cas 75640-87-8, (S)-(-)-2,2'-Dimethoxy-1,1'-binaphthalene

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Enhancing the enantioselective recognition and sensing of chiral anions by halogen bonding
Chiral halogen bonding (S)-BINOL-based receptors are demonstrated to enhance the enantioselective recognition and sensing of chiral anions compared to their hydrogen bonding analogues. Computational studies attribute this behaviour to the strict linearity of halogen bonding (XB) and steric environment conferred by the XB donor groups bridged by the (S)-BINOL motif.
Lim, Jason Y. C.,Marques, Igor,Ferreira, Liliana,Félix, Vítor,Beer, Paul D.
p. 5527 - 5530
(2016)
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Unexpected self-assembly of chiral triangles from 90 chiral Di-Pt(II) acceptors
Two unexpected chiral organometallic triangles rather than squares from newly designed 90 chiral di-Pt(II) acceptors were obtained through coordination-driven self-assembly. Their structures were well characterized by multinuclear NMR (1H and 31P) and variable-temperature NMR experiments, ESI-TOF-MS, and elemental analysis. The PM6 semiempirical molecular simulation was employed for the interpretation of the formation and stability of such chiral triangles.
Ou-Yang, Jiang-Kun,Zhang, Yan-Yan,He, Meng-Lan,Li, Jiang-Tao,Li, Xiaopeng,Zhao, Xiao-Li,Wang, Cui-Hong,Yu, Yihua,Wang, De-Xian,Xu, Lin,Yang, Hai-Bo
p. 664 - 667
(2014)
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A Chiral, Dendralenic C-H Acid
We report the synthesis of a chiral dendralenic C H acid, which contains three unsubstituted binaphthyl moieties. This motif and an achiral variant can be made from their corresponding bis(sulfone) precursors in one step. Despite the presence of the enantiopure binaphthyl backbone, the newly designed chiral C H acid showed only poor enantioselectivity in a Mukaiyama aldol reaction. First attempts toward the synthesis of 3,3'-hexasubstituted binaphthyl-based dendralenic acids are also reported.
H?fler, Denis,List, Benjamin
supporting information
p. 38 - 39
(2021/12/29)

Palladium compound, preparation method thereof and preparation method of axially chiral biaromatic compound
The invention provides a palladium compound, a preparation method thereof and a preparation method of an axially chiral biaromatic compound. The invention discloses a compound shown as a formula IV ora formula IV', the palladium compound is novel in structure and suitable for coupling reaction, and the synthesized axially chiral biaryl compound is diversified in structure, high in yield and goodin stereoselectivity. The invention also discloses a preparation method of the axially chiral biaromatic compound, the axially chiral biaromatic compound prepared by the preparation method has the advantages of high yield, strong reaction stereoselectivity, wide substrate applicability and good applicability to heterocyclic substrates, the ee value can reach 85% or above, most of the ee value is 90% or above, and the substrate is wide in applicability and has very good applicability to heterocyclic substrates; the synthesized axially chiral biaromatic compound has various structures.
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Paragraph 0216; 0223; 0225; 0266

(2021/02/10)

Enantioselective cross-coupling for axially chiral tetra-ortho-substituted biaryls and asymmetric synthesis of gossypol
The axially chiral tetra-ortho-substituted biaryl skeleton exists in numerous biologically important natural products, pharmaceutical molecules, chiral catalysts, and ligands. The efficient synthesis of chiral tetra-ortho-substituted biaryl structures rem
Yang, He,Sun, Jiawei,Gu, Wei,Tang, Wenjun
supporting information
p. 8036 - 8043
(2020/05/27)

Enantioselective Ni-Catalyzed Electrochemical Synthesis of Biaryl Atropisomers
A scalable enantioselective nickel-catalyzed electrochemical reductive homocoupling of aryl bromides has been developed, affording enantioenriched axially chiral biaryls in good yield under mild conditions using electricity as a reductant in an undivided cell. Common metal reductants such as Mn or Zn powder resulted in significantly lower yields in the absence of electric current under otherwise identical conditions, underscoring the enhanced reactivity provided by the combination of transition metal catalysis and electrochemistry.
Chen, Song,Chen, Yue-Gang,Gao, Pei-Sen,Liu, Dong,Ma, Hong-Xing,Mei, Tian-Sheng,Qiu, Hui,Shuai, Bin,Wang, Yun-Zhao
supporting information
p. 9872 - 9878
(2020/06/27)

Synthesis of Chiral 3,3?-Disubstituted (S)-BINOL Derivatives via the Kumada and Suzuki Coupling and Their Antibacterial Activity
Abstract: A new series of 3,3?-disubstituted chiral (S)-BINOL derivatives 6a–6k has been synthesized viathe Kumada and Suzuki–Miyaura coupling reactions using (S)-BINOL as the initial compound. The Kumada coupling has beenfound to be superior in terms of
Ankireddy, A. Reddy,Paidikondala,Syed,Gundla,Reddy, Ch. Venkata Ramana,Ganapathi
p. 1507 - 1517
(2020/09/21)

A Bulky Chiral N-Heterocyclic Carbene Palladium Catalyst Enables Highly Enantioselective Suzuki-Miyaura Cross-Coupling Reactions for the Synthesis of Biaryl Atropisomers
Axially chiral biaryl scaffolds are essential structural units in chemistry. The asymmetric Pd-catalyzed Suzuki-Miyaura cross-coupling reaction has been widely recognized as one of the most practical methods for constructing atropisomers of biaryls. However, longstanding challenges remain in this field. For example, substrate scope is often narrow and specialized, functional groups and heterocycles can lead to reduced reactivity and selectivity, bulky ortho-substituents are usually needed, and reported methods are generally inapplicable to tetra-ortho-substituted biaryls. We have developed an unprecedented highly enantioselective N-heterocyclic carbene (NHC)-Pd catalyzed Suzuki-Miyaura cross-coupling reaction for the synthesis of atropisomeric biaryls. These reactions enable efficient coupling of aryl halides (Br, Cl) or aryl triflates with various types of aryl boron compounds (B(OH)2, Bpin, Bneo, BF3K), tolerate a remarkably broad scope of functional groups and heterocycles (>41 examples), employ low loading of catalyst (0.2-2 mol %), and proceed under mild conditions. The protocol provided general and efficient access to various atropisomeric biaryls and heterobiaryls in excellent enantioselectivities (up to 99% ee) with no need of using bulky ortho-substituted substrates and was effective for the synthesis of tetra-ortho-substituent biaryls. Moreover, the method was successfully applied to the diastereo- and enantioselective synthesis of atropisomeric ternaphthalenes. Critical to the success of the reaction is the development and application of an extremely bulky C2-symmetric chiral NHC, (R,R,R,R)-DTB-SIPE, as the ligand for palladium. To the best of our knowledge, this is the first highly enantioselective (>90% ee) example of a chiral NHC-metal-catalyzed C(sp2)-C(sp2) cross-coupling reaction.
Shen, Di,Xu, Youjun,Shi, Shi-Liang
supporting information
p. 14938 - 14945
(2019/10/11)

Enantioselective aryl-aryl coupling facilitated by chiral binuclear gold complexes
Herein, we report stoichiometric investigations embodying the first highly enantioselective aryl-aryl coupling facilitated by a gold complex. With up to 91% ee, this is the first demonstration of a transmetalation and C(sp2)-C(sp2) r
Himmelstrup, Jonas,Buendia, Mikkel B.,Sun, Xing-Wen,Kramer, S?ren
supporting information
p. 12988 - 12991
(2019/11/05)

Synthesis and catalytic activity of chiral dicarbene dipalladium complexes incorporating the S-binaphthol unit
A series of chiral di-N-heterocyclic carbene (NHC) dipalladium complexes, [{PdPyCl2}2(di-NHC)], in which di-NHC represents a diimidazolylidene, featuring an (S)-3,3'-dimethyl-2,2'-dimethoxy-1,1'-binaphthalene spacer between the carbene units, have been prepared. The influence of ligand size on the catalytic activity of these complexes in the Suzuki reaction of phenylboronic acid with p-bromotoluene has been investigated. The most sterically hindered complex, bearing the di-isopropylphenyl group, showed the greatest catalytic activity, and it is active for various aryl halides with different electronic and steric properties.
Zhang, Guowen,Chao, Man,Wang, Shuting,Zhu, Mengxia,Wang, Dou,Pang, Guangsheng,Shi, Yanhui
p. 54 - 56
(2018/02/28)

Enantioselective Anion Recognition by Chiral Halogen-Bonding [2]Rotaxanes
The application of chiral interlocked host molecules for discrimination of guest enantiomers has been largely overlooked, which is surprising given their unique three-dimensional binding cavities capable of guest encapsulation. Herein, we combined the stringent linear geometric interaction constraints of halogen bonding (XB), the noncovalent interaction between an electrophilic halogen atom and a Lewis base, with highly preorganized and conformationally restricted chiral cavities of [2]rotaxanes to achieve enantioselective anion recognition. Representing the first detailed investigation of the use of chiral XB rotaxanes for this purpose, extensive 1H NMR binding studies and molecular dynamics (MD) simulation experiments revealed that the chiral rotaxane cavity significantly enhances enantiodiscrimination compared to the non-interlocked free axle and macrocycle components. Furthermore, by examining the enantioselectivities of a family of structurally similar XB [2]rotaxanes containing different combinations of chiral and achiral macrocycle and axle components, the dominant influence of the chiral macrocycle in our rotaxane design for determining the effectiveness of chiral discrimination is demonstrated. MD simulations reveal the crucial geometric roles played by the XB interactions in orientating the bound enantiomeric anion guests for chiral selectivity, as well as the critical importance of the anions' hydration shells in governing binding affinity and enantiodiscrimination.
Lim, Jason Y. C.,Marques, Igor,Félix, Vítor,Beer, Paul D.
supporting information
p. 12228 - 12239
(2017/09/12)

Synthesis of optically active poly(diphenylacetylene)s using polymer reactions and an evaluation of their chiral recognition abilities as chiral stationary phases for HPLC
A series of optically active poly(diphenylacetylene) derivatives bearing a chiral substituent (poly-2S) or chiral and achiral substituents (poly-(2Sx-co-31-x)) on all of their pendant phenyl rings were synthesized by the reaction of poly(bis(4-carboxyphenyl)acetylene) with (S)-1-phenylethylamine ((S)-2) or benzylamine (3) in the presence of a condensing reagent. Their chiroptical properties and chiral recognition abilities as chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) were investigated. Poly-2S and poly-(2Sx-co-31-x) (0.06 x-co-31-x)). Furthermore, h-poly-2S and h-poly-(2S0.36-co-30.64) emitted circularly polarized luminescence with opposite signs. h-Poly-2S showed higher chiral recognition abilities toward a larger number of racemates than poly-2S without a preferred-handed helicity and the previously reported preferred-handed poly(diphenylacetylene) derivative bearing the same chiral substituent on half of its pendant phenyl rings. h-Poly-(2S0.36-co-30.64) also exhibited good chiral recognition abilities toward several racemates, though the elution order of some enantiomers was reversed compared with h-poly-2S.
Maeda, Katsuhiro,Maruta, Miyuki,Sakai, Yuki,Ikai, Tomoyuki,Kanoh, Shigeyoshi
(2016/12/03)

An enantioselective artificial Suzukiase based on the biotin-streptavidin technology
Introduction of a biotinylated monophosphine palladium complex within streptavidin affords an enantioselective artificial Suzukiase. Site-directed mutagenesis allowed the optimization of the activity and the enantioselectivity of this artificial metalloenzyme. A variety of atropisomeric biaryls were produced in good yields and up to 90% ee. The hybrid catalyst described herein shows comparable TOF to the previous aqueous-asymmetric Suzuki catalysts, and excellent stability under the reaction conditions to realize higher TON through longer reaction time.
Chatterjee, Anamitra,Mallin, Hendrik,Klehr, Juliane,Vallapurackal, Jaicy,Finke, Aaron D.,Vera, Laura,Marsh, May,Ward, Thomas R.
p. 673 - 677
(2015/12/30)

Macromolecular helicity induction and memory in a poly(biphenylylacetylene) bearing an ester group and its application to a chiral stationary phase for high-performance liquid chromatography
An optically inactive poly(biphenylylacetylene) bearing an ester group at the 4′-position of the pendants formed a preferred-handed helical conformation and biased axial chirality in the pendants through a noncovalent interaction with a chiral alcohol, both of which were retained (memorized) even after removal of the chiral alcohol. The chiral stationary phase for high-performance liquid chromatography, prepared by coating the polymer with macromolecular helicity memory on silica gel, showed good chiral recognition ability towards various racemates.
Ishidate, Ryoma,Shimomura, Kouhei,Ikai, Tomoyuki,Kanoh, Shigeyoshi,Maeda, Katsuhiro
p. 946 - 948
(2015/08/24)

Solvent Molding of Organic Morphologies Made of Supramolecular Chiral Polymers
The self-assembly and self-organization behavior of uracil-conjugated enantiopure (R)- or (S)-1,1′-binaphthyl-2,2′-diol (BINOL) and a hydrophobic oligo(p-phenylene ethynylene) (OPE) chromophore exposing 2,6-di(acetylamino)-pyridine termini are reported. S
Dordevi?, Luka,Marangoni, Tomas,Mileti?, Tanja,Rubio-Magnieto, Jenifer,Mohanraj, John,Amenitsch, Heinz,Pasini, Dario,Liaros, Nikos,Couris, Stelios,Armaroli, Nicola,Surin, Mathieu,Bonifazi, Davide
supporting information
p. 8150 - 8160
(2015/07/08)

Highly sterically hindered binaphthalene-based monophosphane ligands: Synthesis and application in stereoselective Suzuki-Miyaura reactions
A series of new sterically hindered (R)-(2′-aryl-1,1′- binaphthalene-2-yl)phosphanes with ortho-substituted phenyls as aryl groups were prepared via Negishi monoarylation of enantiopure 2,2′-dibromo-1, 1′-binaphthalene followed by lithiation and quenching with diphenylphosphanyl or dicyclohexylphosphanyl chloride. These ligands were applied to the stereoselective Suzuki-Miyaura coupling for the preparation of substituted biaryls. The enantioselectivity correlated positively when increasing the hindrance of the 2′-aryl group of the ligand. Using the best performing diphenylphosphane ligand with a 2,6-dimethoxyphenyl aryl group, various arylnaphthalenes were prepared in high to excellent yields (68-99%) with low to good ee (12-75% ee), the latter being comparable to the best values reported when using other chiral monophosphane ligands.
Meskova, Michaela,Putala, Martin
p. 894 - 902
(2013/09/23)

Antimony(V) chloride as an efficient reagent for deprotection of methyl ethers
This paper proposes a new and efficient method for the deprotection of methyl ethers using antimony pentachloride at ambient temperature. The procedure described here is a facile and practical method for the removal of the methyl group from aryl and benzyl methyl ethers. High selectivity was observed for the removal of the methyl group from dimethoxyarenes. The notable advantages of this protocol are mild reaction conditions, high yields, and the facility of workup procedure. The mechanism of the ether cleavage is proposed to explain this new reaction. Georg Thieme Verlag Stuttgart New York.
Saadati, Fariba,Meftah-Booshehri, Hamid
p. 1702 - 1706
(2013/09/02)

BINOL-fused maleimides - A new class of C2-symmetric chiral imides
The first synthesis of BINOL-fused maleimides has been developed. This new chiral scaffold is easily accessible from various BINOL analogues and 2,3-dihalomaleimide derivatives under basic conditions. It can be easily functionalized on the BINOL moiety an
Brenet, Simon,Baptiste, Benoit,Philouze, Christian,Berthiol, Florian,Einhorn, Jacques
supporting information
p. 1041 - 1045
(2013/04/23)

Solution-phase synthesis and evaluation of tetraproline chiral stationary phases
A protocol was developed for the solution-phase synthesis of multigram amounts of two 9-fluorenylmethoxycarbonyl (Fmoc)-protected tetraproline peptides. These tetraproline peptides were then attached to amino derivatized silica gel. The replacement of the Fmoc group with the trimethylacetyl group lead to two tetraproline chiral stationary phases (CSPs). A comparison of the chromatographic behavior of these two solution-phase-synthesized tetraproline CSPs with that prepared by stepwise solid-phase synthesis revealed that all three had similar chromatographic performance for resolving 53 model analytes. This suggests that the solution-phase synthesis of oligoprolines, which allows for the specific benefits of good batch reproducibility, selector homogeneity, and possibly low cost, is a feasible alternative to the solid-phase synthesis of oligoproline CSPs. Copyright
Dai, Zhi,Ye, Guozhong,Pittman Jr., Charles U.,Li, Tingyu
experimental part
p. 329 - 338
(2012/05/20)

A highly sensitive water-soluble system to sense glucose in aqueous solution
A glucose sensing switch is formed by water soluble conjugated polymer (PP-S-BINOL) and boronic acid-functionalized benzyl viologen (o-BBV). The two-component system shows a high sensitivity for glucose sensing with a 17-fold increase in the fluorescence intensity in the presence of 100 mM glucose.
Feng, Liheng,Liang, Fei,Wang, Yue,Xu, Ming,Wang, Xiaoju
scheme or table
p. 2938 - 2942
(2011/05/06)

Highly selective recognition of monosaccharide based on two-component system in aqueous solution
A highly selective switch for d-fructose was formed by water-soluble conjugated polymer PP-S-BINOL and tetraboronic acid functionalized benzyl viologen ToBV. The two-component system showed a high selectivity and sensitivity only for d-fructose in familiar d-monosaccharides. The high selectivity of the sensing system for d-fructose may be depended on stable pyranose ester form of d-fructose with ToBV. A desirable linear response of the sensing system to low concentrations of d-fructose (10.0 mM) was observed with 0.9936 linear dependent coefficient at pH 7.4.
Feng, Liheng,Wang, Yue,Liang, Fei,Xu, Ming,Wang, Xiaoju
experimental part
p. 3175 - 3180
(2011/05/17)

Catalytic asymmetric bromine-lithium exchange: A new tool to build axial chirality
We present here the first catalytic desymmetrization of the 2,2′,6,6′-tetrabromobiphenyl 1 and analogues, by a bromine-lithium exchange catalyzed by either diamines or diether derivatives (0.5 equiv.), yielding axially chiral compounds in high yield (up to 89%) and high enantioselectivity (up to 82%).
Perron, Quentin,Alexakis, Alexandre
supporting information; experimental part
p. 2611 - 2620
(2011/01/05)

Copper-catalyzed enantioselective conjugate addition of Grignard reagents to acyclic enones using monodentate phosphoramidite ligands
Herein, we report efficient catalysts based on phosphoramidites for the asymmetric copper-catalyzed conjugate addition of Grignard reagents to acyclic α,β-unsaturated ketones. A variety of Grignard reagents can be added to aliphatic and aromatic acyclic e
Maciá, Beatriz,Fernández-Ibá?ez, M. ángeles,Mr?i?, Nata?a,Minnaard, Adriaan J.,Feringa, Ben L.
p. 1877 - 1880
(2008/09/18)

Asymmetric Negishi reaction for sterically hindered couplings: synthesis of chiral binaphthalenes
A new synthetic approach affording, for the first time chiral binaphthalene derivatives via an asymmetric Negishi reaction, in good yields (55-95%) and good enantioselectivities (49-85% ee), is reported.
Genov, Miroslav,Fuentes, Beatriz,Espinet, Pablo,Pelaz, Beatriz
p. 2593 - 2595
(2007/10/03)

Supported Chiral Mo-Based Complexes as Efficient Catalysts for Enantioselective Olefin Metathesis
Syntheses and catalytic activities of seven new polymer-supported chiral Mo-based complexes are disclosed. Four of the complexes are polystyrene-based, and three involve polynorbornene supports. Studies concerning the ability of the polymer-bound chiral c
Dolman, Sarah J.,Hultzsch, Kai C.,Pezet, Frederic,Teng, Xin,Hoveyda, Amir H.,Schrock, Richard R.
p. 10944 - 10953
(2007/10/03)

Properties of a binaphthyl-bridged porphyrin - Iron complex bearing hydroxy groups inside its cavity
Hydrogen-bond formation with the terminal oxygen atom is considered to be the basis of dioxygen molecule activation by cytochrome P450. In order to verify the effect of this hydrogen bond, we have undertaken the synthesis of a model complex: a binaphthyl-
Kossanyi, Alain,Tani, Fumito,Nakamura, Nobu,Naruta, Yoshinori
p. 2862 - 2872
(2007/10/03)

HPLC enantioseparation with cellulose tris(3,5-dichlorophenylcarbamate) in aqueous methanol as a mobile phase
The appropriate design of mobile and stationary phase combinations allowed the use of cellulose tris(3,5-dichlorophenylcarbamate) (CDCPC) as the chiral stationary phase (CSP) in high-performance liquid chromatography (HPLC). Together with previous data obtained in n-hexane/2-propanol as a mobile phase the present study indicates very high chiral resolving ability of CDCPC.
Chankvetadze, Bezhan,Yamamoto, Chiyo,Okamoto, Yoshio
p. 352 - 353
(2007/10/03)

Enantioselective catalytic conjugate addition of dialkylzinc reagents using copper-phosphoramidite complexes; ligand variation and non-linear effects
A variety of new chiral phosphoramidites was synthesised and tested in the copper-catalysed enantioselective conjugate addition of diethylzinc to cyclohexenone and chalcone in order to assess the structural features that are important for stereocontrol. A
Arnold, Leggy A.,Imbos, Rosalinde,Mandoli, Alessandro,De Vries, André H.M.,Naasz, Robert,Feringa, Ben L.
p. 2865 - 2878
(2007/10/03)

Formal total synthesis of (+)-diepoxin σ
The highly oxygenated antifungal anticancer natural product (±)-diepoxin σ was prepared in 10 steps and in 15% overall yield from O-methylnaphthazarin. Highlights of the synthetic work include an Ullmann coupling and a possibly biomimetic oxidative spirocyclization for the introduction of the naphthalene ketal as well as the use of a retro-Diels-Alder reaction to unmask the reactive enone moiety in the naphthoquinone bisepoxide ring system. A novel highly bulky chiral binaphthol ligand was developed for a boron-mediated Diels-Alder reaction that constitutes a formal asymmetric total synthesis of (+)-diepoxin σ.
Wipf, Peter,Jung, Jae-Kyu
p. 6319 - 6337
(2007/10/03)

Enantioselective synthesis of binaphthol derivatives by oxidative coupling of naphthol derivatives catalyzed by chiral diamine-copper complexes
A highly efficient process of aerobic oxidative coupling of 2-naphthol derivatives catalyzed by 1 mol % of Cu(OH)Cl·TMEDA has been developed. Enantioselective oxidative coupling of naphthols was achieved by the use of 10 mol % of chiral catalysts prepared from proline-derived diamines and cuprous chloride, affording the corresponding binaphthols in good enantioselectivities of up to 78% ee. The ester moiety at the 3-position of the substrate was found to be essential for the good asymmetric induction observed in the present coupling reaction.
Nakajima, Makoto,Miyoshi, Irie,Kanayama, Kumiko,Hashimoto, Shun-Ichi,Noji, Masahiro,Koga, Kenji
p. 2264 - 2271
(2007/10/03)

Synthesis of Enantiomerically Pure Thiocrown Ethers Derived from 1,1'-Binaphthalene-2,2'-diol
Synthetic methodology is given for the preparation of two different types of thiocrown ethrs from optically pure 1,1'-binaphthalene-2,2'-diol (10).The conceptually simplest approach starts from optically pure 10 itself, which is alkylated (4 equiv of K2CO3 in DMF at 110 deg C) with 2-chloroethanol followed by mesylation to provide 2,2'-bis(2-mesyloxy)ethoxy)-1,1'-binaphthyl (14).When allowed to react with ethane-1,2-dithiol, propane-1,3-dithiol, 1,4,7--trithiaheptane, 1,4,8,11-tetrathiaundecane, 2,2-dimethylpropane-1,3-dithiol, 2-(mercaptomethyl)-1-propene-3-thiol, and 1,2-benzenedithiol in the presence of Cs2CO3 in DMF at 60 deg C the corresponding thiocrown ethers 22-25, 28, 30, and 32 are formed in 30-54percent yields.Test reactions were carried out to establish that no racemization occurs during alkylation under these conditions.Reaction of optically pure 10 with tetrahydropyranyl (THP)-protected 3-chloropropanol under similar conditions for the preparation of 14 proceeded more sluggishly but cleanly.Removal of the THP protecting groups afforded 2,2'-bis(3-bromopropoxy)-1,1'-binaphthyl (20), which on reaction with propane-1,3-dithiol, 1,5,9-trithianonane, 2,2-dimethylpropane-1,3-dithiol, 2-(mercaptomethyl)-1-propene-3-thiol, and 1,2-bis(mercaptomethyl)benzene provided the respective thiocrown ethers 26, 27, 29, 31, and 33 in 24-68percent yields.Another class of thiocrown ethers was prepared from optically active 10, which converted via ortho-lithiation to 3,3'-bis(bromomethyl)-2,2'-dimethoxy-1,1'-binaphthyl (39) by means of methylation (K2CO3/CH3I)), ortho-lithiation followed by formylation (n-C4H9Li/N,N,N',N'-tetramethylethylenediamine (TMEDA)/ether followed by DMF and H2O workup) followed by reduction (NaBH4) followed by bromination (PBr3 in C5H5N).Reaction (Cs2CO3 in DMF at 60 deg C) with 1,4,7-trithiaheptane, 1,4,8-trithiaoctane, 1,4,7,10-tetrathiadecane, 1,4,8,11-tetrathiaundecane, and 1,5,10,14-tetrathiatetradecane afforded the corresponding thiocrown ethers 40-44 in 40-75percent yields.Despite repeated attempts using a wide range of reagents, demethylation of the methoxy ether functionalities failed.Attempts to prepare the free phenol derivatives of the latter type of grown ethers by oxuidative coupling of two naphthol units failed.
Stock, H. Thijs,Kellogg, Richard M.
p. 3093 - 3105
(2007/10/03)

Enantioselective, Electrocatalytic Oxidative Coupling of Naphthol, Naphthyl Ether and Phenanthrol on a TEMPO-modified Graphite Felt Electrode in the Presence of (-)-Sparteine (TEMPO = 2,2,6,6-tetramethylpiperidin-1-yloxyl)
Constant potential electrolysis of 2-naphthol, 2-methoxynaphthalene and 10-hydroxyphenanthrene at 0.6 V vs.Ag/AgCl on a TEMPO-modified graphite felt electrode in the presence of (-)-sparteine in acetonitrile yields, enantioselectively, (S)-binaphthyl type dimers in > 92percent isolated yield and with > 88percent current efficiency with enantiomeric excess of 98, 91 and 97percent respectively for each dimer, respectively.
Osa, Tetsuo,Kashiwagi, Yoshitomo,Yanagisawa, Yoshinori,Bobbitt, James M.
p. 2535 - 2538
(2007/10/02)

Spontaneous Resolution of 2,2'-Dimethoxy-1,1'-binaphthalene
The dimethyl ether of 1,1'-bi-2-naphthol crystallizes as a conglomerate and can be resolved without chiral auxiliaries by entrainment.The direct crystallization of a supersaturated solution of the title compound partially enriched by one enantiomer (ee ca. 2percent) is conducted in anisole at 40 deg C and gives, after one crystallization, a compound with ee >98percent.Demethylation under nonracemizing conditions gives the enantiomeric 1,1'-bi-2-naphthol.
Gottarelli, Giovanni,Spada, Gian Piero
p. 2096 - 2098
(2007/10/02)

Host-Guest Complexation. 23. High Chiral Recognition of Amino Acid and Ester Guests by Hosts Containing One Chiral Element
The chiral recognition properties of ten enantiomerically pure hosts toward the enantiomers of six different amino acids and their methyl esters have been examined.The hosts possessed the general structure (A)2D(OEOEO)2E, in which D is the chiral 1,1'-din
Lingenfelter, David S.,Helgeson, Roger C.,Cram, Donald J.
p. 393 - 406
(2007/10/02)