A variety of ketonitrones were synthesized in moderate to excellent yields with high chemo-, regio-, and stereoselectivity by using carbonyl-directed addition of N-alkylhydroxylamines to unactivated alkynes under mild conditions. The product diverisity could be controlled by the use of different bases, and EtN(n-Pr)2 could promote the formation of ketonitrones while using EtONa as base led to indanone-derived
bioinsipred gold‐catalyzed tandem Diels–Alder/Diels–Alderreaction of an enynal and a 1,3‐diene, forming the highly‐strained benzotricyclo[3.2.1.02,7]octane skeleton, was reported. In contrast, a Diels–Alder/Friedel–Crafts tandem reaction occurred instead when silver salts were used as the catalyst. Although both reactions experienced the similar Diels–Alderreaction of a pyrylium intermediate with a
Solvent-Regulated Coupling of 2-Alkynylbenzaldehydes with Cyclic Amines: Selective Synthesis of Fused N-Heterocycles and Functionalized Naphthalene Derivatives
作者:Yan He、Zhi Zheng、Qimeng Liu、Xinying Zhang、Xuesen Fan
DOI:10.1021/acs.orglett.0c03442
日期:2020.11.20
synthesis of 1,2,3,4-tetrahydrobenzo[g]quinoline derivatives through PdCl2-catalyzed, TBHP-promoted, and toluene-mediated dehydrogenation/[4+2] cycloaddition of saturated cyclicamines with 2-alkynylbenzaldehydes was developed. On the contrary, when the reaction medium was changed from toluene to DMSO/H2O, another class of important compounds, naphthyl chain amines, formed via a dehydrogenation–intermolecular
通过PdCl 2催化,TBHP促进和甲苯介导的饱和环胺的脱氢/ [4 + 2]与2-炔基苯甲醛的环加成反应,成功合成了1,2,3,4-四氢苯并[ g ]喹啉衍生物。相反,当反应介质从甲苯变为DMSO / H 2 O时,通过脱氢-分子间缩合-C-N键裂解-分子间缩合途径形成的另一类重要化合物萘链胺选择性好。
Domino Hydroarylation-Cyclization Reaction: One-Pot Synthesis of Indane-Fused 3,4-Dihydrocoumarins
作者:Jin Hyuck Joo、So Won Youn
DOI:10.1002/adsc.201200745
日期:2013.1.9
A tin(II) triflate-catalyzed dominohydroarylation–cyclizationreaction has been developed to access a wide-variety of methyleneindane-fused 3,4-hydrocoumarins. A judiciously selected bi-functional Lewis acidic catalyst has been successfully applied to promote two ring-closing events as a single-pot operation.
Aryne [3 + 2] cycloaddition with N-sulfonylpyridinium imides and in situ generated N-sulfonylisoquinolinium imides: a potential route to pyrido[1,2-b]indazoles and indazolo[3,2-a]isoquinolines
作者:Jingjing Zhao、Pan Li、Chunrui Wu、Hongli Chen、Wenying Ai、Renhong Sun、Hailong Ren、Richard C. Larock、Feng Shi
DOI:10.1039/c2ob06611d
日期:——
The aryne [3 + 2] cycloaddition process with pyridinium imides breaks the aromaticity of the pyridine ring. By equipping the imide nitrogen with a sulfonyl group, the intermediate readily eliminates a sulfinate anion to restore the aromaticity, leading to the formation of pyrido[1,2-b]indazoles. The scope and limitation of this reaction are discussed. As an extension of this chemistry, N-tosylisoquinolinium
与吡啶鎓酰亚胺的芳烃[3 + 2]环加成过程破坏了吡啶环的芳香性。通过在酰亚胺氮上加成磺酰基,该中间体容易消除亚磺酸根阴离子以恢复芳香性,从而导致吡啶并[1,2- b ]吲唑的形成。讨论了该反应的范围和局限性。作为该化学反应的扩展,通过AgOTf催化的6-endo-dig亲电环化反应从N '-(2-炔基亚苄基)-甲苯磺酰肼原位生成的N-甲苯磺酰异喹啉鎓亚胺易于进行芳烃[3 + 2]环加成反应而制得吲哚唑[3,2- a同一锅中的]-异喹啉,为这些潜在的抗癌药提供了高效途径。