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Search for "cascade reactions" in Full Text gives 82 result(s) in Beilstein Journal of Organic Chemistry.

Stereoselective amine-thiourea-catalysed sulfa-Michael/nitroaldol cascade approach to 3,4,5-substituted tetrahydrothiophenes bearing a quaternary stereocenter

  • Sara Meninno,
  • Chiara Volpe,
  • Giorgio Della Sala,
  • Amedeo Capobianco and
  • Alessandra Lattanzi

Beilstein J. Org. Chem. 2016, 12, 643–647, doi:10.3762/bjoc.12.63

Graphical Abstract
  • obtain this class of compounds and only recently organocatalytic stereoselective cascade reactions have emerged as the most successful, and straightforward approach to access them [7][8]. Aminocatalytic [9][10][11][12] and non-covalent organocatalytic cascade sulfa-Michael/Michael [13][14][15] and sulfa
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Published 05 Apr 2016

Art, auto-mechanics, and supramolecular chemistry. A merging of hobbies and career

  • Eric V. Anslyn

Beilstein J. Org. Chem. 2016, 12, 362–376, doi:10.3762/bjoc.12.40

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  • cascade reactions, for signal amplification purposes. Given their advances, we are currently using our own physical organic chemistry insights to amplify the responses of molecular recognition in single analyte or array sensing. This is an area where supramolecular and physical organic chemists can create
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Published 26 Feb 2016

A quadruple cascade protocol for the one-pot synthesis of fully-substituted hexahydroisoindolinones from simple substrates

  • Hong-Bo Zhang,
  • Yong-Chun Luo,
  • Xiu-Qin Hu,
  • Yong-Min Liang and
  • Peng-Fei Xu

Beilstein J. Org. Chem. 2016, 12, 253–259, doi:10.3762/bjoc.12.27

Graphical Abstract
  • carboxylic acid anhydrides, respectively [17]. To the best of our knowledge, no efficient method toward the synthesis of fully-substituted hexahydroisoindolinones has been developed so far. The synthesis of complicated molecular structures can now be achieved by organocatalytic cascade reactions [18][19][20
  • generated through multicomponent quadruple cascade reactions, there is no report about the cascade synthesis of isoindolines in the past few decades [35][36][37][38][39][40][41][42][43][44][45][46], not mention the quadruple cascade synthesis of difficult fully-substituted hexahydroisoindolinones
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Published 11 Feb 2016

Bifunctional phase-transfer catalysis in the asymmetric synthesis of biologically active isoindolinones

  • Antonia Di Mola,
  • Maximilian Tiffner,
  • Francesco Scorzelli,
  • Laura Palombi,
  • Rosanna Filosa,
  • Paolo De Caprariis,
  • Mario Waser and
  • Antonio Massa

Beilstein J. Org. Chem. 2015, 11, 2591–2599, doi:10.3762/bjoc.11.279

Graphical Abstract
  • particularly promising for large scale applications. Keywords: asymmetric synthesis; Belliotti (S)-PD 172938; heterocycles; isoindolinones cascade reactions; phase transfer catalysts; Introduction Among the nitrogen heterocycles, the isoindolinone ring system is a favored scaffold, owing to the wide range of
  • , illustrating the need for more convenient strategies for large scale applications [4][5][6][7][8]. Recently, cascade reactions have received increasing attention due to the possibility of construction of complex scaffolds in operationally simple, one-pot procedures, starting from readily available materials
  • isoindolinones 9 via retro-Michael process. Asymmetric synthesis of (S)-PD172938. Coupling of chiral acid 9 with p-tolylpiperazine and CuI arylation of chiral isoindolinones. Catalyst screening in asymmetric cascade reactions of 2-cyanobenzaldehyde. Optimization of the asymmetric cascade reaction. Optimization
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Published 15 Dec 2015

Recent advances in copper-catalyzed C–H bond amidation

  • Jie-Ping Wan and
  • Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

Graphical Abstract
  • copper catalysis is in the C–N bond formation by using carbon sources and nitrogen functional groups such as amides. In this review, the recent progress in the amidation reactions employing copper-catalyzed C–H amidation is summarized. Keywords: amidation; C–H bond; cascade reactions; Copper catalysis
  • sulfonamidation and imidation) reactions under the categories of C(sp3)–H bond amidation, C(sp2)–H bond amidation, C(sp)–H bond amidation and cascade reactions initiated by C–H amidation. Review C(sp3)–H bond amidation Intermolecular amidation The formation of N-alkylamides could be traditionally accessed via
  • also get aminated by using secondary amines such as diphenylamine. C–H bond amidation in cascade reactions The success of these different kinds of C–H amidation reactions, as aforementioned, enabled the facile synthesis of diverse secondary or tertiary amides by installing a new chemical motif to the
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Published 17 Nov 2015

C–H bond halogenation catalyzed or mediated by copper: an overview

  • Wenyan Hao and
  • Yunyun Liu

Beilstein J. Org. Chem. 2015, 11, 2132–2144, doi:10.3762/bjoc.11.230

Graphical Abstract
  • –X containing compounds. Recently, Zhu and co-workers reported a new approach for the synthesis of 2 or 4-iododibenzofurans based on CuI-mediated cascade reactions wherein the C–H iodination and cycloetherification acted as key transformations [55]. As outlined in Scheme 15, in the presence of 1.5
  • (Scheme 18). Rather recently, Liu and co-workers [62] reported an alternative approach to the synthesis of 3-brominated indolizines via copper-catalyzed three-component cascade reactions of pyridines 56, α-bromoketones 57 and maleic anhydride (58). The construction of the products involved in the three
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Published 09 Nov 2015

Gold-catalyzed formation of pyrrolo- and indolo-oxazin-1-one derivatives: The key structure of some marine natural products

  • Sultan Taskaya,
  • Nurettin Menges and
  • Metin Balci

Beilstein J. Org. Chem. 2015, 11, 897–905, doi:10.3762/bjoc.11.101

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  • hemiacetals after cascade reactions. Keywords: alkyne cyclization; gold-catalyzed reaction; indolo-oxazin-1-one; marine natural products; pyrrolo-oxazin-1-one; Introduction Pyrrole-containing heterocycles are widely distributed within a large number of natural products and biologically active molecules [1
  • -one derivatives. Some of the exo-cyclic double bonds underwent isomerization to endo-cyclic compounds upon treatment with TFA, while some did not. DFT studies supported our findings. Moreover, cyclization reactions in the presence of alcohol formed hemiacetal derivatives after gold-catalyzed cascade
  • reactions. Structures of some marine natural products 1–4. Structures 5–7. Geometry optimized structures of 6, 7, 30 and 31. Intramolecular gold(I)-catalyzed cyclization reaction of 8 to give 9 and 10. Synthesis of 13 and its reaction with AuCl3. Synthesis of 6. Reaction of 15 with Au(I)/AgOTf in the
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Published 28 May 2015

Further exploration of the heterocyclic diversity accessible from the allylation chemistry of indigo

  • Alireza Shakoori,
  • John B. Bremner,
  • Mohammed K. Abdel-Hamid,
  • Anthony C. Willis,
  • Rachada Haritakun and
  • Paul A. Keller

Beilstein J. Org. Chem. 2015, 11, 481–492, doi:10.3762/bjoc.11.54

Graphical Abstract
  • -closing metathesis of the N,O-diallylic spiro structure and subsequent Claisen rearrangement gave rise to the new (1R,8aS,17aS)-rel-1,2-dihydro-1-vinyl-8H,17H,9H-benz[2',3']pyrrolizino[1',7a':2,3]pyrido[1,2-a]indole-8,17-(2H,9H)-dione heterocyclic system. Keywords: allylation; cascade reactions; indigo
  • explored is to take cheap and readily available structurally advanced starting materials and induce cascade reactions to produce relatively complex heterocycles. For example, initial exploratory studies on the base-induced N-alkylation chemistry of readily available indigo (1) with functionalised alkyl
  • , and to assess other products produced, including any new heterocyclic systems produced. Therefore, this manuscript describes procedures for the highly controlled one-pot cascade reactions of indigo with variations of the allylic bromides used and reaction times. The outcomes included the synthesis of
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Published 15 Apr 2015

Copper-catalyzed cascade reactions of α,β-unsaturated esters with keto esters

  • Zhengning Li,
  • Chongnian Wang and
  • Zengchang Li

Beilstein J. Org. Chem. 2015, 11, 213–218, doi:10.3762/bjoc.11.23

Graphical Abstract
  • of γ-carboxy-γ-lactones via a copper-catalyzed cascade reaction. Considering that the reported conjugate addition–aldolization–lactonization cascade reactions proceed via the key intermediate A in Figure 1, we envisioned that the conjugate reduction of a methacrylate and the following aldol reaction
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Published 06 Feb 2015

Multicomponent reactions in nucleoside chemistry

  • Mariola Koszytkowska-Stawińska and
  • Włodzimierz Buchowicz

Beilstein J. Org. Chem. 2014, 10, 1706–1732, doi:10.3762/bjoc.10.179

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  • rationalized using semi-empirical calculations. In the same contribution, the cascade reactions starting from uracil polyoxin C 106 were described (Scheme 44). Decarboxylative formation of azomethine ylides from 106 and an aldehyde (or ketone), followed by reaction of the ylide with maleimide afforded mixtures
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Published 29 Jul 2014

Cyclization–endoperoxidation cascade reactions of dienes mediated by a pyrylium photoredox catalyst

  • Nathan J. Gesmundo and
  • David A. Nicewicz

Beilstein J. Org. Chem. 2014, 10, 1272–1281, doi:10.3762/bjoc.10.128

Graphical Abstract
  • hydroperoxides with pendant alkenes or alkynes have been developed. Selected examples include Pd(II)-catalyzed hydroalkoxylation reactions of unsaturated hydroperoxides [9], Au(I)-catalyzed endoperoxidation of alkynes [10] and Brønsted acid-catalyzed enantioselective acetalization/oxa-Michael addition cascade
  • reactions of peroxyquinols [11]. While these extant methods are effective at installing the endoperoxide functional group, our interest lay in developing strategies that simultaneously forged both the cyclic peroxide as well as the carbon framework to rapidly build molecular complexity. For this reason, we
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Published 03 Jun 2014

Silver and gold-catalyzed multicomponent reactions

  • Giorgio Abbiati and
  • Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

Graphical Abstract
  • performed in water at 60 °C starting from indolecarboxaldehydes 10, phenyl- and trimethylsilylacetylenes and cyclic/acyclic secondary amines, with the reaction yields ranging from fair to excellent (Scheme 10). Two elegant examples of cascade reactions involving an A3-MCR for the synthesis of valuable
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Published 26 Feb 2014

Microwave-assisted synthesis of 5,6-dihydroindolo[1,2-a]quinoxaline derivatives through copper-catalyzed intramolecular N-arylation

  • Fei Zhao,
  • Lei Zhang,
  • Hailong Liu,
  • Shengbin Zhou and
  • Hong Liu

Beilstein J. Org. Chem. 2013, 9, 2463–2469, doi:10.3762/bjoc.9.285

Graphical Abstract
  • approaches toward the synthesis of 5,6-dihydroindolo[1,2-a]quinoxaline derivatives have been reported [29][30][31][32][33][34][35][36][37][38][39][40][41][42]: (a) Ru- and Au-catalyzed cascade reactions between 2-(1H-indol-1-yl)anilines and alkynes [34][42]. (b) AlCl3-catalyzed Pictet–Spengler reactions
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Published 14 Nov 2013

AgOTf-catalyzed one-pot reactions of 2-alkynylbenzaldoximes with α,β-unsaturated carbonyl compounds

  • Qiuping Ding,
  • Dan Wang,
  • Puying Luo,
  • Meiling Liu,
  • Shouzhi Pu and
  • Liyun Zhou

Beilstein J. Org. Chem. 2013, 9, 1949–1956, doi:10.3762/bjoc.9.231

Graphical Abstract
  • excellent yields. Keywords: 2-alkynylbenzaldoxime; cyclization; 2-(isoquinolin-1-yl)ethanol; rearrangement; α,β-unsaturated carbonyl compound; Introduction One-pot combinations of multi-catalysis and multi-component cascade reactions [1][2][3][4][5][6], in which several bond-forming steps take place in a
  • -workers also reported many other highly functionalized isoquinoline derivatives by cascade reactions in good yields under mild conditions, such as 1-aminoisoquinolines [37] and 1-(isoquinolin-1-yl)ureas [38][39]. Recently, Deng and co-workers also described a new Pd-catalyzed C–H oxidation system for the
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Published 27 Sep 2013

Gold-catalyzed cyclization of allenyl acetal derivatives

  • Dhananjayan Vasu,
  • Samir Kundlik Pawar and
  • Rai-Shung Liu

Beilstein J. Org. Chem. 2013, 9, 1751–1756, doi:10.3762/bjoc.9.202

Graphical Abstract
  • oxacyclic frameworks. Such cascade reactions have been well studied on various difunctionalized molecules including oxoalkynes [6][7][8][9][10][11][12][13], oxoallenes [14], oxoalkenes [15] and allenyl acetals [16][17][18]. In this cascade sequence, two new rings and three chemical bonds are generated in a
  • %), which was shown to be an active catalyst in the two cascade reactions, as depicted in Scheme 1 [17][18]. As shown in Table 1, the treatment of compound 1a with this gold catalyst (5 mol %) in dichloromethane (DCM, 28 °C, 0.5 h) afforded 5-isopropylidenecyclopent-2-en-1-one derivative 4a in 65% yield
  • reduced pressure. The crude product was purified by flash chromatography to afford the desired ketone 6a (58 mg, 0.25 mmol, 76%) as a dark yellow oil. Reported cascade reactions on allenyl acetals. Gold-catalyzed cyclization of deuterated d1-1a. A plausible reaction mechanism. The reaction of propargyl
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Published 27 Aug 2013

Practical synthesis of indoles and benzofurans in water using a heterogeneous bimetallic catalyst

  • Cybille Rossy,
  • Eric Fouquet and
  • François-Xavier Felpin

Beilstein J. Org. Chem. 2013, 9, 1426–1431, doi:10.3762/bjoc.9.160

Graphical Abstract
  • , including benzylic ones, was observed with this catalytic system, highlighting the versatility of our heterogeneous bimetallic catalytic system. This methodology using a homemade Pd–Cu/C catalyst is one of the rare examples of a multitask heterogeneous bimetallic catalysis for tandem or cascade reactions
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Published 16 Jul 2013

Anionic cascade reactions. One-pot assembly of (Z)-chloro-exo-methylenetetrahydrofurans from β-hydroxyketones

  • István E. Markó and
  • Florian T. Schevenels

Beilstein J. Org. Chem. 2013, 9, 1319–1325, doi:10.3762/bjoc.9.148

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Published 03 Jul 2013

Catalytic asymmetric tandem Friedel–Crafts alkylation/Michael addition reaction for the synthesis of highly functionalized chromans

  • Jiahuan Peng and
  • Da-Ming Du

Beilstein J. Org. Chem. 2013, 9, 1210–1216, doi:10.3762/bjoc.9.137

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  • reaction; Introduction The development of efficient and convenient methods to access complex compounds with multiple stereogenic centers is one of the significant challenges in organic chemistry. Catalytic asymmetric tandem or cascade reactions are powerful tools to afford complex molecules with multiple
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Published 24 Jun 2013

Aqueous reductive amination using a dendritic metal catalyst in a dialysis bag

  • Jorgen S. Willemsen,
  • Jan C. M. van Hest and
  • Floris P. J. T. Rutjes

Beilstein J. Org. Chem. 2013, 9, 960–965, doi:10.3762/bjoc.9.110

Graphical Abstract
  • unfriendly solvents. As part of a research program, in which we focus on conducting cascade reactions catalyzed by the joint action of organometallic catalysts and enzymes, we studied possibilities to compartmentalize metal catalysts in an aqueous environment. Inspired by the aforementioned dendrimer
  • , the G4 catalyst 17 was equally active in a second run, clearly demonstrating the viability of containment of the catalyst in the dialysis bag. This result also suggests that the immobilized catalyst should be applicable in cascade reactions with reagents that are normally incompatible with the iridium
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Published 17 May 2013

Synthesis of skeletally diverse alkaloid-like molecules: exploitation of metathesis substrates assembled from triplets of building blocks

  • Sushil K. Maurya,
  • Mark Dow,
  • Stuart Warriner and
  • Adam Nelson

Beilstein J. Org. Chem. 2013, 9, 775–785, doi:10.3762/bjoc.9.88

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  • of metathesis substrates by iterative attachment of simple unsaturated building blocks to a fluorous-tagged linker 1 (e.g., → 2 or 3). Subsequently, metathesis cascade reactions were used to “reprogram” the molecular scaffolds, concomitantly releasing the products from the linker (e.g., → 4 or 5) [14
  • isolated by solid-fluorous phase extraction (F-SPE), and its purity was determined by analysis by 500 MHz 1H NMR spectroscopy. Metathesis cascade reactions The scaffolds of the metathesis substrates were “reprogrammed” by treatment with Hoveyda–Grubbs second-generation catalyst in either dichloromethane or
  • cyclopentene did not participate in the metathesis reaction, and the bridged macrocycle 53 was obtained in low yield. We have previously observed the formation of macrocyclic metathesis products in similar metathesis cascade reactions [14]. The formation of the cyclopropanes 46 and 47 as byproducts in the
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Published 22 Apr 2013

A one-pot catalyst-free synthesis of functionalized pyrrolo[1,2-a]quinoxaline derivatives from benzene-1,2-diamine, acetylenedicarboxylates and ethyl bromopyruvate

  • Mohammad Piltan,
  • Loghman Moradi,
  • Golaleh Abasi and
  • Seyed Amir Zarei

Beilstein J. Org. Chem. 2013, 9, 510–515, doi:10.3762/bjoc.9.55

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  • reaction times and displayed limited reaction tolerance and low reaction selectivity [20][21]. Cheeseman and Tuck reported the first pyrrolo[1,2-a]quinoxaline in 1965 [22]. Recently, Patil et al. developed the PtBr2 and Au(I)-catalyzed hydroamination–hydroarylation cascade reactions of 2-(1H-pyrrol-1-yl
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Published 11 Mar 2013

Alternaric acid: formal synthesis and related studies

  • Michael C. Slade and
  • Jeffrey S. Johnson

Beilstein J. Org. Chem. 2013, 9, 166–172, doi:10.3762/bjoc.9.19

Graphical Abstract
  • transformations, cascade reactions, and multicomponent couplings have emerged as enabling tools for the synthesis of complex molecules [1][2]. Our laboratory [3][4][5][6][7][8][9][10][11][12][13][14][15][16] and others have developed [17] and employed [18][19] silyl glyoxylates 1 in a variety of synthetic
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Published 24 Jan 2013

Copper-catalyzed CuAAC/intramolecular C–H arylation sequence: Synthesis of annulated 1,2,3-triazoles

  • Rajkumar Jeyachandran,
  • Harish Kumar Potukuchi and
  • Lutz Ackermann

Beilstein J. Org. Chem. 2012, 8, 1771–1777, doi:10.3762/bjoc.8.202

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  • -economical syntheses of annulated 1,2,3-triazoles were accomplished through copper-catalyzed intramolecular direct arylations in sustainable one-pot reactions. Thus, catalyzed cascade reactions involving [3 + 2]-azide–alkyne cycloadditions (CuAAC) and C–H bond functionalizations provided direct access to
  • arylation; in particular, because of the notable biological activities exerted by fully substituted 1,2,3-triazoles [74][75][76][77][78][79][80][81][82][83][84][85][86][87][88]. As a consequence, we wish to present herein novel cascade reactions, in which cost-effective copper(I) compounds serve as the
  • (Scheme 5). Conclusion In summary, we have reported on the use of inexpensive copper(I) complexes for step- and atom-economical sequential catalytic transformations involving direct C–H bond arylations. Thus, CuI enabled the synthesis of fully substituted 1,2,3-triazoles through cascade reactions
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Published 16 Oct 2012

Organocatalytic cascade aza-Michael/hemiacetal reaction between disubstituted hydrazines and α,β-unsaturated aldehydes: Highly diastereo- and enantioselective synthesis of pyrazolidine derivatives

  • Zhi-Cong Geng,
  • Jian Chen,
  • Ning Li,
  • Xiao-Fei Huang,
  • Yong Zhang,
  • Ya-Wen Zhang and
  • Xing-Wang Wang

Beilstein J. Org. Chem. 2012, 8, 1710–1720, doi:10.3762/bjoc.8.195

Graphical Abstract
  • , organocatalytic domino/cascade reactions have come into focus and become a powerful synthetic approach that allows the construction of structurally diverse and complex molecules, minimizes the number of manual operations, and saves time, effort, and production costs [45][46][47]. Thus, many nitrogen-containing
  • , entry 14). However, with increasing catalyst loading from catalytic to stoichiometric amounts, the corresponding cascade reactions could provide the major products in 72 and 66% yields (Table 2, entries 15 and 16). In all the reactions, high diastereoselectivity could be obtained (>20:1 dr). Finally, we
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Published 09 Oct 2012

Organocatalytic tandem Michael addition reactions: A powerful access to the enantioselective synthesis of functionalized chromenes, thiochromenes and 1,2-dihydroquinolines

  • Chittaranjan Bhanja,
  • Satyaban Jena,
  • Sabita Nayak and
  • Seetaram Mohapatra

Beilstein J. Org. Chem. 2012, 8, 1668–1694, doi:10.3762/bjoc.8.191

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  • by Xu and co-workers. Chiral secondary amine promoted oxa-Michael–aldol cascade reactions as reported by Wang and co-workers. Reaction of salicyl-N-tosylimine with aldehydes by domino oxa-Michael/aza-Baylis–Hillman reaction, as reported by Alemán and co-workers. Silyl prolinol ether-catalyzed oxa
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Published 04 Oct 2012
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