- Enantioselective iron/bisquinolyldiamine ligand‐catalyzed oxidative coupling reaction of 2‐naphthols
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An iron‐catalyzed asymmetric oxidative homo‐coupling of 2‐naphthols for the synthesis of 1,1′‐Bi‐2‐naphthol (BINOL) derivatives is reported. The coupling reaction provides enantioenriched BINOLs in good yields (up to 99%) and moderate enantioselectivities (up to 81:19 er) using an iron‐complex generated in situ from Fe(ClO4)2 and a bisquinolyldiamine ligand [(1R,2R)‐N1,N2‐di(quinolin‐8‐yl)cyclohexane‐1,2‐diamine, L1]. A number of ligands (L2–L8) and the analogs of L1, with various substituents and chiral backbones, were synthesized and examined in the oxidative coupling reactions.
- Liu, Wen-Bo,Usman, Muhammad,Wu, Lin-Yang
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- Organocatalytic Enantioselective Synthesis of Atropisomeric Aryl-p-Quinones: Platform Molecules for Diversity-Oriented Synthesis of Biaryldiols
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Presented here is a class of novel axially chiral aryl-p-quinones as platform molecules for the preparation of non-C2 symmetric biaryldiols. Two sets of aryl-p-quinone frameworks were synthesized with remarkable enantiocontrol by means of chiral phosphoric acid catalyzed enantioselective arylation of p-quinones by central-to-axial chirality conversion. These aryl-p-quinones were then used to access a wide spectrum of highly functionalized non-C2 symmetric biaryldiols with excellent retention of the enantiopurity.
- Chen, Ye-Hui,Li, Heng-Hui,Li, Shaoyu,Tan, Bin,Xiang, Shao-Hua,Zhang, Xiao
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p. 11374 - 11378
(2020/05/25)
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- Lewis Acid-Mediated Cyanation of Phenols Using N-Cyano-N-phenyl-p-toluenesulfonamide
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Lewis acid-mediated cyanation of phenol derivatives with N-cyano-N-phenyl-p-toluenesulfonamide (NCTS) has been developed. The reaction proceeded efficiently with high regioselectivity to produce aromatic nitriles in moderate to excellent yields, which provides a direct and practical access to valuable products. (Figure presented.).
- Zhang, Wu,Li, Tao,Wang, Qingli,Zhao, Wanxiang
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supporting information
p. 4914 - 4918
(2019/11/03)
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- Unsymmetrical banana-shaped liquid crystalline compounds derived from 2,7-dihydroxynaphthalene
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The synthesis and characterization of new asymmetric bent-core compounds derived from 2,7-dihydroxynaphthalene with various connecting groups between the aromatic rings and alkyloxy terminal substituents at the end of the long arm are presented. Some 1,4-disubstituted phenylene rings with an azo or ester linkage between them have been used as calamitic pro-mesogen units. The synthetic strategies to obtain the final esteric derivatives involved the esterification of 7-(benzyloxy)naphthalen-2-ol with 4-((4-(alkyloxy)phenyl)-azo)benzoyl chlorides or with 4-((4-(alkyloxy)benzoyl)oxy)benzoic acids in the presence of dicyclohexylcarbodiimide (DCC) and 4-(dimethylamino)pyridine (DMAP). The mesomorphic properties were assigned by optical polarizing microscopy and differential scanning calorimetry. All the compounds showed mesomorphic properties of the enantiotropic or monotropic type, the liquid crystalline behavior depending on the linking group between the phenylene rings. Thermogravimetric studies evidenced that all compounds were stable in the range of the existence of mesophases.
- Simion, Aurel,Huzum, Cosmin-Constantin,Carlescu, Irina,Lisa, Gabriela,Balan, Mihaela,Scutaru, Dan
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p. 673 - 683
(2015/08/24)
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- Regioselective O-alkylations and acylations of polyphenolic substrates using a calix[4]pyrrole derivative
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The 10α,20α-bis(4-nitrophenyl)-calix[4]pyrrole 2 can act as a topologically selective protecting group in the O-alkylation and acylation of polyphenolic polycyclic aromatic compounds thanks to the regioselective formation of phenolate-type complexes. Rema
- Cafeo, Grazia,Kohnke, Franz H.,Valenti, Luca
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experimental part
p. 4138 - 4140
(2009/12/06)
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- A novel molecular cleft based on dioxocin ring, part I: Synthesis and conformational analysis
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The Molecular cleft 1 using 8-methyl-16H-dinaphtho[2,1-d:1,2-g][1,3]dioxocin-2,14-diol as a spacer was synthesized. Density functional calculations at B3LYP/6-31G level of theory indicates that 8-methyl-16H-dinaphtho[2,1-d:1,2-g][1,3]dioxocin, the central
- Vafakish, Bahareh,Rashidi-Ranjbar, Parviz
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experimental part
p. 2741 - 2753
(2010/04/25)
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- Linker-oriented design of binaphthol derivatives for optical resolution using lipase-catalyzed reaction
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(Chemical Equation Presented) Candida antarctica lipase B (CAL-B) is one the most frequently used enzymes in organic synthesis for the preparation of optically active alcohols. However, it has not been used for the optical resolution of (±)-2,2′-binaphthol. We established an efficient linker-oriented design of 2,2′-binaphthol derivatives that is appropriate for optical resolution using CAL-B-catalyzed hydrolysis reaction. Methyl 4-(1-(6-bromo-2-methoxymethoxynaphthalen-1-yl)-6-bromonaphthalen-2-yloxy) butanoate was hydrolyzed by CAL-B to afford a corresponding acid with excellent enantioselectivity (E > 200). Two types of optically active binaphthol derivatives, 1-(2-hydroxy-6-(naphthalen-1-yl)naphthalen-1-yl)-6-(naphthalen-1- yl)naphthalen-2-ol and 6-butyl-1-(6-butyl-2-hydroxynaphthalen-1-yl)naphthalen-2- ol, were prepared by this chemoenzymatic reaction protocol and were used as chiral templates for symmetric reactions.
- Taniguchi, Tomohiro,Fukuba, Taka-Aki,Nakatsuka, Shuhei,Hayase, Shuichi,Kawatsura, Motoi,Uno, Hidemitsu,Itoh, Toshiyuki
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p. 3875 - 3884
(2008/09/20)
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- 1-ALKYNYL-2-ARYLOXYALKYLAMIDES AND THEIR USE AS FUNGICIDES
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Compounds of the formula wherein the substituents are as defined in the claims, are useful as fungicides.
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Page/Page column 41
(2008/06/13)
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- Liquid crystalline properties of unsymmetrical bent-core compounds containing chiral moieties
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The synthesis, characterization and mesomorphic properties of new unsymmetrical bent-core compounds containing chiral moieties are reported. These compounds have been derived from either 3-hydroxybenzoic acid or 2,7-dihydroxynaphthalene as the central unit. The chiral group is incorporated either within the bent-core structure as a linking group or is appended in the terminal position. The influence of the position of the chiral moiety on the mesomorphic properties has been investigated. The bent-core compounds containing a chiral group (octan-2-ol) in the terminal chain exhibit a direct transition from chiral calamitic phases such as SmC*, SmC*γ to a polar banana phase with a two-dimensional lattice (ColobP A*) on decreasing temperature. In order to prove this phase sequence, the corresponding compound with a racemic octan-2-ol group at the terminal chain has been synthesized. The preliminary observations and investigations are presented for comparison with the chiral compound. Possible explanations for this unusual phase sequence and the models for the Col obPA* (SmCsPA*) phase are also discussed on the basis of X-ray and electric field experiments. The Royal Society of Chemistry 2005.
- Reddy, R. Amaranatha,Sadashiva,Baumeister
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p. 3303 - 3316
(2007/10/03)
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- A modular route to nonracemic cyclo-NOBINs. Preparation of the parent ligand for homo- and heterogeneous catalysis
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A sequence which combines a nonracemic tether, a naphthyl diol, and an aminonaphthol has been developed leading to the new ligand cyclo-NOBIN, which can easily be mounted onto polystyrene. Opportunities for extending the route to substituted cyclo-NOBINs are also discussed.
- Lipshutz, Bruce H.,Buzard,Olsson, Christina,Noson, Kevin
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p. 4443 - 4449
(2007/10/03)
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- Synthesis and pharmacological analysis of high affinity melatonin receptor ligands
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We report the synthesis and radioligand binding analysis of a series of naphthalenic melatonin receptor ligands, N-[2-(7-alkoxy-2-methoxy-1-naphthyl) ethyl]propionamide. This series of ligands exhibits subpicomolar binding affinity to both MT1
- Chu, Guo-Hua,Witt-Enderby, Paula A.,Jones, Marla,Li, Pui-Kai
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p. 272 - 275
(2007/10/03)
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- Highly diastereoselective synthesis of the 1,1'-binaphthol unit on a bile acid template
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The use of 7-deoxycholic acid as a chiral template in the asymmetric syntheses of 1,1'-binaphthyl-2,2'-diol derivatives is reported. Intramolecular coupling of compounds 7 and 11 have been carried out with Mn(acac)3 in CH3CN to afford coupled binaphthol products 8 and 12 with 65% and >99% diastereoselectivity, respectively. In both cases the predominant formation of the (S) isomers were predicted by computer modeling studies. This was confirmed in the case of compound 12.
- Bandyopadhyaya,Sangeetha,Maitra
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p. 8239 - 8244
(2007/10/03)
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- Synthesis of (R)- and (S)-7,7'-Bis(diphenylphosphino)-2,2'-dimethoxy-1,1'-binaphthyl, a New Axially Dissymmetric Bis(triarylphosphine)
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A new axially dissymmetric bis(triarylphosphine) ligand 7,7'-bis(diphenylphosphino)-2,2'-dimethoxy-1,1'-binaphthyl has been synthesized in enantiomerically pure form.
- Horiuchi, Toshihide,Ohta, Tetsuo,Stephan, Massoud,Takaya, Hidemasa
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p. 325 - 328
(2007/10/02)
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