190840-83-6Relevant articles and documents
Diels-Alder reactions between hexafluoro-2-butyne and bis-furyl dienes: Kinetic: versus thermodynamic control
Borisova, Kseniya K.,Nikitina, Eugeniya V.,Novikov, Roman A.,Khrustalev, Victor N.,Dorovatovskii, Pavel V.,Zubavichus, Yan V.,Kuznetsov, Maxim L.,Zaytsev, Vladimir P.,Varlamov, Alexey V.,Zubkov, Fedor I.
, p. 2850 - 2853 (2018)
The tandem [4+2] cycloaddition between hexafluoro-2-butyne and bis-furyl dienes, like difurfuryl ester, at room temperature leads to the kinetically controlled pincer -adducts-annulated 4a,8a-bis(trifluoromethyl)hexahydro-1,4:5,8-diepoxynaphthalenes. On the other hand, if these reactions proceed at 140 °C, only the thermodynamically controlled domino -adducts-annulated 2,3-bis(trifluoromethyl)hexahydro-1,4:5,8-diepoxynaphthalenes-are formed. Therefore, a very rare and unexpected example of full kinetic and thermodynamic control in the Diels-Alder reaction is reported in this paper.
Classical Example of Total Kinetic and Thermodynamic Control: The Diels-Alder Reaction between DMAD and Bis-furyl Dienes
Borisova, Kseniya K.,Kvyatkovskaya, Elizaveta A.,Nikitina, Eugeniya V.,Aysin, Rinat R.,Novikov, Roman A.,Zubkov, Fedor I.
, p. 4840 - 4850 (2018)
A rare example of chemospecificity in the tandem Diels-Alder reaction of activated alkynes and bis-dienes has been revealed. The reaction between bis-furyl dienes and DMAD occurs at 25-80 °C and leads to kinetically controlled pincer adducts, 4a,8a-disubstituted 1,4:5,8-diepoxynaphthalenes. On the contrary, only thermodynamically controlled domino adducts (2,3-disubstituted 1,4:5,8-diepoxynaphthalenes) are formed in the same reaction at 140 °C. The pincer adducts can be transformed to the domino adducts at heating. The rate constants for reactions of both types were calculated using dynamic 1H NMR spectroscopy.
Simplified preparation of a graphene-co-shelled Ni/NiO@C nano-catalyst and its application in theN-dimethylation synthesis of amines under mild conditions
Liu, Jianguo,Ma, Longlong,Song, Yanpei,Zhang, Mingyue,Zhuang, Xiuzheng
, p. 4604 - 4617 (2021/06/30)
The development of Earth-abundant, reusable and non-toxic heterogeneous catalysts to be applied in the pharmaceutical industry for bio-active relevant compound synthesis remains an important goal of general chemical research.N-methylated compounds, as one of the most essential bioactive compounds, have been widely used in the fine and bulk chemical industries for the production of high-value chemicals. Herein, an environmentally friendly and simplified method for the preparation of graphene encapsulated Ni/NiO nanoalloy catalysts (Ni/NiO@C) was developed for the first time, for the highly selective synthesis ofN-methylated compounds using various functional amines and aldehydes under easy to handle, and industrially applicable conditions. A large number of primary and secondary amines (more than 70 examples) could be converted to the correspondingN,N-dimethylamines with the participation of different functional aldehydes, with an average yield of over 95%. A gram-scale synthesis also demonstrated a similar yield when compared with the benchmark test. In addition, it was further proved that the catalyst could easily be recycled because of its intrinsic magnetism and reused up to 10 times without losing its activity and selectivity. Also, for the first time, the tandem synthesis ofN,N-dimethylamine products in a one-pot process, using only a single earth-abundant metal catalyst, whose activity and selectivity were more than 99% and 94%, respectively, for all tested substrates, was developed. Overall, the advantages of this newly developed method include operational simplicity, high stability, easy recyclability, cost-effectiveness of the catalyst, and good functional group compatibility for the synthesis ofN-methylation products as well as the industrially applicable tandem synthesis process.
An Expedient Route for the Stereoselective Construction of Bridged Polyheterocyclic Ring Systems Using the Tandem "Pincer" Diels-Alder Reaction
Lautens, Mark,Fillion, Eric
, p. 4418 - 4427 (2007/10/03)
The tandem "pincer" Diels-Alder reaction, consisting of two consecutive [4 + 2] cycloadditions between two dienes and an acetylenic bis-dienophile, has been applied toward the rapid construction of bridged polyoxacyclic ring systems when furan derivatives are used as the diene components. The study has demonstrated the stereoselectivity (exo-exo adduct), the chemoselectivity ("pincer" vs "domino"), as well as the regioselectivity of the reaction. The reaction has been successfully applied to a variety of 2-substituted furans and tethered bis-furans in combination with mono-activated and diactivated dienophiles. The synthesis of unsymmetrical cycloadducts starting from the aza- and oxanorbornadiene-type intermediate has also been realized.
