Asymmetric organocatalyzed synthesis of coumarin derivatives

• Natália M. Moreira,
• Lorena S. R. Martelli and
• Arlene G. Corrêa

Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128

• , the advances in asymmetric organocatalyzed synthesis of coumarin derivatives are discussed in this review, according to the mode of activation of the catalyst. Keywords: asymmetric synthesis; green chemistry; 2H-chromen-2-one; organocatalysis; Introduction Coumarins are important naturally occurring

• ammonium salts derived from cinchona alkaloids [28]. Therefore, the asymmetric synthesis of coumarin derivatives is herein presented according to the activation mode, i.e., via covalent or non-covalent bonding. Furthermore, the use of bifunctional catalysts and multicatalysis are discussed as well

• product 17 was obtained in 15 steps with 6% overall yield. Although chiral secondary amines have proved to be particularly useful catalysts, primary amines as organocatalysts in asymmetric synthesis have also played a significant role [36]. For instance, Kim et al. described the enantioselective Michael

2,4-Bis(arylethynyl)-9-chloro-5,6,7,8-tetrahydroacridines: synthesis and photophysical properties

• Najeh Tka,
• Mohamed Adnene Hadj Ayed,
• Mourad Ben Braiek,
• Mahjoub Jabli,
• Noureddine Chaaben,
• Kamel Alimi,
• Stefan Jopp and
• Peter Langer

Beilstein J. Org. Chem. 2021, 17, 1629–1640, doi:10.3762/bjoc.17.115

• Najeh Tka Mohamed Adnene Hadj Ayed Mourad Ben Braiek Mahjoub Jabli Noureddine Chaaben Kamel Alimi Stefan Jopp Peter Langer Asymmetric Synthesis and Molecular Engineering Laboratory for Organic Electronic Materials, Faculty of sciences of Monastir, Monastir university, Environment street, 5019

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• heterocycles. The present work will comprehensively cover the most pertinent contributions to this research area from 2012 to 2020. We regret in advance that some contributions are excluded in order to maintain a concise format. Keywords: asymmetric synthesis; chiral auxiliary; natural products; nitrogen

• important tool in the asymmetric synthesis of aziridines [25][26], α-amino acids [27][28], β-amino acids [23][29] and branched α-amines [30][31]. The Darzens-type asymmetric synthesis of N-(p-toluenesulfinyl)aziridine 2-carboxylate esters (7 and 8) was described through the addition of lithium α

• -butanesulfonamide and applications in some nucleophilic additions, the next sections will describe the synthesis of several alkaloids according to the size of the heterocycles. We regret in advance that some contributions are excluded in order to maintain a concise format. Review Asymmetric synthesis of aziridines

Prins cyclization-mediated stereoselective synthesis of tetrahydropyrans and dihydropyrans: an inspection of twenty years

• Asha Budakoti,
• Pradip Kumar Mondal,
• Prachi Verma and
• Jagadish Khamrai

Beilstein J. Org. Chem. 2021, 17, 932–963, doi:10.3762/bjoc.17.77

• , followed by removal of trimethylsilane (Scheme 50). The authors further explored this strategy for the asymmetric synthesis of 3-vinylidene-substituted tetrahydropyran by taking the chiral propargylsilane. A diastereoselective route to cis-2,6-disubstituted tetrahydropyran-4-one 215 was explored by

Chiral isothiourea-catalyzed kinetic resolution of 4-hydroxy[2.2]paracyclophane

• David Weinzierl and
• Mario Waser

Beilstein J. Org. Chem. 2021, 17, 800–804, doi:10.3762/bjoc.17.68

• polymer chemistry [1][2][7][8][9], these planar chiral molecules have been very successfully used in asymmetric catalysis [3][4][10][11][12]. Accordingly, the development of methods for the asymmetric synthesis of enantiomerically pure, or at least enantiomerically enriched, derivatives that can be

• decades, it was shown that enantioenriched 2 may serve as a valuable building block to access more advanced chiral cyclophane ligands and catalysts [3][4][19][20][21][22] and therefore its asymmetric synthesis became an important task [3][4][18][19][20][21][22][23][24][25][26][27]. Several strategies to

The synthesis of chiral β-naphthyl-β-sulfanyl ketones via enantioselective sulfa-Michael reaction in the presence of a bifunctional cinchona/sulfonamide organocatalyst

• Deniz Tözendemir and
• Cihangir Tanyeli

Beilstein J. Org. Chem. 2021, 17, 494–503, doi:10.3762/bjoc.17.43

• %) catalyst loading. Selected enantiomerically enriched sulfa-Michael addition products were subjected to oxidation to obtain the corresponding sulfones. Keywords: asymmetric synthesis; bifunctional catalysis; cinchona alkaloids; organocatalysis; sulfa-Michael reaction; Introduction Derivatives of the

Synthetic strategies of phosphonodepsipeptides

• Jiaxi Xu

Beilstein J. Org. Chem. 2021, 17, 461–484, doi:10.3762/bjoc.17.41

• the P–C bond of the spirophosphoranes 201 readily proceeded at room temperature in the presence of moist solvents to give the corresponding phosphonodepsipeptides 202 in high yields (Scheme 37) [56]. An asymmetric synthesis of this class of phosphonodepsipeptides was realized with enantiopure (S)-α

• -hydroxyisovaleric acid-derived spirophosphoranes as the phosphorus reagents [57]. By using a similar strategy, linker-linked bisphosphonodepsidipeptides were synthesized [10]. The current method is also an interesting synthetic strategy of phosphonodepsipeptides. It can realize an asymmetric synthesis of

Direct synthesis of anomeric tetrazolyl iminosugars from sugar-derived lactams

• Michał M. Więcław and
• Bartłomiej Furman

Beilstein J. Org. Chem. 2021, 17, 115–123, doi:10.3762/bjoc.17.12

• Michal M. Wieclaw Bartlomiej Furman Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland 10.3762/bjoc.17.12 Abstract Herein we present the direct asymmetric synthesis of tetrazole-functionalized 1-deoxynojirimycin derivatives from simple sugars via a

Recent progress in the synthesis of homotropane alkaloids adaline, euphococcinine and N-methyleuphococcinine

• Dimas J. P. Lima,
• Antonio E. G. Santana,
• Michael A. Birkett and
• Ricardo S. Porto

Beilstein J. Org. Chem. 2021, 17, 28–41, doi:10.3762/bjoc.17.4

• subjected to simultaneous catalytic hydrogenation and hydrogenolysis of the protecting group Cbz to give (−)-adaline (1) in 90% yield. The asymmetric synthesis achieved by Liebeskind et al. presented a high enantiomeric excess and good yields. Also, the proposed route differed from the previously mentioned

Convenient access to pyrrolidin-3-ylphosphonic acids and tetrahydro-2H-pyran-3-ylphosphonates with multiple contiguous stereocenters from nonracemic adducts of a Ni(II)-catalyzed Michael reaction

• Alexander N. Reznikov,
• Dmitry S. Nikerov,
• Anastasiya E. Sibiryakova,
• Victor B. Rybakov,
• Evgeniy V. Golovin and
• Yuri N. Klimochkin

Beilstein J. Org. Chem. 2020, 16, 2073–2079, doi:10.3762/bjoc.16.174

• analogues 4 and 5 are neuraminidase inhibitors (Figure 1) [8][9]. These circumstances create an interest in discovering synthetic routes for obtaining nonracemic phosphoryl-substituted heterocycles. Thus, in recent years, effective methods for the asymmetric synthesis of chiral phosphonates containing

The biomimetic synthesis of balsaminone A and ellagic acid via oxidative dimerization

• Sharna-kay Daley and
• Nadale Downer-Riley

Beilstein J. Org. Chem. 2020, 16, 2026–2031, doi:10.3762/bjoc.16.169

• ; ellagic acid; oxidative dimerization; Introduction Over the last century, the formation of an aryl to aryl bond has garnered considerable synthetic attention due to the applications of biaryls as pharmaceutical agents, as well as chiral auxiliaries in asymmetric synthesis [1][2][3]. Methods such as the

Syntheses of spliceostatins and thailanstatins: a review

• William A. Donaldson

Beilstein J. Org. Chem. 2020, 16, 1991–2006, doi:10.3762/bjoc.16.166

• asymmetric synthesis of a (Z)-2-hydroxy-3-pentene unit, with most proceeding via the cis-reduction of 4-acetoxy-2-pentynoic acid (13). The synthesis by Kitahara et al. [8][9] is the exception, where the chiral center is derived from relatively inexpensive (S)-ethyl lactate (14). This was transformed into the

Stereoselective Biginelli-like reaction catalyzed by a chiral phosphoric acid bearing two hydroxy groups

• Xiaoyun Hu,
• Jianxin Guo,
• Cui Wang,
• Rui Zhang and
• Victor Borovkov

Beilstein J. Org. Chem. 2020, 16, 1875–1880, doi:10.3762/bjoc.16.155

• activities [7][8]. For example, (S)-monastrol is 15-fold more effective in the inhibition of Eg 5 ATPase than its enantiomer, (R)-monastrol [9]. As more reports on the enantiospecific biological activity of DMPMs came to light, the development of an efficient and reliable asymmetric synthesis of enantiopure

On the hydrolysis of diethyl 2-(perfluorophenyl)malonate

• Ilya V. Taydakov and
• Mikhail A. Kiskin

Beilstein J. Org. Chem. 2020, 16, 1863–1868, doi:10.3762/bjoc.16.153

• ., pharmacologically active substances [1][2][3][4][5], in asymmetric synthesis and catalysis [6][7][8], as precursors of heterocyclic compounds [9][10][11], as ligands in coordination chemistry [12][13][14][15][16] and for other applications [17][18]. Incorporation of fluorine atoms into an organic molecule is known

Pauson–Khand reaction of fluorinated compounds

• Jorge Escorihuela,
• Daniel M. Sedgwick,
• Alberto Llobat,
• Mercedes Medio-Simón,
• Pablo Barrio and
• Santos Fustero

Beilstein J. Org. Chem. 2020, 16, 1662–1682, doi:10.3762/bjoc.16.138

• fluorine-containing N-tethered 1,7-enynes [61]. Intramolecular PKR of chiral N-tethered fluorinated 1,7-enynes [61]. Examples of further modifications to the Pauson−Khand adducts [61]. Asymmetric synthesis the fluorinated enynes 53. Intramolecular PKR of chiral N-tethered 1,7-enynes 53 [64]. Intramolecular

Recent synthesis of thietanes

• Jiaxi Xu

Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116

• performed the absolute asymmetric synthesis of highly rigid thietane-fused β-lactams 356 from achiral monothioimides 355 using a chiral crystal environment through a topochemically controlled intramolecular photochemical [2 + 2] cycloaddition in a benzene solution. Only the 2-methylacrylamide derivative

The charge-assisted hydrogen-bonded organic framework (CAHOF) self-assembled from the conjugated acid of tetrakis(4-aminophenyl)methane and 2,6-naphthalenedisulfonate as a new class of recyclable Brønsted acid catalysts

• Svetlana A. Kuznetsova,
• Alexander S. Gak,
• Yulia V. Nelyubina,
• Vladimir A. Larionov,
• Han Li,
• Michael North,
• Vladimir P. Zhereb,
• Alexander F. Smol'yakov,
• Artem O. Dmitrienko,
• Michael G. Medvedev,
• Igor S. Gerasimov,
• Ashot S. Saghyan and
• Yuri N. Belokon

Beilstein J. Org. Chem. 2020, 16, 1124–1134, doi:10.3762/bjoc.16.99

• ][31], gas separation and absorption [28][29], enzyme encapsulation [36], and even asymmetric synthesis (albeit with a framework that contained a transition metal ion) [37]. However, for the HOF and CAHOF catalysts to have a similar appeal to other regular active site distribution materials, such as

Asymmetric synthesis of CF₂-functionalized aziridines by combined strong Brønsted acid catalysis

• Xing-Fa Tan,
• Fa-Guang Zhang and
• Jun-An Ma

Beilstein J. Org. Chem. 2020, 16, 638–644, doi:10.3762/bjoc.16.60

Architecture and synthesis of P,N-heterocyclic phosphine ligands

• Wisdom A. Munzeiwa,
• Bernard Omondi and
• Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

• precursors. However, asymmetric synthesis can be used as strategy to introduce stereogenic P-atoms into the ligand’s backbone. The borane complexation approach is a unique stereoselective way for introducing a P-stereogenic center. Benoit et al. [2] reported on the synthesis of 2-phenyl-1,3,2

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

• Munmun Ghosh,
• Valmik S. Shinde and
• Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

• by Wattanakit described several approaches for the development of chiral metal electrodes for enantioselective recognition and asymmetric synthesis developed over the past decade [18]. Concurrent with pioneering works in the field of asymmetric induction in electrochemical reduction on chiral mercury

• electrochemical asymmetric oxidation of 1,2-diols 74 and amino alcohols 77 in presence of a Br- mediator using Cu(OTf)2 and (R,R)-Ph-BOX 76 as the catalytic system (Scheme 29). The method enabled an asymmetric synthesis of α-hydroxycycloalkanones 75 and α-amino esters 78 along with the kinetic resolution of

• using a bimetallic Pt@Cu cathode. Enantioselective reduction of ketones at mercury cathode using N,N'-dimethylquininium tetrafluoroborate as chiral inductor. Asymmetric synthesis of an amino acid using an electrode modified with amino acid oxidase and electron mediator. Asymmetric oxidation of p-tolyl

Synthetic terpenoids in the world of fragrances: Iso E Super^® is the showcase

• Alexey Stepanyuk and
• Andreas Kirschning

Beilstein J. Org. Chem. 2019, 15, 2590–2602, doi:10.3762/bjoc.15.252

• : asymmetric synthesis; fragrances; odorants; sandalwood; scents; terpenes; terpenoids; Review “Iso E Super® is to perfume what Tango Nuevo is to Tango Argentino” [1] Introduction – classical terpenes in perfumes Perfumes (Latin “per fumus”, which means “through smoke”) have accompanied mankind for thousands

• of the oxime derivative of (−)-(1R,2S)-Georgywood® ((−)-35) [33][34]. Corey´s asymmetric synthesis of Iso E Super Plus® ((+)-34) is initiated by a stereoselective Diels–Alder cycloaddition utilizing the CBS catalyst (36) to yield the cyclohexene derivative 42 with good facial selectivity [33

Synthesis of acremines A, B and F and studies on the bisacremines

• Nils Winter and
• Dirk Trauner

Beilstein J. Org. Chem. 2019, 15, 2271–2276, doi:10.3762/bjoc.15.219

• two acremine units through a dioxysilane (Scheme 6) [24][25][26]. Unfortunately, irradiation of 25 with and without the presence of different photosensitizers only led to decomposition. Conclusion In conclusion, we report the first asymmetric synthesis of acremine F (5) relying on the combination of a

α-Photooxygenation of chiral aldehydes with singlet oxygen

• Dominika J. Walaszek,
• Magdalena Jawiczuk,
• Jakub Durka,
• Olga Drapała and
• Dorota Gryko

Beilstein J. Org. Chem. 2019, 15, 2076–2084, doi:10.3762/bjoc.15.205

• ,3S) to the anti’-6 isomer. Based on the known relationship between syn-6 and anti’-6 diols and the other two diastereoisomers we assigned their absolute configuration as (2S,3S) for syn’-6 and (2S,3R) for anti-6, respectively. Asymmetric synthesis of 3,4-diphenylbutane-1,2-diol To confirm our

• ). Stereoselective α-photooxygenation of 3,4-diphenylbutanal (1) with 1O2. Schematic representation of the in situ methodology and preferred conformation of diols with Mo2 core. Asymmetric synthesis of 3,4-diphenylbutane-1,2-diol. Stereoselectivity of α-photooxygenation reaction of 3,4-diphenylbutanal (1

A review of the total syntheses of triptolide

• Xiang Zhang,
• Zaozao Xiao and
• Hongtao Xu

Beilstein J. Org. Chem. 2019, 15, 1984–1995, doi:10.3762/bjoc.15.194

• syntheses of triptolide. In 2014, Li and co-workers further reported a formal asymmetric synthesis of triptolide from tetralone 24 (Figure 2, route B and Scheme 2) [50], featuring a Robinson annulation of Nazarov’s reagent 25 with 5-methoxy-2-tetralone 24 in the presence of enantiomerically pure (R)-α

• -workers reported an asymmetric synthesis of triptolide using readily available ʟ-dehydroabietic acid (26) as starting material (Figure 2, route C and Scheme 3) [67]. In this synthesis, the key step was the construction of the butenolide (D-ring). ʟ-Dehydroabietic acid was converted to C-14

• ), minnelide (6) and LLDT-8 (7). Syntheses of triptolide. Berchtold’s synthesis of triptolide. Li’s formal synthesis of triptolide. van Tamelen’s asymmetric synthesis of triptonide and triptolide. Van Tamelen’s (method II) formal synthesis of triptolide. Sherburn’s formal synthesis of triptolide. van Tamelen’s

N-(1-Phenylethyl)aziridine-2-carboxylate esters in the synthesis of biologically relevant compounds

• Iwona E. Głowacka,
• Aleksandra Trocha,
• Andrzej E. Wróblewski and
• Dorota G. Piotrowska

Beilstein J. Org. Chem. 2019, 15, 1722–1757, doi:10.3762/bjoc.15.168

• efficiency of a 2-substituted N-(1-phenylethyl)aziridine framework as chiron bearing a chiral auxiliary. Keywords: alkaloids; amino acids; asymmetric synthesis; ceramides; chiral catalysis; chiral pool; N-(1-phenylethyl)aziridine chiron; sphingoids; Introduction The synthesis of enantiomerically pure

• compounds belongs to the most challenging tasks in organic chemistry for several reasons, just to mention structural studies of natural products or preparation of chiral drugs. They become available by asymmetric synthesis frequently employing chiral synthons (chirons) [1]. Chirons contain functional groups

• of chemical and configurational stability was achieved by introducing N,N-dibenzylserinals 4 [10]. Another important strategy of asymmetric synthesis relies on chiral auxiliaries, i.e., a specially selected homochiral part of a starting material governing the stereoselectivity of subsequent reactions