β-Hydroxy sulfides and their syntheses

• Mokgethwa B. Marakalala,
• Edwin M. Mmutlane and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1668–1692, doi:10.3762/bjoc.14.143

• atmosphere [50]. Product yields ranged from 18 to 96%, but in moderate enantioselectivities of 20–64% ee (Scheme 16). Sun and co-workers reported the use of BINOL-based Brønsted acid catalysts such as TRIP 60 for the asymmetric thiolysis of meso-epoxides with benzothiazoles 62 as nucleophiles as shown in

• ranged from –78 °C to room temperature. The use of amines, alcohols as well as alkyl and arylthiols as nucleophiles failed to provide the corresponding products. A year later, Antilla and co-workers found lithium-binol phosphate 64 to be an efficient catalyst for the desymmetrization of meso-epoxides

• complex. Enantioselective ring-opening reaction of stilbene oxides with ArSH catalyzed by a C2-symmetric chiral bipyridyldiol–titanium complex. Asymmetric desymmetrization of meso-epoxides using BINOL-based Brønsted acid catalysts. Lithium-BINOL-phosphate-catalyzed desymmetrization of meso-epoxides with

Recent applications of chiral calixarenes in asymmetric catalysis

• Mustafa Durmaz,
• Erkan Halay and
• Selahattin Bozkurt

Beilstein J. Org. Chem. 2018, 14, 1389–1412, doi:10.3762/bjoc.14.117

• selectivity was the chiral oxazoline unit and not the inherent chirality of calixarene skeleton. Asymmetric hydrogenation Starting with distally O-dialkylated calixarene precursors, a series of BINOL-derived calix[4]arene-diphosphite ligands 40a–g were synthesized by Liu and Sandoval through phosphorylation

• applied in the palladium-catalyzed Tsuji–Trost allylation reaction. BINOL-derived calix[4]arene-diphosphite ligands. Inherently chiral calix[4]arene 43 containing a diarylmethanol structure. Calix[4]arene-based chiral primary amine–thiourea catalysts. Novel prolinamide organocatalysts based on the calix[4

Synthesis of chiral 3-substituted 3-amino-2-oxindoles through enantioselective catalytic nucleophilic additions to isatin imines

• Hélène Pellissier

Beilstein J. Org. Chem. 2018, 14, 1349–1369, doi:10.3762/bjoc.14.114

• diastereomers (>90% de) in both uniformly excellent yields (90–98%) and enantioselectivities (94–99% ee). In only one case of substrate (Ar = 1-Naph), a lower yield (78%) albeit combined with a comparable very good enantioselectivity (93% ee) was obtained. The same year, (S)-BINOL-derived tin dibromide 30 was

• trimethylsilyl ether. However, also metal complexes (Zn, Sn) derived from N,N’-dioxide and BINOL-derived ligands have been employed affording the products with enantioselectivities of up to 90–99% ee. Moreover, comparable enantioselectivities of up to 99% ee were reported in aza-Morita–Baylis–Hilman reactions

Copper-catalyzed asymmetric methylation of fluoroalkylated pyruvates with dimethylzinc

• Kohsuke Aikawa,
• Kohei Yabuuchi,
• Kota Torii and
• Koichi Mikami

Beilstein J. Org. Chem. 2018, 14, 576–582, doi:10.3762/bjoc.14.44

• have so far been reported [7][28][29][30]. In 2007, Gosselin and Britton et al. reported that treatment of ethyl trifluoropyruvate (1a) with (R)-BINOL-mediated organozincate as a chiral methylating regent provided the corresponding methylated tertiary alcohol 2a in moderate enantioselectivity (Scheme 1

Investigations towards the stereoselective organocatalyzed Michael addition of dimethyl malonate to a racemic nitroalkene: possible route to the 4-methylpregabalin core structure

• Denisa Vargová,
• Rastislav Baran and
• Radovan Šebesta

Beilstein J. Org. Chem. 2018, 14, 553–559, doi:10.3762/bjoc.14.42

• an additional hydrogen bond donor group was not tested in too much depth. Therefore, we have synthesized two binaphthol-based diastereomeric squaramide catalysts (Sa,R,R)-C8 and (Sa,S,S)-C8 (Scheme 3). Starting from (S)-BINOL (8), amine 9 was obtained in five steps following literature procedures

Recent developments in the asymmetric Reformatsky-type reaction

• Hélène Pellissier

Beilstein J. Org. Chem. 2018, 14, 325–344, doi:10.3762/bjoc.14.21

• aldehydes as electrophiles [38]. Enantioselectivities of up to 84% ee were achieved by using a BINOL derivative as chiral ligand. Ever since, other types of chiral ligands including chiral Schiff bases [39], bisoxazolidines [40], 1,2-amino alcohols [41], indolinylmethanols [42], and diarylprolinols have

• alcohols and BINOL (1,1’-bi-2-naphthol) derivatives, ligand 53 was selected as optimal ligand when used at a stoichiometric amount in THF at −40 °C. As shown in Scheme 21, the corresponding fluorinated chiral β-amino alcohol 54 was formed in both moderate yield (60%) and enantioselectivity (37% ee

A new member of the fusaricidin family – structure elucidation and synthesis of fusaricidin E

• Marcel Reimann,
• Louis P. Sandjo,
• Luis Antelo,
• Eckhard Thines,
• Isabella Siepe and
• Till Opatz

Beilstein J. Org. Chem. 2017, 13, 1430–1438, doi:10.3762/bjoc.13.140

• allylation with BINOL-titanium catalysts failed due to low conversion [14]; however, in spite of good experience with the Maruoka–Keck allylation in another total synthesis, the conversion was not satisfying in this case [15]. After protection and guanidinylation with triflylguanidine 14, the homoallylic

Conjugate addition–enantioselective protonation reactions

• James P. Phelan and
• Jonathan A. Ellman

Beilstein J. Org. Chem. 2016, 12, 1203–1228, doi:10.3762/bjoc.12.116

• catalytic (R)-3,3’-dibromo-BINOL (16) and stoichiometric SnCl4 [19] (Scheme 4). The authors proposed that complex 18 acted as a chiral proton source to protonate a tin-enolate intermediate based upon related complexes that the Yamamoto group had previously used for the enantioselective protonation of silyl

• lower enantioselectivities for the addition of para-substituted anilines to α,β-unsaturated imines [41]. Gil and Collin have also reported on the same reaction as Sodeoka, but using a samarium-BINOL catalyst system, which proceeded with lower enantioselectivity [42]. Sodeoka found that minimizing the

• co-workers demonstrated that chiral lanthanum and samarium tris(BINOL) complexes (Figure 3), developed by the Shibasaki group for asymmetric Michael additions using malonates and organometallic reagents, are effective catalysts for the sequential conjugate addition of 4-tert-butyl(thiophenol) to α,β

Catalytic asymmetric synthesis of biologically important 3-hydroxyoxindoles: an update

• Bin Yu,
• Hui Xing,
• De-Quan Yu and
• Hong-Min Liu

Beilstein J. Org. Chem. 2016, 12, 1000–1039, doi:10.3762/bjoc.12.98

• ’-position of the BINOL backbone had a remarkable effect on the catalytic activity and enantioselectivity. Based on this method, the authors also achieved the synthesis of a key intermediate efficiently (99% yield and 93% ee), which had been used in the total synthesis of (+)-folicanthine [68]. The Zhang

• enantioselectivity were observed when the reactions were performed only in the presence of 10 mol % cinchona alkaloid amine catalyst and TFA (30 mol %). It was found that (S)-BINOL-derived CPA catalyst can significantly improve the stereochemical control of the cinchona alkaloid amine catalyst, while (R)-CPA

A modular approach to neutral P,N-ligands: synthesis and coordination chemistry

• Vladislav Vasilenko,
• Torsten Roth,
• Clemens K. Blasius,
• Sebastian N. Intorp,
• Hubert Wadepohl and
• Lutz H. Gade

Beilstein J. Org. Chem. 2016, 12, 846–853, doi:10.3762/bjoc.12.83

• aromatic formamidines (1a–c) starting from triethyl orthoformate and aromatic amines. Low-temperature lithiation of 1 and addition to achiral (R = Ph) and axially chiral (R2 = BINOL) chlorophosphines R2PCl gave ligands 2 and 3 in excellent yields (Scheme 1) [11]. If the correct stoichiometry is maintained

• -fluorophenyl; R = phenyl or BINOL. Yields: [2a-Rh(cod)]BF4 = 85%, [2b-Rh(cod)]BF4 = 75%, [2c-Rh(cod)]BF4 = 88%, [3a-Rh(cod)]BF4 = 74%, [3b-Rh(cod)]BF4 = 90%, [3c-Rh(cod)]BF4 = 81%, [2a-Ir(cod)]BF4 = 77%, [2b-Ir(cod)]BF4 = 80%, [2c-Ir(cod)]BF4 = 88%, [3a-Ir(cod)]BF4 = 65%, [3b-Ir(cod)]BF4 = 81%, [3c-Ir(cod)]BF4

Cupreines and cupreidines: an established class of bifunctional cinchona organocatalysts

• Laura A. Bryant,
• Rossana Fanelli and
• Alexander J. A. Cobb

Beilstein J. Org. Chem. 2016, 12, 429–443, doi:10.3762/bjoc.12.46

• developed an aza-MBH process using β-ICPD in the reaction between N-sulfonyl-1-aza-1,3-butadienes and activated alkenes (Scheme 4) [25]. In this report, optimal selectivity required (R)-BINOL as a co-catalyst (see inset for proposed catalytic transition state – (R)-BINOL shown in red). Furthermore, the

• the flexible cinchona framework, which has a knock-on effect on the catalytic outcome. Interestingly, the chiral nature of the binol phosphoric acid catalyst (S)-49 in the anti-selective process was not thought to be hugely influential upon the stereochemical outcome. Indeed replacing it with diphenyl

• processes catalyzed by β-ICPD, as demonstrated by Shi and Li and co-workers. (b) Takizawa and co-workers demonstrated similar chemistry, but also utilized the catalyst α-ICPN (inset). (a) Chen’s asymmetric MBH reaction. Good selectivity was dependent upon the presence of (R)-BINOL (shown in red) as well as

Self and directed assembly: people and molecules

• Tony D. James

Beilstein J. Org. Chem. 2016, 12, 391–405, doi:10.3762/bjoc.12.42

• important it is to read and keep up to date with the literature. Taking that one step further, it is also very important to keep abreast of papers that cite your own work. This is clearly illustrated using a paper by Todd A. Houston, who discovered that the racemic form of our chiral binol boronic acid 8

• formed very strongly complexes with tartaric acid [60]. This paper made us realise that our chiral binol boronic acid 8 should be able to discriminate the enantiomers of tartaric acid and also bind strongly with other sugar acids. Therefore, with Jianzhang Zhao an outstanding Postdoctoral Research Fellow

• enantiomers of tartaric acid and also bound bind strongly with other sugar acids [61] (Figure 9). While, we were very happy with these results, we realised that the system could be improved by changing the fluorophore from binol, to a much better fluorophore such as anthracene. Therefore, we combined the

Recent advances in copper-catalyzed asymmetric coupling reactions

• Fengtao Zhou and
• Qian Cai

Beilstein J. Org. Chem. 2015, 11, 2600–2615, doi:10.3762/bjoc.11.280

• advantage of a chiral (R)-BINOL-bridge to link the two aromatic acids and obtained the coupling product with excellent stereocontrol (up to 100% de) (Scheme 1) [16][17][18][19]. In 1998, Martin et al. [20] applied this strategy to the asymmetric intramolecular biaryl coupling of sugar derivatives carrying 2

• )butanoates with CuI/BINOL-derived ligands in 2013, affording the chiral coupling products and recovered starting material with high enantioselectivity (Scheme 21). Recently, the aforementioned kinetic resolution strategy was applied to another type of substrates [51], leading to the formation of cyano

Synthesis of bi- and bis-1,2,3-triazoles by copper-catalyzed Huisgen cycloaddition: A family of valuable products by click chemistry

• Zhan-Jiang Zheng,
• Ding Wang,
• Zheng Xu and
• Li-Wen Xu

Beilstein J. Org. Chem. 2015, 11, 2557–2576, doi:10.3762/bjoc.11.276

• 5,5’-bitriazoles from acetylenic amide. The amine-functionalized polysiloxane-mediated divergent synthesis of trizaoles and bitriazoles. The cyclic BINOL-based 5,5’-bitriazoles. The one-pot click–click reactions for the synthesis of bistriazoles. The synthesis of bis(indolyl)methane-derivatized 1,2,3

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

• 308 in the presence of CuSO4 and sodium ascorbate in acetonitrile/water to deliver the desired cyclophane derivative 309 (56%, Scheme 53). Similarly, a novel BINOL-based cyclophane 310 has been synthesized via click chemistry by incorporating two triazole moieties in the macrocycle [187]. Li and co

Diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams

• Katherine M. Byrd

Beilstein J. Org. Chem. 2015, 11, 530–562, doi:10.3762/bjoc.11.60

• many ligands, magnesium–BINOL complex was identified as suitable catalyst for the 1,4-cyanation of 107. The authors obtained the 1,4-cyano products in both moderate to high yields and enantioselectivities for a variety of β-aryl substituted N-acylpyrazoles (Scheme 26). In 2007, Shibasaki and co-workers

• reported the asymmetric 1,4-addition of dibenzyl malonate to α,β-unsaturated N-acylpyrroles catalyzed by a La(OiPr)3–linked BINOL complex [220]. Optimal yields and enantioselectivies were realized by adding 1,1,1,3,3,3-hexafluoroisopropanol (HIFP) to the reaction mixture and by placing steric bulk near the

Chemistry of polyhalogenated nitrobutadienes, 14: Efficient synthesis of functionalized (Z)-2-allylidenethiazolidin-4-ones

• Viktor A. Zapol’skii,
• Jan C. Namyslo,
• Mimoza Gjikaj and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2014, 10, 1638–1644, doi:10.3762/bjoc.10.170

• Supporting Information File 1). For comparison, the well-known atropisomer 1,1’-binaphthalene-2,2’-diol (BINOL) shows a rotational barrier of 158 kJ/mol with calculated data in good accordance with the experimental value [46]. In addition to substantial NMR, IR, and mass spectral characterization of the

Homochiral BINOL-based macrocycles with π-electron-rich, electron-withdrawing or extended spacing units as receptors for C₆₀

• Marco Caricato,
• Silvia Díez González,
• Idoia Arandia Ariño and
• Dario Pasini

Beilstein J. Org. Chem. 2014, 10, 1308–1316, doi:10.3762/bjoc.10.132

• several homochiral macrocycles has been achieved by using π-electron-rich, electron-deficient or extended aromatic dicarboxylic acids in combination with an axially-chiral dibenzylic alcohol, derived from enantiomerically-pure BINOL. Two series of cyclic adducts with average molecular D2 and D3 molecular

• cyclic adducts exhibit recognition properties towards C60 in toluene solutions (up to log Ka = 3.2) with variable stoichiometries and variable intensities of the charge-tranfer band upon complexation. Keywords: BINOL; C60; carbon nanomaterials; carbon nanostructures; chirality; macrocycles; sensors

• protocol for the preparation of several chiral macrocycles incorporating BINOL (1,1′-bi-2-naphthol) units, through the formation of bridging ester functionalities, which ensure chemical inertness for the purposes of supramolecular sensing, recognition, or self-assembly. We have shown their application in

Self-assembly of metallosupramolecular rhombi from chiral concave 9,9’-spirobifluorene-derived bis(pyridine) ligands

• Rainer Hovorka,
• Sophie Hytteballe,
• Torsten Piehler,
• Georg Meyer-Eppler,
• Filip Topić,
• Kari Rissanen,
• Marianne Engeser and
• Arne Lützen

Beilstein J. Org. Chem. 2014, 10, 432–441, doi:10.3762/bjoc.10.40

• far we have studied templates based on the Tröger’s base [27] and the 2,2’-dihydroxybinaphthyl (BINOL) [28] scaffold and identified the bend angle of these V-shaped compounds to be a critical factor for the degree of self-sorting that can be achieved [9][15][16][17][18][25][26][27][28]. The 9,9

New hydrogen-bonding organocatalysts: Chiral cyclophosphazanes and phosphorus amides as catalysts for asymmetric Michael additions

• Helge Klare,
• Jörg M. Neudörfl and
• Bernd Goldfuss

Beilstein J. Org. Chem. 2014, 10, 224–236, doi:10.3762/bjoc.10.18

• Helge Klare Jorg M. Neudorfl Bernd Goldfuss Department of Chemistry, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany, Fax: +49(0)221-470-5057 10.3762/bjoc.10.18 Abstract Ten novel hydrogen-bonding catalysts based on open-chain PV-amides of BINOL and chinchona alkaloids as well as three

• ; Chakravarty et al. [24] tested an ansa-bridged BINOL-based PV-cyclodiphosphazane in the asymmetric reduction of acetophenone with BH3 (5–8% ee), while Gade et al. [25] recently introduced BINOL-based PIII-cyclodiphosphazane ligands to transition-metal catalysis (up to 84% ee). We anticipated that by

• in activating a hydrogen-bond-acceptor than commonly employed (thio)ureas. Synthesis of chiral open-chain PV-amides We evaluated both BINOL and chinchona alkaloids as chiral backbones. BINOL is a well-established chiral motif [30], while chinchona alkaloids are sterically very demanding, can be

A combined continuous microflow photochemistry and asymmetric organocatalysis approach for the enantioselective synthesis of tetrahydroquinolines

• Erli Sugiono and
• Magnus Rueping

Beilstein J. Org. Chem. 2013, 9, 2457–2462, doi:10.3762/bjoc.9.284

• the synthesis of tetrahydroquinolines from readily available 2-aminochalcones using a combination of photochemistry and asymmetric Brønsted acid catalysis. The photocylization and subsequent reduction was performed with catalytic amount of chiral BINOL derived phosphoric acid diester and Hantzsch

• optically active tetrahydroquinolines. Readily available substituted 2-aminochalcones were envisioned to undergo photocyclization to the corresponding quinolines which in the presence of a chiral BINOL-derived phosphoric acid diester and Hantzsch dihydropyridine as hydride donor [32][33][34][35][36][37

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• protocol for resolving the racemate on large scale using (S)-BINOL was reported [88]. This method works via the co-crystal formation between (S)-BINOL and cis-(−)-lamivudine forming a binary complex which was characterised by single crystal X-ray crystallography. Raltegravir (3.18, Isentress), is another

Gold(I)-catalyzed enantioselective cycloaddition reactions

• Fernando López and
• José L. Mascareñas

Beilstein J. Org. Chem. 2013, 9, 2250–2264, doi:10.3762/bjoc.9.264

• substituents at the Binol ortho-positions (Au11, Scheme 9) [60]. Independently, Toste and co-workers reported that the related phosphoramidite–gold complex Au12, and the chiral gold catalyst Au13, derived from a C3-symmetric phosphite [66], were also able to induce excellent enantioselectivities in these [4

• active cyclobutanes [77]. Several chiral phosphoramidite–gold complexes, such as (S,R,R)-Au7, (S,R,R)-Au15 and (R,R,R)-Au16, derived from Siphos, Binol and Vanol, respectively, provided excellent enantioselectivities, displaying useful complementarity in some of the cases. Importantly, the method also

• Ph3PAuCl/AgNTf2 [79][80]. Moreover, for the latter cycloaddition with nitrones, the authors reported a enantioselective variant by using chiral phosphoramidite–gold complexes. In these cases, the binol-derived complexes, with aryl substituents at the 3 and 3’ positions, turned out to be the optimal systems

Synthesis of axially chiral gold complexes and their applications in asymmetric catalyses

• Yin-wei Sun,
• Qin Xu and
• Min Shi

Beilstein J. Org. Chem. 2013, 9, 2224–2232, doi:10.3762/bjoc.9.261

• Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, People’s Republic of China 10.3762/bjoc.9.261 Abstract Several novel chiral N-heterocyclic carbene and phosphine ligands were prepared from (S)-BINOL. Moreover, their ligated Au complexes

• . The synthesis of compound 9 was reported by Slaughter and co-workers (Scheme 1) [49]. The usage of (S)-BINOL as the starting material to react with trifluoromethanesulfonic anhydride in the presence of DIPEA afforded at 0 °C in dichloromethane the corresponding product (S)-2'-hydroxy-1,1'-binaphthyl-2

• indicated that no reaction occurred in the absence of a Au catalyst (Table 1, entry 14). Conclusion Axially chiral Au(I) complexes exhibiting a binaphthalene scaffold with NHC or phosphine gold complexes on one side and an arene moiety on another side were prepared starting from axially chiral BINOL. A weak

Organocatalytic asymmetric selenofunctionalization of tryptamine for the synthesis of hexahydropyrrolo[2,3-b]indole derivatives

• Qiang Wei,
• Ya-Yi Wang,
• Yu-Liu Du and
• Liu-Zhu Gong

Beilstein J. Org. Chem. 2013, 9, 1559–1564, doi:10.3762/bjoc.9.177

• ]. These leading findings indicate that either Lewis base or Brønsted acid shows catalytic activity for the selenofunctionalization reaction. Since chiral phosphoric acids have been shown to be Brønsted acid/Lewis base bifunctional organocatalysts [29][30][31][32][33], we ask whether the chiral BINOL-based