which, without being isolated, can react with dimethylacetylene dicarboxylate to afford furo[2,3-d]pyridazin-4(5H)-ones with an unprecedented level of complexity in a triple domino Diels-Alder/retro-Diels-Alder/lactamization reaction sequence.
Silver‐Catalyzed Sequential Cascade Reaction of Isocyanides with 1‐(2‐Ethynyl‐phenyl)‐prop‐2‐yn‐1‐ol: Access to Benzo[
<i>b</i>
]fluorenes and Benzofuran‐Pyrroles
作者:Jian‐Quan Liu、Xinyi Chen、Xuanyu Shen、Yihan Wang、Xiang‐Shan Wang、Xihe Bi
DOI:10.1002/adsc.201801344
日期:2019.4
A silver‐catalyzed cycloaromatization of 1‐(2‐ethynyl‐phenyl)‐prop‐2‐yn‐1‐ol with isocyanides efficiently provides benzo[b]fluorene and benzofuran‐pyrrole derivatives through a modular cascade reaction that includes a nucleophilic attack on the diyne substrate. A C−C cross‐coupling/oxygen transportation/Diels‐Alder/hydrogen shift/isomerization cascade mechanistic pathway is proposed.
银与异氰酸酯催化的1-(2-乙炔基-苯基)-丙-2-炔-1-醇的芳环芳香化反应可通过模块级联反应有效地提供苯并[ b ]芴和苯并呋喃-吡咯衍生物,包括对苯并的亲核攻击。二炔底物。提出了AC-C交叉偶联/氧迁移/ Diels-Alder /氢转移/异构化级联机制途径。
Synthesis of Oxazolidin-2-ones by Oxidative Coupling of Isonitriles, Phenyl Vinyl Selenone, and Water
unprecedented heteroannulation process created four chemical bonds in a single operation with the isocyano group acting formally as a polarized double bond and phenyl vinyl selenone as a latent 1,3‐dipole. The phenylselenonyl group played a triple role as an electron‐withdrawing group to activate the 1,4‐addition, a leaving group, and a latent oxidant in this transformation.
在催化量的Cs 2 CO 3存在下,烷基异氰化物,苯基乙烯基硒酮和水的反应得到了恶唑烷-2-酮,收率很高。这种空前的异环化过程在一次操作中产生了四个化学键,异氰基在形式上起极化双键作用,苯基乙烯基硒酮起潜在的1,3-偶极作用。苯基硒壬基在该转化过程中作为吸电子基团发挥了三重作用,以激活1,4加成,一个离去基团和一个潜在的氧化剂。
1,6-Addition Arylation of para-Quinone Methides: An Approach to Unsymmetrical Triarylmethanes
作者:Shang Gao、Xiuyan Xu、Zhenbo Yuan、Haipin Zhou、Hequan Yao、Aijun Lin
DOI:10.1002/ejoc.201600385
日期:2016.6
A 1,6-addition arylation reaction of para-quinone methides with α-isocyanoacetamides and electron-rich aromatic compounds under metal-free conditions has been developed. BF3·Et2O plays two roles in the reaction: catalyzing the cyclization of α-isocyanoacetamides to give oxazoles, and activating the para-quinone methides to achieve the 1,6-addition arylation process. The reaction shows good functional
The synthesis of N‐acylurea derivatives through the silver‐catalyzed coupling of readily available dioxazolones with isocyanides and water has been reported. The desired products were obtained in moderate to good yields. The reaction can be performed on gram scale. The 18O‐labelling experiment shows that water participates in this reaction. A possible reactionmechanism is proposed in which carbodiimide
Synthesis of Pyrroles by Consecutive Multicomponent Reaction/[4 + 1] Cycloaddition of α-Iminonitriles with Isocyanides
作者:Patrice Fontaine、Géraldine Masson、Jieping Zhu
DOI:10.1021/ol9001619
日期:2009.4.2
[4 + 1] Cycloaddition of α,β-unsaturated imidoyl cyanide (2-cyano-1-azadienes) with isocyanides in the presence of a catalytic amount of AlCl3 afforded polysubstituted 2-amino-5-cyanopyrroles in good to excellent yields. In combination with the IBX/TBAB-mediated oxidative Strecker reaction, this important heterocycle is readily synthesized in two steps from simple starting materials.