6731-58-4Relevant articles and documents
Formal [3+2] Cycloaddition of Nitrosoallenes with Carbonyl and Nitrile Compounds to Form Functional Cyclic Nitrones
Tanimoto, Hiroki,Shitaoka, Takashi,Yokoyama, Keiichi,Morimoto, Tsumoru,Nishiyama, Yasuhiro,Kakiuchi, Kiyomi
, p. 8722 - 8735 (2016)
The synthesis of functional cyclic nitrones via [3+2] cycloadditions of allenamide-derived nitrosoallenes with carbonyl/nitrile compounds, including ketones, esters, and nitriles, is presented herein. Rapid carbon-carbon, carbon-oxygen, and carbon-nitrogen bond formations were achieved with in situ prepared nitrosoallenes, and densely substituted oxacyclic and carbocyclic nitrones containing tetrasubstituted carbon centers were successfully synthesized. The spirocyclic nitrone products synthesized from cyclic dicarbonyl compounds underwent the unique skeletal rearrangements to cyclic α-ketonitrones.
Catalyst-Free [3 + 3] Annulation/Oxidation of Cyclic Amidines with Activated Olefins: When the Substrate Olefin Is Also an Oxidant
Han, Wendan,Li, Yuanhang,Raveendra Babu, Kaki,Li, Jing,Tang, Yuhai,Wu, Yong,Xu, Silong
supporting information, p. 7832 - 7841 (2021/06/25)
Herein we describe a catalyst-free regioselective [3 + 3] annulation/oxidation reaction of cyclic amidines such as DBU (1,8-diazabicyclo(5.4.0)undec-7-ene) and DBN (1,5-diazabicyclo(4.3.0)non-5-ene) with activated olefins, i.e., 2-arylidenemalononitriles and 2-cyano-3-aryl acrylates, to afford tricyclic 2-pyridones and pyridin-2(1H)-imines, respectively. The mechanism has been proposed based on DFT calculations. In the reaction, the cyclic amidines serve as C,N-bisnucleophiles for the cyclization, while the olefins play a dual role by acting as both reactants and oxidants.
Room Temperature, Reductive Alkylation of Activated Methylene Compounds: Carbon-Carbon Bond Formation Driven by the Rhodium-Catalyzed Water-Gas Shift Reaction
Denmark, Scott E.,Ibrahim, Malek Y. S.,Ambrosi, Andrea
, p. 613 - 630 (2017/06/05)
The rhodium-catalyzed water-gas shift reaction has been demonstrated to drive the reductive alkylation of several classes of activated methylene compounds at room temperature. Under catalysis by rhodium trichloride (2-3 mol %), carbon monoxide (10 bar), water (2-50 equiv), and triethylamine (2.5-7 equiv), the scope has been successfully expanded to cover a wide range of alkylating agents, including aliphatic and aromatic aldehydes, as well as cyclic ketones, in moderate to high yields. This method is comparable to, and for certain aspects, surpasses the established reductive alkylation protocols.