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1.	Aeluri, Madhu, et al. (författare) 14-Membered Macrocyclic Ring-Derived Toolbox : The Identification of Small Molecule Inhibitors of Angiogenesis and Early Embryo Development in Zebrafish Assay 2013 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 15:3, s. 436-439 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract A highly practical and modular synthesis to obtain a diverse 14-membered ring-based macrocyclic toolbox is achieved. These compounds were further tested in zebrafish assays related to early embryonic development, angiogenesis, and neurogenesis, respectively. 1.4c was Identified as an antiangiogenesis agent.
2.	Agrawal, Santosh, et al. (författare) Readily Available Ruthenium Complex for Efficient Dynamic Kinetic Resolution of Aromatic alpha-Hydroxy Ketones 2014 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 16:8, s. 2256-2259 Tidskriftsartikel (refereegranskat)abstract A ruthenium complex formed from commercially available [Ru(p-cymene)Cl-2](2) and 1,4-bis(diphenylphosphino)butane catalyzes the racemization of aromatic alpha-hydroxy ketones very efficiently at room temperature. The racemization is fully compatible with a kinetic resolution catalyzed by a lipase from Pseudomonas stutzeri. This is the first example of dynamic kinetic resolution of alpha-hydroxy ketones at ambient temperature in which the metal and enzyme catalysts work in concert in one pot at room temperature to give quantitative yields of esters of alpha-hydroxy ketones with very high enantioselectivity.
3.	Agrawal, Santosh, et al. (författare) Selective Alkylation of (Hetero)Aromatic Amines with Alcohols Catalyzed by a Ruthenium Pincer Complex 2012 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 14:6, s. 1456-1459 Tidskriftsartikel (refereegranskat)abstract A readily available pincer ruthenium(II) complex catalyzes the selective monoalkylation of (hetero)aromatic amines with a wide range of primary alcohols (including pyridine-, furan-, and thiophene-substituted alcohols) with high efficiency when used in low catalyst loadings (1 mol %). Tertiary amine formation via polyalkylation does not occur, making this ruthenium system an excellent catalyst for the synthesis of sec-amines.
4.	Akkarasamiyo, Sunisa, et al. (författare) Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling Reaction of Naphthyl and Quinolyl Alcohols with Boronic Acids 2019 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 21:12, s. 4782-4787 Tidskriftsartikel (refereegranskat)abstract A nickel-catalyzed C(sp(3))-C(sp(2)) Suzuki cross-coupling of arylboronic acids and (hetero)naphthyl alcohols has been developed. A Ni(dppp) Cl-2 complex showed the highest efficiency and broadest substrate scope. High functional group tolerance has been achieved where 35 compounds could be generated in good to excellent yields, including both primary and secondary benzylic alcohols. Mechanistic studies using multiple NMR techniques as well as ESI-HRMS showed that the C-O cleavage is facilitated by an activation of the benzylic alcohol through formation of a boronic ester intermediate.
5.	Alam, Rauful, et al. (författare) Selective Formation of Adjacent Stereocenters by Allylboration of Ketones under Mild Neutral Conditions 2013 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 15:10, s. 2546-2549 Tidskriftsartikel (refereegranskat)abstract Allylboronic acids readily react with a broad variety of ketones, affording homoallylic alcohols with adjacent quaternary and tertiary stereocenters. The reaction proceeds with very high anti stereoselectivity even if the substituents of the keto group have a similar size. a-Keto acids react with syn stereoselectivity probably due to the formation of acyl boronate intermediates. The allylation reactions proceed without added acids/bases under mild conditions. Because of this, many functionalities are tolerated even with in situ generated allylboronic acids.
6.	Alamsetti, Santosh Kumar, et al. (författare) Palladium-Catalyzed Intramolecular Hydroamination of Propargylic Carbamates and Carbamothioates 2014 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 16:5, s. 1434-1437 Tidskriftsartikel (refereegranskat)abstract An efficient and simple methodology was developed for the synthesis of oxazolidinones, oxazolidinthiones, imidazolidinthiones, and imidazolidinones from the corresponding propargylic starting materials using Pd(OAc)(2) and n-Bu4NOAc as catalysts in DCE at room temperature.
7.	Albers, Michael F, et al. (författare) Amino acid building blocks for efficient Fmoc solid-phase synthesis of peptides adenylylated at serine or threonine 2011 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 13:22, s. 6014-6017 Tidskriftsartikel (refereegranskat)abstract The first straightforward building block based (non-interassembly) synthesis of peptides containing adenylylated serine and threonine residues is described. Key features include final global acidolytic protective group removal as well as full compatibility with standard Fmoc solid-phase peptide synthesis (SPPS). The described Thr-AMP SPPS-building block has been employed in the synthesis of the Thr-adenylylated sequence of human GTPase CDC42 (Ac-SEYVP-T(AMP)-VFDNYGC-NH(2)). Further, we demonstrate proof-of-concept for the synthesis of an Ser-adenylylated peptide (Ac-GSGA-S(AMP)-AGSGC-NH(2)) from the corresponding adenylylated serine building block.
8.	Amorati, Riccardo, et al. (författare) Organochalcogen Substituents in Phenolic Antioxidants 2010 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 12:10, s. 2326-2329 Tidskriftsartikel (refereegranskat)abstract Little is known about the ED/EW character of organochalcogen substituents and their contribution to the O-H bond dissociation enthalpy (BDE) in phenolic compounds. A series of ortho- and para-(S,Se,Te)R-substituted phenols were prepared and investigated by EPR, IR, and computational methods. Substituents lowered the O-H BDE by >3 kcal/mol in the para position, while the ortho-effect was modest due to hydrogen bonding ( approximately 3 kcal/mol) to the O-H group.
9.	Andersson, Hans, et al. (författare) Complete regioselective addition of grignard reagents to pyrazine N-oxides, toward an efficient enantioselective synthesis of substituted piperazines. 2010 Ingår i: Organic letters. - : American Chemical Society (ACS). - 1523-7052 .- 1523-7060. ; 12:2, s. 284-6 Tidskriftsartikel (refereegranskat)abstract A conceptually new one-pot strategy for the synthesis of protected substituted piperazines via the addition of Grignard reagents to pyrazine N-oxides is presented. This strategy is high yielding (33-91% over three steps), step-efficient, and fast. The synthesized N,N-diprotected piperazines are convenient to handle and allow for orthogonal deprotection at either nitrogen for selective transformations. In addition, this is a synthetic route to enantiomerically enriched piperazines by using a combination of phenyl magnesium chloride and (-)-sparteine, which resulted in enantiomeric excesses up to 83%.
10.	Andersson, Hans, et al. (författare) Synthesis of 2-Substituted Pyridines via a Regiospecific Alkylation, Alkynylation, and Arylation of Pyridine N-Oxides 2007 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 9:7, s. 1335-7 Tidskriftsartikel (refereegranskat)abstract Sequential addition of Grignard reagents to pyridine N-oxides in THF at room temperature followed by treatment with acetic anhydride at 120 C afforded 2-substituted pyridines in good to high yields. Furthermore, by exchanging acetic anhydride for DMF in the second step, 2-substituted pyridine N-oxides were obtained, as intermediates suitable for addition of a second Grignard reagent for the synthesis of 2,6-disubstituted pyridines.
11.	Ankner, Tobias, 1976, et al. (författare) KHMDS enhanced SmI(2)-mediated reformatsky type alpha-cyanation. 2010 Ingår i: Organic letters. - : American Chemical Society (ACS). - 1523-7052 .- 1523-7060. ; 12:10, s. 2210-3 Tidskriftsartikel (refereegranskat)abstract A novel combination of SmI(2), KHMDS, and TsCN can be utilized to introduce a cyano group into structurally diverse and highly sensitive 2-alkyl-chroman-4-ones. Subsequent oxidation allows the formed 2-alkyl-3-cyanochromones to be isolated in yields ranging from 49 to 77%. In addition, alpha-bromoketones and esters were found to undergo equally effective alpha-cyanation.
12.	Arkhypchuk, Anna I., et al. (författare) One-Pot Intermolecular Reductive Cross-Coupling of Deactivated Aldehydes to Unsymmetrically 1,2-Disubstituted Alkenes 2018 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 20:17, s. 5086-5089 Tidskriftsartikel (refereegranskat)abstract The phospha-Peterson reaction between a lithiated secondary phosphane, MesP(Li)TMS, and an aldehyde affords Mes-phosphaalkenes which, upon methanol addition and P-oxidation, react with a second carbonyl compound site specifically to produce unsymmetric alkenes. The E/Z selectivity of the one-pot cross coupling is largely determined by the electronic nature of the aryl substituent of the first aldehyde, with electron-donating groups giving rise to increased amounts of Z-alkenes.
13.	Artacho Ruiz, Josep, et al. (författare) Tröger's Base Twisted Amides: Endo Functionalization and Synthesis of an Inverted Crown Ether 2012 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7052 .- 1523-7060. ; 14:18, s. 4706-4709 Tidskriftsartikel (refereegranskat)abstract Taking advantage of the unconventional reactivity of twisted mono- and bis-amides of Tröger's base (TB), rac-6 and rac-7, respectively, the first synthesis of a 6-endo-monosubstituted TB analogue, rac-9, and the first rational synthesis of a 6,12-endo,endo-disubstituted TB analogue, rac-11, have been achieved. The bis-TB crown ether, meso-13, was prepared starting from rac-7. Meso-13 constitutes a rare example of a crown ether with an inverted methylene bridge-to-bridge bis-TB conformation both in solution and in the solid state, resulting in a reluctance to act as a receptor for cations.
14.	Arvela, Riina K, et al. (författare) Suzuki coupling of aryl chlorides with phenylboronic acid in water, using microwave heating with simultaneous cooling 2005 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 7:11, s. 2101-2104 Tidskriftsartikel (refereegranskat)abstract We present here a methodology for the Suzuki coupling of aryl chlorides with phenylboronic acid using Pd/C as a catalyst, water as a solvent, and microwave heating. We show that simultaneous cooling in conjunction with microwave heating prolongs the lifetime of the aryl chloride substrates during the course of the reaction and, as a result, yields of the desired biaryl as well as overall recovery of material can be increased.
15.	Aydin, Juhanes, et al. (författare) Palladium-pincer complex catalyzed C-C coupling of allyl nitriles with tosyl imines via regioselective allylic C-H bond functionalization 2008 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 10:13, s. 2881-2884 Tidskriftsartikel (refereegranskat)abstract A mechanistically new palladium-pincer complex catalyzed allylation of sulfonimines is presented. This reaction involves C-H bond functionalization of allyl nitriles under mild conditions. The reaction proceeds with a high regioselectivity, without allyl rearrangement of the product. Modeling studies indicate that the carbon-carbon bond formation process proceeds via (η1-allyl)palladium pincer complex intermediates.
16.	Aydin, Juhanes, et al. (författare) Pincer Complex-Catalyzed Coupling Reactions via Palladium (IV) Intermediates 2009 Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 11:13, s. 2852-2854 Tidskriftsartikel (refereegranskat)abstract Palladium pincer complexes directly catalyze the redox coupling reactions of functionalized alkenes and iodonium salts. The catalytic process, which is suitable for mild catalytic functionalization of allylic acetates and electron-rich alkenes, probably occurs through Pd(IV) intermediates. Due to the strong metal−ligand interactions, the oxidation of phosphine and amine ligands of the pincer complexes can be avoided in the presented reactions.
17.	Aydin, Juhanes, et al. (författare) Pincer complex-catalyzed redox coupling of alkenes with iodonium salts via presumed palladium(IV) intermediates 2009 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 11:13, s. 2852-2854 Tidskriftsartikel (refereegranskat)abstract Palladium pincer complexes directly catalyze the redox coupling reactions of functionalized alkenes and iodonium salts. The catalytic process, which is suitable for mild catalytic functionalization of allylic acetates and electron-rich alkenes, probably occurs through Pd(IV) intermediates. Due to the strong metal−ligand interactions, the oxidation of phosphine and amine ligands of the pincer complexes can be avoided in the presented reactions.
18.	Aydin, Juhanes, et al. (författare) Stereoselective pincer-complex catalyzed C-H functionalization of benzyl nitriles under mild conditions. An efficient route to β-aminonitriles 2008 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 10:22, s. 5175-5178 Tidskriftsartikel (refereegranskat)
19.	Bacaicoa, Sara, 1995, et al. (författare) Aerobic Oxidative N-Heterocyclic Carbene-Catalyzed Formal 3+3 Cyclization for the Synthesis of Tetrasubstituted Benzene Derivatives 2022 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 24:49, s. 9146-9150 Tidskriftsartikel (refereegranskat)abstract Herein, we present an accessible aerobic N-heterocyclic carbene (NHC)-catalyzed method that efficiently produces tetrasubstituted benzene rings in a single reaction. The method employs atmospheric oxygen (O2) as the terminal oxidant in a reaction that requires two oxidative steps. The aerobic oxidation is achieved by a selection of electron transfer mediators orchestrating a redox cascade, turning a high-energy aerobic oxidation reaction pathway into a favorable process.
20.	Bacaicoa, Sara, 1995, et al. (författare) Redox Active N-Heterocyclic Carbenes in Oxidative NHC Catalysis 2024 Ingår i: ORGANIC LETTERS. - 1523-7060 .- 1523-7052. ; 26:15, s. 3114-3118 Tidskriftsartikel (refereegranskat)abstract An N-heterocyclic carbene (NHC) covalently linked to a quinone introduces a novel avenue for internal oxidations within oxidative NHC catalysis. The deployment of this hybrid NHC class promotes intramolecular electronic flow in the oxidation of the Breslow intermediate to acyl azolium. The use of the redox active NHC as a catalyst is facilitated by employing aerobic regeneration, yielding carboxylic esters with efficiencies of <= 99%, while generating water as the sole byproduct.
21.	Barange, Deepak Kumar, et al. (författare) Regio- and Stereoselective Alkylation of Pyridine-N-oxides : Synthesis of Substituted Piperidines and Pyridines 2016 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 18:24, s. 6228-6231 Tidskriftsartikel (refereegranskat)abstract Regio- and stereoselective addition of alkyl Grignard reagents to pyridine-N-oxides gave C2-alkylated N-hydroxy-1,2,5,6-tetrahydropyridines and trans-2,3-disubstituted N-hydroxy-1,2,5,6-tetrahydropyridines in good to excellent yields. These intermediates were aromatized or alternatively reduced in one-pot methodologies for efficient syntheses of alkylpyridines or piperidines, respectively. These reactions have a broad substrate scope and short reaction times.
22.	Bartoszewicz, Agnieszka, 1983-, et al. (författare) Building molecular complexity via tandem Ru-catalyzed isomerization/C-H activation 2009 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 11:8, s. 1749-1752 Tidskriftsartikel (refereegranskat)abstract A tandem isomerization/C-H activation of allylic alcohols was performed using a catalytic amount of RUCl(2)(PPh(3))(3). A variety of ortho alkylated ketones have been obtained in excellent yields. This tandem process relies on an in situ generation of a carbonyl functional group that directs the ortho C-H bond activation.
23.	Beauseigneur, Alice, et al. (författare) B-Alkylcatecholborane-Mediated Tandem Radical Conjugated Addition-Aldol Cyclization 2009 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 11:16, s. 3778-3781 Tidskriftsartikel (refereegranskat)abstract A one-pot procedure involving radical conjugate addition of B-alkylcatecholboranes to enones followed by intramolecular aldol reaction is reported. Application to the stereoselective synthesis of monocyclic and bicyclic products with up to four contiguous stereogenic centers is presented.
24.	Belda, O., et al. (författare) Recoverable resin-supported pyridylamide ligand for microwave-accelerated molybdenum-catalyzed asymmetric allylic alkylations : Synthesis of baclofen 2003 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 5:13, s. 2275-2278 Tidskriftsartikel (refereegranskat)abstract The syntheses of a series of 4-monosubstituted pyridylamides and a resin-supported pyridylamide are described. The ligands were evaluated in the microwave-accelerated molybdenum-catalyzed asymmetric allylic alkylation. The reaction afforded the product in high yield and with high regio- and enantioselectivity. The heterogeneous ligand could be reused several times with no change in the reaction outcome. The asymmetric allylic alkylation was employed as the key step in the enantioselective synthesis of (R)-baclofen.
25.	Belhomme, Marie-Charlotte, et al. (författare) Formation of C(sp(3))-C(sp(3)) Bonds by Palladium Catalyzed Cross-Coupling of alpha-Diazoketones and Allylboronic Acids 2016 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 18:10, s. 2503-2506 Tidskriftsartikel (refereegranskat)abstract Palladium catalyzed cross-coupling of allylboronic acids with a-diazoketones was studied. The reaction selectively affords the linear allylic product. The reaction proceeds with formation of a new C(sp(3))-C(sp(3)) bond. The reaction was performed without an external oxidant, likely without the Pd-catalyst undergoing redox reactions.
26.	Bengtson, A, et al. (författare) Fast synthesis of aryl triflates with controlled microwave heating 2002 Ingår i: Organic Letters. - Uppsala Univ, Dept Organ Pharmaceut Chem, BMC, SE-75123 Uppsala, Sweden. : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 4:7, s. 1231-1233 Tidskriftsartikel (refereegranskat)abstract [GRAPHICS] Synthesis of aryl triflates from phenols using N-phenyltriflimide requires only 6 min for completion when conducted with controlled microwave heating. The methodology was applied to both solution- and solid-phase conditions. Ten different aryl triflates were synthesized and isolated in good yields. Applications in high-throughput chemistry are suggested.
27.	Bertozzi, Fabio, et al. (författare) Temporary in situ aluminum and zinc tethering in Diels-Alder reactions 2000 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 2:9, s. 1283-1286 Tidskriftsartikel (refereegranskat)abstract (formula presented) Temporary tethering using aluminum or zinc in Diels-Alder reactions made possible the use of otherwise "noncompatible" combinations of dienes and dienophiles, resulting in the one-step formation of substituted cyclohexene 1,2-bis-methanols. Excellent regioselectivity and also significant stereoselectivity were obtained.
28.	Bogár, Krisztián, et al. (författare) Chemoenzymatic Dynamic Kinetic Resolution of Allylic Alcohols : A Highly Enantioselective Route to Acyloin Acetates 2007 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 9:17, s. 3401-3404 Tidskriftsartikel (refereegranskat)abstract Dynamic kinetic resolution (DKR) of a series of sterically hindered allylic alcohols has been conducted with Candida antarctica lipase B (CALB) and ruthenium catalyst 1. The optically pure allylic acetates obtained were subjected to oxidative cleavage to give the corresponding acylated acyloins in high yields without loss of chiral information.
29.	Borhade, Sanjay R., et al. (författare) Synthesis of Novel Aryl and Heteroaryl Acyl Sulfonimidamides via Pd-Catalyzed Carbonylation Using a Nongaseous Precursor 2013 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 15:5, s. 1056-1059 Tidskriftsartikel (refereegranskat)abstract Hitherto unexplored aryl and heteroaryl acyl sulfonimidamides have been prepared through the development of a new Pd-catalyzed carbonylation protocol. This novel methodology, employing sulfonimidamides as nucleophiles and CO gas ex situ released from solid Mo(CO)(6) in a sealed two-chamber system, yields a wide range of carbamate protected acyl sulfonimidamides in good to excellent yields.
30.	Bose, PP, et al. (författare) Decoration of Au and Ag nanoparticles on self-assembling pseudopeptide-based nanofiber by using a short peptide as capping agent for metal nanoparticles 2007 Ingår i: Organic letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 9:13, s. 2489-2492 Tidskriftsartikel (refereegranskat)
31.	Bueno Pérez, Lynette, et al. (författare) Caeruleanone A, a rotenoid with a new arrangement of the D-ring from the fruits of Millettia caerulea. 2014 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 16:5, s. 1462-1465 Tidskriftsartikel (refereegranskat)abstract Caeruleanone A (1), a novel rotenoid with an unprecedented arrangement of the D-ring, was isolated with another two new analogues, caeruleanones B (2) and C (3), together with 11 known rotenoids from the fruits of Millettia caerulea. The structures of the new compounds were determined by spectroscopic data analysis, with that of 1 being confirmed by single-crystal X-ray diffraction. Compounds 2 and 3 displayed potent mitochondrial transmembrane potential inhibitory and quinone reductase induction activities.
32.	Cadu, Alban, 1987-, et al. (författare) One-Pot Synthesis of Keto Thioethers by Palladium/Gold-Catalyzed Click and Pinacol Reactions 2014 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 16:21, s. 5556-5559 Tidskriftsartikel (refereegranskat)abstract An atom-efficient synthesis of keto thioethers was devised via tandem gold/palladium catalysis. The reaction proceeds through a regioselective thiol attack at the β-position of the alcohol, followed by an alkyl, aryl, or benzyl 1,2-shift. Both acyclic and cyclic systems were studied, in the latter case leading to the ring expansion of cyclic substrates.
33.	Cassani, Carlo, 1984, et al. (författare) Photocatalytic decarboxylative reduction of carboxylic acids and its application in asymmetric synthesis 2014 Ingår i: Organic Letters. - : American Chemical Society. - 1523-7060 .- 1523-7052. ; 16:16, s. 4228-4231 Tidskriftsartikel (refereegranskat)abstract The decarboxylative reduction of naturally abundant carboxylic acids such as α-amino acids and α-hydroxy acids has been achieved via visible-light photoredox catalysis. By using an organocatalytic photoredox system, this method offers a mild and rapid entry to a variety of high-value compounds including medicinally relevant scaffolds. Regioselective decarboxylation is achieved when differently substituted dicarboxylic acids are employed. The application of this method to the synthesis of enantioenriched 1-aryl-2,2,2-trifluoroethyl chiral amines starting from natural α-amino acids further testifies to the utility of the developed photocatalytic decarboxylative reduction protocol.
34.	Chen, Yan, et al. (författare) Silver-Promoted (4+1) Annulation of Isocyanoacetates with Alkylpyridinium Salts : Divergent Regioselective Synthesis of 1,2-Disubstituted Indolizines 2021 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 23:19, s. 7555-7560 Tidskriftsartikel (refereegranskat)abstract An unprecedented silver-promoted regioselective (4 + 1) annulation of isocyanoacetates with pyridinium salts is reported. The established protocol provides controlled, facile, and modular access to a range of synthetically useful N-fused heterocyclic scaffolds containing indolizines, pyrrolo[1,2-a]quinolines, pyrrolo[2,1-a]isoquinolines, and 1H-imidazo[4,5-a]indolizin-2(3H)-ones. A mechanistic pathway involving nucleophilic addition/protonation/elimination/cydoisomerization is proposed.
35.	Cheruku, Pradeep, et al. (författare) Asymmetric Hydrogenation of Enol Phosphinates by Iridium Catalysts Having N, P Ligands 2007 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 9:9, s. 1659-1661 Tidskriftsartikel (refereegranskat)abstract Enol phosphinates, which are structural analogues of enol acetates, have for the first time been employed as substrates for Ir-catalyzed asymmetric hydrogenation. A number of enol phosphinates have been synthesized and reduced successfully with up to and above 99% ee.
36.	Chinthakindi, PK, et al. (författare) A Synthesis of "Dual Warhead" β-Aryl Ethenesulfonyl Fluorides and One-Pot Reaction to β-Sultams 2017 Ingår i: Organic letters. - : American Chemical Society (ACS). - 1523-7052 .- 1523-7060. ; 19:3, s. 480-483 Tidskriftsartikel (refereegranskat)
37.	Chowdhury, Rajdip, 1993-, et al. (författare) Modular Synthesis of (Borylmethyl)silanes through Orthogonal Functionalization of a Carbon Atom 2023 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 25:11, s. 1935-1940 Tidskriftsartikel (refereegranskat)abstract (Borylmethyl)trimethylsilanes are important building blocks in organic synthesis displaying a unique reactivity. Yet, the synthesis of more advanced derivatives is limited by the advanced silicon intermediates required for their preparation. Herein, a one-pot synthesis of (borylmethyl)silanes is developed, sourced on available alkyl-, aryl-, alkoxy-, aryloxy-, and silyl-hydrosilane materials. The privileged reactivity of N-hydroxyphthalimidyl diazoacetate (NHPI-DA) in Si–H insertion and α-silyl redox-active esters in different decarboxylative borylation reactions are scrutinized.
38.	Colas, Kilian, et al. (författare) i-Pr2-NMgCl·LiCl Enables the Synthesis of Ketones by Direct Addition of Grignard Reagents to Carboxylate Anions 2019 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 21:19, s. 7908-7913 Tidskriftsartikel (refereegranskat)abstract The direct preparation of ketones from carboxylate anions is greatly limited by the required use of organolithium reagents or activated acyl sources that need to be independently prepared. Herein, a specific magnesium amide additive is used to activate and control the addition of more tolerant Grignard reagents to carboxylate anions. This strategy enables the modular synthesis of ketones from CO2 and the preparation of isotopically labeled pharmaceutical building blocks in a single operation.
39.	Dahlen, A, et al. (författare) SmI2/water/amine mediates cleavage of allyl ether protected alcohols : Application in carbohydrate synthesis and mechanistic considerations 2003 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 5:22, s. 4085-4088 Tidskriftsartikel (refereegranskat)abstract SmI2/H2O/amine provides selective cleavage of unsubstituted allyl ethers in good to excellent yields. This method is therefore useful in deprotection of alcohols and carbohydrates.
40.	Danielsson, Jakob, et al. (författare) Studies Toward Communesin F: A Diels-Alder Approach. 2014 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7052 .- 1523-7060. ; 16:3, s. 784-787 Tidskriftsartikel (refereegranskat)abstract A Diels-Alder reaction is used as a key step in a synthetic study toward communesin F, in order to simultaneously introduce both of the all-carbon quaternary stereocenters with complete control of relative stereochemistry. Further manipulations of the cycloadduct, toward the hexacyclic core-structure of communesin F, are also disclosed.
41.	Das, Arindam, et al. (författare) Copper-Catalyzed Cross-Coupling of Allylboronic Acids with alpha-Diazoketones 2015 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 17:19, s. 4754-4757 Tidskriftsartikel (refereegranskat)abstract Copper-catalyzed cross-coupling of substituted allylboronic acids with alpha-diazoketones was studied. This allylation reaction is highly regioselective, providing the branched allylic product. The process involves creation of a new C(sp(3))-C(sp(3)) bond by retaining the keto functional group of the alpha-diazoketone precursor.
42.	Das, Arindam, et al. (författare) Stereocontrol in Synthesis of Homoallylic Amines. Syn Selective Direct Allylation of Hydrazones with Allylboronic Acids 2014 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 16:14, s. 3808-3811 Tidskriftsartikel (refereegranskat)abstract Allylboronic acids directly react with acyl hydrazones, affording homoallylic amine derivatives. The reaction proceeds with very high syn selectivity, which is the opposite of the stereochemistry observed for allylboration of imines. The reaction can be carried out with both aromatic and aliphatic acyl hydrazones. Based on our studies the excellent syn stereochemistry can be explained by chelation control of the acyl hydrazone and the B(OH)(2) moiety.
43.	Dasari, Bhanudas, et al. (författare) Macrocyclic Glycohybrid Toolbox Identifies Novel Antiangiogenesis Agents from Zebrafish Assay 2013 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 15:3, s. 432-435 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract A practical and modular approach to obtain a diverse set of 14-membered macrocyclic compounds from carbohydrates is developed that utilizes functional groups at C-1 and C-5. The evaluation of this toolbox in various zebrafish assays led to the identification of 2.7f as an antianglogenesis agent.
44.	Davis, Todd A, et al. (författare) Reduction of beta-hydroxyketones by SmI2/H2O/Et3N. 2005 Ingår i: Organic letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 7:1, s. 119-22 Tidskriftsartikel (refereegranskat)abstract Reduction of a series of beta-hydroxyketones by SmI2/H2O/Et3N provided 1,3-diols in quantitative yields. The reactions were exceedingly clean with no byproduct formation, negating the need for further purification. Most reactions provided moderate to excellent diastereoselectivity with syn-diols as the major isomer in most instances.
45.	Dey, Chandan, et al. (författare) Metal-Free C-Arylation of Nitro Compounds with Diaryliodonium Salts 2015 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 17:18, s. 4554-4557 Tidskriftsartikel (refereegranskat)abstract An efficient, mild, and metal-free arylation of nitro-alkanes with diaryliodonium salts has been developed, giving easy access to tertiary nitro compounds. The reaction proceeds in high yields without the need for excess reagents and can be extended to alpha-arylation of nitroesters. Nitroalkanes were selectively C-arylated in the presence of other easily arylated functional groups, such as phenols and aliphatic alcohols.
46.	Du, Yu, et al. (författare) N-Confused Hexapyrrolic Phlorinoid with NIR Absorption : Synthesis, Fusion, Oxidation, and Copper(II) Coordination 2020 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 22:24, s. 9648-9652 Tidskriftsartikel (refereegranskat)abstract An N-confused hexapyrrolic phlorinoid 1 and its isomer N-fused hexapyrrolic phlorinoid 2 were synthesized through [4 + 2] condensation. Both 1 and 2 can be readily transformed into N-confused hexapyrrolic phlorinone 3 under aerobic conditions. Coordination of 1 with Cu(acac)(2) afforded two different mono-Cu(II) complexes 4 and 5 with CNNN and ONNN coordination environments, respectively. The NIR absorption bands can be effectively modulated up to 1265 nm through the oxidation, fusion, and metalation reactions.
47.	Ekebergh, Andreas, 1984, et al. (författare) Oxidative Coupling as a Biomimetic Approach to the Synthesis of Scytonemin 2011 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7052 .- 1523-7060. ; 13:16, s. 4458-4461 Tidskriftsartikel (refereegranskat)abstract The first total synthesis of the dimeric alkaloid pigment scytonemin is described. The key transformations In Its synthesis from 3-indole acetic acid are a Heck carbocyclization and a Suzuki-Miyaura cross-coupling, orchestrated In a stereospecific tandem fashion, followed by a biosynthetically inspired oxidative dimerization. The tandem sequence generates a tetracyclic (E)-3-(arylidene)-3,4-dihydrocyclopenta[b]indol-2(1H)-one that is subsequently dimerized into the unique homodimeric core structure of scytonemin.
48.	Ekebergh, Andreas, 1984, et al. (författare) Total Synthesis of Nostodione A, a Cyanobacterial Metabolite 2012 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 14:24, s. 6274-6277 Tidskriftsartikel (refereegranskat)abstract The first total synthesis of the mitotic spindle poison nostodione A is described. The inherent oxidative sensitivity of indoles is utilized for a late introduction of a second carbonyl to the cyclopent[b]indole-2-one system. The tricyclic system is prepared from indole-3-acetic acid and O-silylated 4-ethynylphenol, using a stereoselective intramolecular reductive Heck cyclization as the key transformation.
49.	Emtenäs, Hans, et al. (författare) Stereoselective Synthesis of Optically Active β-Lactams, Potential Inhibitors of Pilus Assembly in Pathogenic Bacteria 2000 Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 2, s. 2065-2067 Tidskriftsartikel (refereegranskat)
50.	Enquist, P A, et al. (författare) Ultrafast chemistry : Cobalt carbonyl-mediated synthesis of diaryl ketones under microwave irradiation 2003 Ingår i: Organic Letters. - Uppsala Univ, Uppsala Biomed Ctr, Dept Med Chem, SE-76123 Uppsala, Sweden. : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 5:25, s. 4875-4878 Tidskriftsartikel (refereegranskat)abstract [GRAPHICS] By combining the advantages of metal activation, in situ carbon monoxide delivery, and microwave heating, benzophenones were efficiently synthesized in 6-10 s. These ultrafast carbonylation reactions occur under air by flash heating of aryl iodides in the presence of dicobalt octacarbonyl.

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