16089-65-9Relevant academic research and scientific papers
Regio- and Enantioselective (3+3) Cycloaddition of Nitrones with 2-Indolylmethanols Enabled by Cooperative Organocatalysis
Li, Tian-Zhen,Liu, Si-Jia,Sun, Yu-Wen,Deng, Shuang,Tan, Wei,Jiao, Yinchun,Zhang, Yu-Chen,Shi, Feng
supporting information, p. 2355 - 2363 (2020/12/09)
The regio- and enantioselective (3+3) cycloaddition of nitrones with 2-indolylmethanols was accomplished by the cooperative catalysis of hexafluoroisopropanol (HFIP) and chiral phosphoric acid (CPA). Using this approach, a series of indole-fused six-membered heterocycles were synthesized in high yields (up to 98 %), with excellent enantioselectivities (up to 96 % ee) and exclusive regiospecificity. This approach enabled not only the first organocatalytic asymmetric (3+3) cycloaddition of nitrones but also the first C3-nucleophilic asymmetric (3+3) cycloaddition of 2-indolylmethanols. More importantly, theoretical calculations elucidated the role of the cocatalyst HFIP in helping CPA control the reactivity and enantioselectivity of the reaction, demonstrating a new mode of cooperative catalysis.
BPh3-Catalyzed [2+3] Cycloaddition of Ph3PCCO with Aldonitrones: Access to 5-Isoxazolidinones with Exocyclic Phosphonium Ylide Moieties
Brar, Amandeep,Unruh, Daniel K.,Ling, Natalie,Krempner, Clemens
, p. 6305 - 6309 (2019/08/20)
A method for the generation of 5-isoxazolidinones with exocyclic phosphonium ylide functionalities via [2+3] cycloaddition of Ph3PCCO and aldonitrones has been developed and applied in the synthesis of 4-alkylidene-5-isoxazolidinones via Wittig olefination. The reaction proceeds by BPh3 catalysis under mild conditions and with a broad substrate scope. A reaction pathway involving the activation of the aldonitrone via interactions with the Lewis acid BPh3 is proposed.
(3 + 3) Cycloaddition of Oxyallyl Cations with Nitrones: Diastereoselective Access to 1,2-Oxazinanes
Cordier, Marie,Archambeau, Alexis
supporting information, p. 2265 - 2268 (2018/04/30)
Oxyallyl cations are prepared in situ from readily available α-tosyloxy ketones and act as transient electrophilic partners in (3 + 3) cycloaddition with nitrones. Under mild conditions, this method provides a chemoselective and diastereoselective route t
One-Pot Sequential [3 + 3] Dipolar Cycloaddition of Aldehyde or Ketone and Hydroxylamine with Spirocyclopropyl Oxindole
Xu, Peng-Wei,Chen, Chen,Liu, Jia-Kuan,Song, Yu-Ting,Zhou, Feng,Yan, Jun,Zhou, Jian
, p. 12763 - 12774 (2018/10/20)
A Sc(OTf)3-catalyzed highly diastereoselective one-pot sequential [3 + 3] dipolar cycloaddition reaction of aldehyde or ketone, N-alkyl hydroxylamine, and spirocyclopropyl oxindole is developed, allowing facile construction of spirocyclic oxind
Cooperative Multifunctional Catalysts for Nitrone Synthesis: Platinum Nanoclusters in Amine-Functionalized Metal–Organic Frameworks
Li, Xinle,Zhang, Biying,Tang, Linlin,Goh, Tian Wei,Qi, Shuyan,Volkov, Alexander,Pei, Yuchen,Qi, Zhiyuan,Tsung, Chia-Kuang,Stanley, Levi,Huang, Wenyu
supporting information, p. 16371 - 16375 (2017/11/28)
Nitrones are key intermediates in organic synthesis and the pharmaceutical industry. The heterogeneous synthesis of nitrones with multifunctional catalysts is extremely attractive but rarely explored. Herein, we report ultrasmall platinum nanoclusters (PtNCs) encapsulated in amine-functionalized Zr metal–organic framework (MOF), UiO-66-NH2 (Pt@UiO-66-NH2) as a multifunctional catalyst in the one-pot tandem synthesis of nitrones. By virtue of the cooperative interplay among the selective hydrogenation activity provided by the ultrasmall PtNCs and Lewis acidity/basicity/nanoconfinement endowed by UiO-66-NH2, Pt@UiO-66-NH2 exhibits remarkable activity and selectivity, in comparison to Pt/carbon, Pt@UiO-66, and Pd@UiO-66-NH2. Pt@UiO-66-NH2 also outperforms Pt nanoparticles supported on the external surface of the same MOF (Pt/UiO-66-NH2). To our knowledge, this work demonstrates the first examples of one-pot synthesis of nitrones using recyclable multifunctional heterogeneous catalysts.
Indium-assisted aluminium-based stereoselective allylation of prostereogenic α,α-disubstituted cycloalkanones and imines
Reddy, Chennakesava,Babu, Srinivasarao Arulananda,Aslam, Nayyar Ahmad
, p. 40199 - 40213 (2014/12/10)
The use of a catalytic amount of InCl3in combination with Al0for the allylation of a variety of prostereogenic α,α-disubstituted (hindered) cycloalkanones, 1,2-dione-based systems and various imino systems (CN functional groups) is reported. The stereoselective InCl3-catalyzed Al-based allylation of various 2-substituted-2-carbethoxycycloalkanones gave the corresponding products with moderate to excellent diastereoselectivity. The allylation and propargylation of imines including α-imino esters using a catalytic amount of InCl3in combination with Al0gave the corresponding allylated and propargylated compounds in moderate to good yields. If γ-substituted allylic halides were added to imino compounds, low to very good diastereoselectivity was obtained. The allylation of chiral N-tert-butylsulfinyl imine systems gave the corresponding products in moderate yields with good to excellent diastereoselectivity. This journal is
1,3-Dipolar cycloadditions. Part-XV: Systematic spectroscopic investigations of C-aryl-N-methylnitrones
Banerji, Avijit,Acharjee, Nivedita,Biswas, Pizush Kanti
scheme or table, p. 63 - 67 (2010/05/02)
Several C-aryl-N-methylnitrones have been synthesised during the course of our work on 1,3-dipolar cycloadditions. Detailed systematic spectroscopic investigations of all these nitrones have been undertaken. These are reported along with some generalisati
1,3-Dipolar cycloadditions: Part VIII1-Microwave irradiation assisted synthesis of N-methyl-C-aryl nitrones
Banerji, Avijit,Biswas, Pizush Kanti,Sengupta, Piyali,Dasgupta, Saugandha,Gupta, Maya
, p. 880 - 881 (2007/10/03)
N-Methyl-C-arylnitrones have been synthesized in very high yields within a few minutes from N-methyl-hydroxylamine hydrochloride and aryl aldehydes in presence of sodium hydrogen carbonate in methylene chloride using the microwave irradiation technique.
Chromium and Tungsten Pentacarbonyl Groups as Reactivity and Selectivity Auxiliaries in Cycloaddition of Alkynyl Fischer Carbene Complexes with N-Alkyl Nitrones
Chan, Kin Shing,Yeung, Ming Lok,Chan, Wai-kin,Wang, Ru-Ji,Mak, Thomas C. W.
, p. 1741 - 1747 (2007/10/02)
Alkynyl Fischer carbene complexes were found to undergo chemoselective, regioselective, and rate-enhanced 1,3-dipolar cycloaddition with nitrones to give 2,3-dihydroisoxazole carbene complexes in excellent yields.These alkynyl complexes can serve as synth
