Rhodium-Catalyzed Cyclization of Diynes with Nitrones: A Formal [2+2+5] Approach to Bridged Eight-Membered Heterocycles
作者:Chunxiang Wang、Dongping Wang、Hao Yan、Haolong Wang、Bin Pan、Xiaoyi Xin、Xincheng Li、Fan Wu、Boshun Wan
DOI:10.1002/anie.201407394
日期:2014.10.27
N‐aryl‐substituted nitrones were employed as five‐atom couplingpartners in the rhodium‐catalyzed cyclization with diynes. In this reaction, the nitrone moiety served as a directing group for the catalytic CHactivation of the N‐aryl ring. This formal [2+2+5] approach allows rapid access to bridged eight‐membered heterocycles with broad substrate scope. The results of this study may provide new insight
An Efficient Deoxygenation of Nitrones and Heteroarene N-Oxides†
作者:Dilip K. Dutta、Dilip Konwar
DOI:10.1039/a708471d
日期:——
Selective deoxygenation of nitrones and heteroarene N-oxides with the ZnâAlCl3·6H2O-THF system produces the corresponding imines and heteroarenes in high yield.
One-Pot Enol Silane Formation/Mukaiyama-Mannich Addition of Ketones, Amides, and Thioesters to Nitrones in the Presence of Trialkylsilyl Trifluoromethanesulfonates
作者:C. Wade Downey、Carolyn M. Dombrowski、Erin N. Maxwell、Chelsea L. Safran、Odamea A. Akomah
DOI:10.1002/ejoc.201300691
日期:2013.9
Ketones, amides, and thioesters form enolsilanes and add to N-phenylnitrones in one pot in the presence of trimethylsilyl trifluoromethanesulfonate and trialkylamine. The reaction is general to a range of silyl trifluoromethanesulfonates and N-phenylnitrones. The β-(silyloxy)amino carbonyl products are stable to chromatography and can be isolated in 63–99 % yield.
AlCl3 · 6 H2O/KI/CH3CN/H2O System: An Efficient General System for Deoxygenation of Organic N-Oxides in Hydrated Media
作者:Monalisa Boruah、Dilip Konwar
DOI:10.1055/s-2001-14617
日期:——
An efficient general system for deoxygenation of organic N-oxides such as N-aryl nitrones, azoxy benzenes and N-heteroarene N-oxides uses AlCl3 · 6 H2O/KI/CH3CN/H2O system at room temperature in hydrated media. The deoxygenated products were found in good yields.
Gold-Catalyzed Oxidative Arylations of 3-Butyn-1-ols and 2-Propyn-1-ols with Nitrones to Yield Distinct Fused Indoles Bearing a Heterocyclic Ring
作者:Rajkumar Lalji Sahani、Rai-Shung Liu
DOI:10.1021/acscatal.9b01491
日期:2019.7.5
The catalytic formation of various fused indoles from the nitrone oxidations of 1-substituted n-yn-1-ols (n = 2, 3) is described. For 3-butyn-1-ols, the oxidations yield tetrahydropyrano[4,3-b]indoles, whereas 2-propynols deliver tetrahydro-[1,2]oxazino[5,4-b]indoles efficiently. When styryl nitrones were tested on 2-propyn-1-ols, dihydrooxazolo[3,4-a]indoles were produced efficiently. We postulate
描述了由1-取代的n -yn-1-ols(n = 2,3)的硝酮氧化催化形成各种稠合吲哚的方法。对于3-丁炔-1-醇,氧化产生四氢吡喃并[4,3- b ]吲哚,而2-丙炔醇有效地递送四氢-[1,2]恶嗪基[5,4- b ]吲哚。当在2-丙炔-1-醇上测试苯乙烯基硝酮时,可以高效地生产二氢恶唑并[3,4- a ]吲哚。我们假定这些稠合的吲哚的形成是由共同的机理引起的,该机制涉及在这些稠合的吲哚之前,初始的烯基金中间体的[3,3]-σ位移以提供羰基化作用。