- Synthesis of Chiral Propargylamines, Chiral 1,2-Dihydronaphtho[2,1-b]furans and Naphtho[2,1-b]furans with C-Alkynyl N,N′-di-(tert-butoxycarbonyl)-aminals and β-Naphthols
-
Chiral phosphoric acid-catalyzed couplings of C-alkynyl N,N′-di-(tert-butoxycarbonyl)-aminals with β-naphthols led to chiral propargylamines in moderate to high yields with high to excellent enantioselectivity, in which the reactions underwent sequential chiral phosphoric acid-catalyzed in situ formation of N-(tert-butoxycarbonyl)-imines (N-Boc-imines) from the aminals, and 1,2-addition of β-naphthols to the N-Boc-imines. Chiral 1,2-dihydronaphtho[2,1-b]furans and naphtho[2,1-b]furans were prepared with satisfactory results when 10 mol% AgOAc and 20 mol% 2,6-lutidine or 1.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) were added to the resulting chiral propargylamines solution, respectively.
- Man, Ningning,Li, Yuming,Jie, Jiyang,Li, Hongyun,Yang, Haijun,Zhao, Yufen,Fu, Hua
-
supporting information
p. 12884 - 12889
(2021/07/28)
-
- SMALL MOLECULE INHIBITORS OF A PROTEIN COMPLEX
-
Compositions and methods for treating thrombosis, inflammation, and atherosclerosis by administration of a compound that binds to KRIT1 to inhibit binding with HEG1.
- -
-
Paragraph 00165
(2020/12/29)
-
- Organocatalytic Enantioselective Synthesis of Atropisomeric Aryl-p-Quinones: Platform Molecules for Diversity-Oriented Synthesis of Biaryldiols
-
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
-
supporting information
p. 11374 - 11378
(2020/05/25)
-
- 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)
-
- Ligand-controlled regiodivergent π-allyl palladium catalysis enables a switch between [3+2] and [3+3] cycloadditions
-
Reported herein is the use of ligands to tune the regioselectivity and reactivity of palladium-catalyzed [3+2] and [3+3] cycloadditions. Diverse synthesis with vinylethylene carbonates (VECs) as well as free naphthols has been explored to construct four different valuable polycyclic frameworks in a broad substrate scope.
- Xia, Yu,Bao, Qiao-Fei,Li, Yuke,Wang, Li-Jing,Zhang, Bo-Sheng,Liu, Hong-Chao,Liang, Yong-Min
-
supporting information
p. 4675 - 4678
(2019/05/02)
-
- Annulation of β-naphthols and 4-hydroxycoumarins with vinylsulfonium salts: Synthesis of dihydrofuran derivatives
-
A new synthetic approach to dihydrofuran derivatives via the annulation reaction of β-naphthols and 4-hydroxycoumarins with vinylsulfonium salts has been developed. A variety of dihydrofuran derivatives were prepared in moderate to good yields under mild conditions. The products could be readily transformed to the corresponding furans via the dehydrogenation with DDQ.
- Chen, Zi-Cong,Tong, Lang,Du, Zhi-Bo,Mao, Zhi-Feng,Zhang, Xue-Jing,Zou, Yong,Yan, Ming
-
supporting information
p. 2634 - 2638
(2018/04/26)
-
- Enantioselective Oxidative Homocoupling and Cross-Coupling of 2-Naphthols Catalyzed by Chiral Iron Phosphate Complexes
-
Novel chiral iron phosphate complexes were prepared as catalysts for asymmetric oxidative coupling reactions. These catalysts were applied for the synthesis of enantio-enriched C1- and C2-symmetric BINOLs, in which the 3 and 3′ positions are available for chemical modifications. It was proposed that the reaction takes place via an oxidative radical-anion coupling mechanism. A destructive BINOL racemization that competes with the enantioselective oxidative coupling of 2-naphthols was revealed, thereby offering new insights into this highly important reaction.
- Narute, Sachin,Parnes, Regev,Toste, F. Dean,Pappo, Doron
-
supporting information
p. 16553 - 16560
(2016/12/27)
-
- Iron-Catalyzed C-Allylating Partial Dearomatization of Naphthols
-
The iron complex Bu4N[Fe(CO)3(NO)] (TBA[Fe]) catalyzes the intermolecular allylation of naphthol derivatives to give the corresponding partially dearomatized allylated chromenones in good to excellent yields. The scope and limitations are reported. An efficient decarboxylative intramolecular C-allylation, starting from allyl naphthyl carbonates, was developed. From a mechanistic point of view, the overall process is the result of a fast O-allylation followed by a sigmatropic rearrangement to the desired product.
- Heid, Berenice,Plietker, Bernd
-
supporting information
p. 340 - 350
(2016/01/28)
-
- Simple and efficient one-step conversion of benzonitrile into methylarene under mild conditions
-
A very simple and efficient method has been developed for the synthesis of various methylarenes from the corresponding benzonitriles under mild conditions. The protocol uses Pearlmans catalyst to achieve the transformation under an atmosphere of gaseous hydrogen and proceeds smoothly in many common solvents. A series of methylarenes were thus obtained in high yields and purities. Georg Thieme Verlag Stuttgart - New York.
- Ouellet, étienne,Poirier, Donald
-
experimental part
p. 2025 - 2028
(2011/10/12)
-
- Protecting group free synthesis of 6-substituted naphthols and binols
-
A straightforward route for the preparation of 6-substituted naphthols and 6,6′-disubstituted binols (binol = 2,2′-dihydroxy-1,1′- binaphthyl) is presented. The synthesis has been accomplished by a one-step procedure starting from 6-bromo derivatives via direct lithiation with n-BuLi, followed by the addition of several electrophiles. This C-C functionalization has been successfully achieved with iodomethane, 3-methoxybenzaldehyde, benzophenone, methyl-2-methylbenzoate, methylbenzoate, dimethyl carbonate, ethyl 2-chloro-2-oxoacetate, and 2,2-dimethyloxirane (E). This reactivity offers a useful protecting group free synthetic protocol, toward chiral disubstituted 6,6′-binols with configuration retention of the binol moiety.
- Verga, Daniela,Percivalle, Claudia,Doria, Filippo,Porta, Alessio,Freccero, Mauro
-
supporting information; experimental part
p. 2319 - 2323
(2011/05/14)
-
- Photogeneration and reactivity of naphthoquinone methides as purine selective DNA alkylating agents
-
A one-step protecting-group-free synthesis of both 6-hydroxy-naphthalene-2- carbaldehyde and the bifunctional binaphthalenyl derivative afforded 6-hydroxymethylnaphthalen-2-ol, 6-methylaminomethyl-naphthalen-2-ol, [(2-hydroxy-3-naphthyl)methyl]trimethyl ammonium iodide, and a small library of bifunctional binol analogues in good yields. Irradiation of naphthol quaternary ammonium salt and binol-derivatives (X = OH, NHR, NMe3+, OCOCH3, and l-proline) at 310 and 360 nm resulted in the photogeneration of the 2,6-naphthoquinone-6-methide (NQM) and binol quinone methide analogues (BQMs) by a water-mediated excited-state proton transfer (ESPT). The hydration, the mono- and bis-alkylation reactions of morpholine and 2-ethanethiol, as N and S prototype nucleophiles, by the transient NQM (λmax 310, 330 nm) and BQMs (λmax 360 nm) were investigated in water by product distribution analysis and laser flash photolysis (LFP). Both the photogeneration and the reactivity of NQM and BQMs exhibited striking differences. BQMs were at least 2 orders of magnitude more reactive than NQM, and they were generated much more efficiently from a greater variety of photoprecursors including the hydroxymethyl, quaternary ammonium salt and several binol-amino acids. On the contrary, the only efficient precursor of NQM was the quaternary ammonium salt. All water-soluble BQM precursors were further investigated for their ability to alkylate and cross-link plasmid DNA and oligonucleotides by gel electrophoresis: the BQMs were more efficient than the isomeric o-BQM (binol quinone methide analogue of 2,3-naphthoquinone-3- methide). Sequence analysis by gel electrophoresis, HPLC, and MS showed that the alkylation occurred at purines, with a preference for guanine. In particular, a BQM was able to alkylate N7 of guanines resulting in depurination at the oligonucleotide level, and ribose loss at the nucleotide level. The photoreactivity of BQM precursors translated into photocytotoxic and cytotoxic effects on two human cancer cell lines: in particular, one compound showed promising selectivity index on both cell lines.
- Verga, Daniela,Nadai, Matteo,Doria, Filippo,Percivalle, Claudia,Di Antonio, Marco,Palumbo, Manlio,Richter, Sara N.,Freccero, Mauro
-
experimental part
p. 14625 - 14637
(2011/01/04)
-
- Methylation of arenes via Ni-catalyzed aryl C-O/F activation
-
Aryl C-O and C-F can be transformed into C-Me via Ni-catalyzed coupling with MeMgBr under mild conditions. The Royal Society of Chemistry.
- Guan, Bing-Tao,Xiang, Shi-Kai,Wu, Tao,Sun, Zuo-Peng,Wang, Bi-Qin,Zhao, Ke-Qing,Shi, Zhang-Jie
-
p. 1437 - 1439
(2008/12/21)
-
- Electroorganic reactions. Part 56: Anodic oxidation of 2-methyl- and 2-benzylnaphthalenes: Factors influencing competing pathways
-
A systematic investigation of the anodic oxidation in nucleophilic media of 2-methyl and 2-benzylnaphthalenes, substituted at the 6-position in the naphthalene nucleus and at the 4-phenyl position of the benzylic side chain, has been carried out to identify factors favouring side-chain substitution. Cyclic voltammetry confirms that 6-substitution has a profound effect on the oxidation potentials of the naphthalene nucleus and 13C chemical shifts indicate polar effects at the benzylic carbon. However, little side-chain anodic oxidation is observed under any conditions tried; the radical-cations of electron-rich substrates preferentially dimerise and a strongly electron-withdrawing substituent at the 6-position (EtOSO2) promotes nuclear substitution. In contrast, oxidation with DDQ in aqueous acetic acid gives efficient side-chain oxidation for electron rich substrates, consistent with hydride transfer, possibly intramolecularly via a charge transfer complex.
- Utley, James H.P,Rozenberg, Gregor G
-
p. 5251 - 5265
(2007/10/03)
-
- Process of synthesizing binaphthyl derivatives
-
A process of synthesizing a compound of the formula 1: is disclosed, which comprises reacting a compound of the formula 2: with diphenylphosphine in the presence of an amine base and a nickel catalyst to produce a compound of formula 1.
- -
-
-
- Heterocyclic compouds
-
A compound of the general formula wherein: n is 0 or 1; M1 is an amino group; Q is an aromatic heterocyclic group containing a basic nitrogen atom; M2 is an imino group; L is a template group; and A is an acidic group, or an ester or amide derivative thereof, or a sulphonamide group; and pharmaceutically acceptable salts and pro-drugs thereof, for use in the treatment of a disease in which platelet aggregation mediated by the binding of adhesion molecules to GPIIb-IIIa is involved. Novel compounds are also disclosed.
- -
-
-
- Kinetics and mechanism of ammonolysis and alkaline hydrolysis of naphthyl acetates in aqueous medium: Part II - 6-substituted 2-naphthyl acetates
-
Several 6-substituted 2-naphthyl acetates have been prepared and kinetics of their ammonolysis and alkaline hydrolysis studied at 20°, 25° and 30°C at various pH values in water with 1% dioxan at a definite ionic strength. The ammonolysis is first order in [free ammonia] and the process proceeds through a simple unassisted nucleophilic substitution pathway, which includes the zwitterionic tetrahedral intermediate (T±). In no case, is the catalysed pathway visible The reason for the absence of expected-catalysis in the case of ester with methyl substituent is discussed.
- Ananthakrishna Nadar,Rajarathinam
-
p. 342 - 345
(2007/10/03)
-
- Excited-State Proton-Transfer Kinetics: A Theoretical Model
-
The intersecting-state model is applied to excited state proton-transfer reactions.The results are consistent with those previously obtained for the analogous ground-state reactions.The transition-state bond order n* is similar in the ground and excited states: carbon acids have lower n* than nitrogen or oxygen acids.The mixing entropy parameter λ is found to be lower for excited-state than ground-state reactions.The mechanistic implications of this are discussed.
- Arnaut, Luis G.,Formosinho, Sebastiao J.
-
p. 685 - 691
(2007/10/02)
-
- Process for the selective production of dihydroxybenzenes
-
The known nuclear hydroxylation of phenol or substituted phenols or phenol ethers with organic solutions of hydrogen peroxide in the presence of a catalyst is carried out in improved manner by employing both (1) a special, practically water free solution of hydrogen peroxide in an organic solvent which forms an azeotrope with water, which azeotrope boils below the boiling point of hydrogen peroxide, and (2) selenium dioxide as a catalyst. Through this, the nuclear hydroxylation is substantially simpler than previously. Besides, for the first time, it is possible to control the ortho to para ratio or the two ortho ratios to each other.
- -
-
-