*  Enantioselective total synthesis of (-)-zampanolide, a potent microtubule-stabilizing agent. - Semantic Scholar
An enantioselective total synthesis of zampanolide has been accomplished using a novel DDQ/Brønsted acid promoted cyclization as the key reaction. The synthesis features cross-metathesis to construct the trisubstituted olefin and a ring-closing metathesis to form the macrolactone. The final N-acyl aminal formation was stereoselectively accomplished by an organocatalytic reaction.
*  New Trends in Cross-Coupling (RSC Publishing)
Palladium-catalysed cross-coupling reactions constitute a powerful class of chemical methods for the creation of carbon-carbon and carbon-heteroatom bonds used in organic synthesis, famously recognized by the 2010 Nobel Prize awarded to Richard F. Heck, Ei-ichi Negishi and Akira Suzuki 'for palladium-catalysed cross-couplings in organic synthesis.' These methods have become ubiquitous in academic and industrial settings alike, as applications span from industrial production of pharmaceuticals, agrochemicals, polymers, and dyes to the synthesis of complex natural products.New Trends in Cross-Coupling provides the reader with the history and basic, concepts of cross-coupling up to the state of the art in modern coupling reactions from both technology and applied perspectives. A wide breadth of topics including selecting prominent ligand types; advances in Pd-phosphine precatalysts and Pd N-heterocyclic carbene complexes; new reactions such as carboiodination; implementation of new technologies such as
*  Benzylidene compounds
Stilbene Benzylidene compounds are alkene derivatives of benzene . They are primarily divided into two groups: Styrenes (one benzene ) Stilbenes (two benzenes ) Benzylidene is also used to describe a type of protecting group in synthetic organic chemistry of the form PhCH(R) For example, 4,6-O-benzylidene-glucopyranose is a glucose molecule whose 4- and 6-OH groups are protected by being bound to a benzylic carbon, forming a benzyl acetal. See also Dibenzylideneacetone Aurone External links Look up benzylidene in Wiktionary, the free dictionary. Benzylidene Compounds at the US National Library of Medicine Medical Subject Headings (MeSH) Stilbene Benzylidene compounds are alkene derivatives of benzene . They are primarily divided into two groups: Styrenes (one benzene ) Stilbenes (two benzenes ) Benzylidene is also used to describe a type of protecting group in synthetic organic chemistry of the form PhCH(R) For example, 4,6-O-benzylidene-glucopyranose is a glucose molecule whose 4- and 6-OH groups are
*  Sonogashira coupling - Wikipedia
The Sonogashira reaction is a cross-coupling reaction used in organic synthesis to form carbon-carbon bonds. It employs a palladium catalyst to form a carbon-carbon bond between a terminal alkyne and an aryl or vinyl halide. R − ≡ − H + R ′ − X → base, rt Pd cat., Cu cat. R − ≡ − R ′ {\displaystyle {\begin{matrix}{}\\{\ce {R-\!{\equiv }\!-H}}+{\color {Red}{\ce {R'}}}\!-\!{\ce {X->[{\text{Pd cat., Cu cat.}}][{\text{base, rt}}]R-\!{\equiv }\!}}{\color {Red}{\ce {-R'}}}\end{matrix}}} R': Aryl or Vinyl X: I, Br, Cl or OTf The Sonogashira cross-coupling reaction has been employed in a wide variety of areas, due to its usefulness in the formation of carbon-carbon bonds. The reaction can be carried out under mild conditions, such as at room temperature, in aqueous media, and with a mild base, which has allowed for the use of the Sonogashira cross-coupling reaction in the synthesis of complex molecules. Its applications include pharmaceuticals, natural products, organic materials, ...
*  DSpace@MIT: Palladium-catalyzed C-N cross-coupling reactions toward the synthesis of drug-like molecules
The development of methodologies for C-N bond formation reactions is an important scientific challenge because of many academic and industrial applications. This work will focus particularly on palladium-catalyzed cross-couplings of amine-containing compounds with aryl halides. The scope of the BrettPhos precatalyst for the cross-coupling of ortho-substituted aryl iodides with amides is studied using substrates with a variety of functional groups. Due to potential metal-chelating issues with some of the substrates used in this study, a proposed ligand synthesis is discussed in which one of the methoxy groups of BrettPhos is replaced with a morpholine capable of occupying palladium's open coordination site during its catalytic cycle. A final C-N bond formation study focuses on the cross-coupling of aryl halides with amidine salts. For this cross-coupling, a methodology has been developed that can be applied to various electron-rich, electron-poor, and electron-neutral substrates. Furthermore, the ...
*  British Library EThOS: Studies of ruthenium and osmium carbonyl clusters with unsaturated cyclic hydrocarbons
Chapter one contains a brief summary of the cluster-surface analogy, with a structural comparison between metal clusters and the chemisorbed state. Particular emphasis is directed towards the adsorption sites adopted by benzene on the metal surface, and the analogous coordination modes found in cluster compounds. Chapter two describes the synthesis and characterisation of a number of benzene and cyclic C6 alkene containing clusters based on an osmium tetrahedral framework, in which the chemistry is dominated by C-H bond activation reactions. Chapter three deals with the analogous ruthenium chemistry, in which a butterfly arrangement of the four metal atoms seems to predominate. An example of cluster mediated ring contraction and its relevance to surface chemistry is discussed, as is the synthesis of an octaruthenium benzene cluster. The molecular organization of arene cluster complexes in the solid-state is also presented. Chapter four introduces the [2.2]paracyclophane molecule as a new class ...
*  3240-34-4 - Iodosobenzene diacetate, 98+% - (Diacetoxyiodo)benzene - DIB - B24531 - Alfa Aesar
Similarly, in the presence of an orthoformate and sulfuric acid, flavanones undergo a 1,2-aryl shift to give 2-aryl-2,3-dihydrobenzofuran-3-carboxylates: Bull. Chem. Soc. Jpn., 68, 1168 (1995). However, iodosobenzene diacetate alone oxidizes flavanones to flavones: J. Chem. Res. (Synop.), 213 (1995). For a review of the use of the reagent in heterocyclic synthesis, see: Synlett, 221 (1994). Useful reagent for mild, rapid cleavage of 1,3-dithianes to the parent carbonyl compounds: Syn. Commun., 30, 4081 (2000). In combination with iodine, forms the acyl hypoiodite, which adds to alkenes: Bull. Chem. Soc. Jpn., 41, 1476 (1968), iodinates alkylbenzenes: J. Am. Chem. Soc., 90, 6187 (1968), and effects the decarboxylative iodination of aromatic carboxylic acids: Synth. Commun., 18, 1327 (1988). See cis,cis-1,5-Cyclooctadiene, B21196, for an intramolecular cyclization reaction. For use in the Pd(II)-catalyzed functionalization of sp2 and sp3 C-H bonds, see: J. Am. Chem. Soc., 126, 2300 ...
*  China (S) - (-) -Propylene Oxide CAS No. 16088-62-3 - China (S)-(-)-Propylene Oxide, 16088-62-3
China (S) - (-) -Propylene Oxide CAS No. 16088-62-3, Find details about China (S)-(-)-Propylene Oxide, 16088-62-3 from (S) - (-) -Propylene Oxide CAS No. 16088-62-3 - Shanghai Sunwise Chemical Co., Ltd.
*  Bifunctional-Thiourea-Catalyzed Diastereo- and Enantioselective Aza-Henry Reaction - Xu - 2005 - Chemistry - A European Journal...
Bifunctional thiourea 1 a catalyzes aza-Henry reaction of nitroalkanes with N-Boc-imines to give syn-β-nitroamines with good to high diastereo- and enantioselectivity. Apart from the catalyst, the reaction requires no additional reagents such as a Lewis acid or a Lewis base. The N-protecting groups of the imines have a determining effect on the chirality of the products, that is, the reaction of N-Boc-imines gives R adducts as major products, whereas the same reaction of N-phosphonoylimines furnishes the corresponding S adducts. Various types of nitroalkanes bearing aryl, alcohol, ether, and ester groups can be used as nucleophiles, providing access to a wide range of useful chiral building blocks in good yield and high enantiomeric excess. Synthetic versatility of the addition products is demonstrated by the transformation to chiral piperidine derivatives such as CP-99,994. ...
*  1-(3-(methyl thio)-butyryl)-2,6,6-trimethyl cyclohexene supplier distributor- CAS 68697-67-6
1-(3-(methyl thio)-butyryl)-2,6,6-trimethyl cyclohexene, 1-(3-(methyl thio)-butyryl)-2,6,6-trimethyl cyclohexene supplier, 1-(3-(methyl thio)-butyryl)-2,6,6-trimethyl cyclohexene distributor, CAS 68697-67-6, 1-(3-(methyl thio)-butyryl)-2,6,6-trimethyl cyclohexene manufacturer, 1-(3-(methyl thio)-butyryl)-2,6,6-trimethyl cyclohexene wholesale
*  Combined quantum chemical and MM-approach to the endo/exo selectivity of Diels-Alder reactions in polar media
The endolexo selectivity of Diels-alder reactions in water and methanol is studied with semiempirical methods using the SCRF approach and a combined quantum chemical (transition state) and molecular mechanics (solvent molecules) method (QC/MM) to determine the effect of protic solvents on the transition slate energies. Evidently, the number of hydrogen bonds that causes strong Coulomb interaction, discriminates heals of formation of transition stales. The results indicate that the s-cis/s-trans conformation of acrylates controls the endolexo selectivity. Copyright (C) 1996 Elsevier Science Ltd ...
*  Asymmetric Addition of Alkylzinc Reagents to Cyclic α,β-Unsaturated Ketones and a Tandem Enantioselective Addition...
Abstract. An asymmetric 1,2-addition of alkyl groups to conjugated cyclic enones gave allylic alcohols with chiral quaternary centers. The resultant allylic alcohols are converted into epoxy alcohols with excellent diastereoselectivities. A semipinacol rearrangement provided α,α-dialkyl-β-hydroxy ketones with all-carbon chiral quaternary centers.. ...
*  Efficient synthesis of chiral cyclic acetals by metal and Brønsted acid co-catalyzed enantioselective four-component cascade...
Four-component Mannich reactions subsequently followed by an intramolecular oxo-Michael addition were developed to efficiently produce chiral cyclic acetals with high diastereoselectivity and enantioselectivity.
*  Lewis Base Activation of Lewis Acids: Catalytic Enantioselective Allylation and Propargylation of Aldehydes
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*  2012 | Grupo de Química Organometálica
Insertion of Allenes into the Pd-C Bond of Ortho-Palladated Primary Arylamines of Biological Relevance: Phenethylamine, Phentermine, (L)-Phenylalanine Methyl Ester, and (L)-Tryptophan Methyl Ester. Synthesis of Tetrahydro-3-benzazepines and Their Salts. García-López, J. A.; Saura-Llamas, I.; McGrady, J. E.; Bautista, D.; Vicente, J. Organometallics 2012, 31, 8333.. http://dx.doi.org/10.1021/om300928j. From Chelate C,N-Cyclopalladated Oximes to C,N,N '-, C,N,S-, or C,N,C '-Pincer Palladium(II) Complexes by Formation of Oxime Ether Ligands. Abellán-López, A.; Chicote, M. T.; Bautista, D.; Vicente, J. Organometallics 2012, 31, 7434.. http://dx.doi.org/10.1021/om3007213. The First Complexes with Two Metallacycles Fused Around a Common Aryl Substituent: "Akimbo" Complexes. Chicote, M. T.; Vicente-Hernández, I.; Jones, P. G.; Vicente, J. Organometallics 2012, 31, 6252.. http://dx.doi.org/10.1021/om300545k. Reactivity toward CO of Eight-Membered Palladacycles Derived from the Insertion of Alkenes ...
7. The method for removing a metallic compound catalyst residue from a polymer solution according to claim 6, wherein the cyclic olefin polymer comprises a norbornene monomer represented by Formula 2: ##STR00008## wherein m is an integer in the range of 0 to 4,R1, R2, R3, and R4 are hydrogen; halogen; linear or branched alkyl that has 1 to 20 carbon atoms and is substituted or unsubstituted with one or more substituent groups selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, haloalkyl, haloalkenyl, haloalkynyl, aryl, haloaryl, aralkyl, haloaralkyl, alkoxy, haloalkoxy, carbonyloxy, halocarbonyloxy, aryloxy, haloaryloxy, silyl, and siloxy; linear or branched alkenyl that has 2 to 20 carbon atoms and is substituted or unsubstituted with one or more substituent groups selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, haloalkyl, haloalkenyl, haloalkynyl, aryl, haloaryl, aralkyl, haloaralkyl, alkoxy, haloalkoxy, carbonyloxy, halocarbonyloxy, aryloxy, ...
*  Protectin D1 - Wikipedia
Protectin D1 also known as neuroprotectin D1 (when it acts in the nervous system) and abbreviated most commonly as PD1 or NPD1 is a member of the class of specialized proresolving mediators. Like other members of this class of polyunsaturated fatty acid metabolites, it possesses strong anti-inflammatory, anti-apoptotic and neuroprotective activity. PD1 is an aliphatic acyclic alkene 22 carbons in length with two hydroxyl groups at the 10 and 17 carbon positions and one carboxylic acid group at the one carbon position. Specifically, PD1 is an endogenous stereoselective lipid mediator classified as an autocoid protectin. Autacoids are enzymatically derived chemical mediators with distinct biological activities and molecular structures. Protectins are signaling molecules that are produced enzymatically from unsaturated fatty acids. Their molecular structure is characterized by the presence of a conjugated system of double bonds. PD1, like other protectins, is produced by the oxygenation of the ω-3 ...
*  Reviews and Book Chapters
Review Articles (peer-reviewed). 10. Synlett 2013, 24, 2335-2339. E I Balmond, M C Galan,* E M McGarrigle* - 'Recent Developments in the Application of Organocatalysis to Glycosylations'. DOI: 10.1055/s-0033-1338970 [Invited contribution to special issue for 5th EuCheMS Organic Division Young Investigators Workshop]. 9. Chem Rev 2007, 107, 5841-5883. E M McGarrigle, E L Myers, O Illa, M A Shaw, S L Riches, V K Aggarwal* - 'Chalcogenides as Organocatalysts.' DOI: 10.1021/cr068402y [Invited contribution to special issue on Organocatalysis] [This article is "highly cited" - in the top 1% of articles published in 2007 by citation count. Source: ISI Web of Science (Thomson Reuters)]. 8. Chem Rev 2005, 105, 1563-1602. E M McGarrigle, D G Gilheany* - 'Chromium- and Manganese-Salen Promoted Epoxidation of Alkenes.' DOI: 10.1021/cr0306945 [This article is "highly cited" - in the top 1% of articles published in 2005 by citation count. Source: ISI Web of Science (Thomson Reuters)]. Chapters in Edited ...
*  Indian Journal of Chemistry
Bejoy Thomas & S Sugunan*. Rare earth exchanged NaFAU-Y zeolites have been prepared by simple ion-exchange methods under moderate conditions. We have investigated the effect of rare earth cations in the textural and structural properties of modified NaFAU-Y zeolite. 23Na and 29Si MASNMR have been used to study the migration tendencies of the rare earth cations from the super cages to the small cages in the zeolite structure, which ultimately reduces the concentration of accessible Br nsted acid sites. 27Al and 29Si MASNMR techniques have been used to study the strain in the Si-O-T and Al-O-T framework tetrahedra induced by the bulky rare earth counter cations in the extra-framework cation positions. The prepared systems have been effectively employed for the alkylation of benzene with 1-octene in the vapour phase. We have tried to correlate the results from various MAS-NMR experiments with the activity of various rare earth exchanged zeolites for the alkylation of benzene with 1-octene. From the ...
*  Michael reaction of functionalized chiral cyclanone imines. Enantioselective synthesis of C2-symmetric cis-(1R,6R)-1,6...
Enantioselective Michael reaction of methyl acrylate or methyl vinyl ketone with a chiral imine of 2-methylcyclohexanone having a protected carbonyl function in the 4-position led to monoprotected keto ester or dione . The latter was converted into the title compound .
*  Items where Subject is "T Technology | TP Chemical technology" - Eprints UPN "Veteran" Yogyakarta
MAHRENI, MAHRENI (2015) ZAT WARNA ALAMI (REVIEW). JURNAL RISET DAERAH, XIV (3). pp. 2307-2324. ISSN - Mahardika Ariyanto, Ibnu (2015) PRA RANCANGAN PABRIK KIMIA KAPROLAKTAM DARI HEXAHYDROBENZOIC ACID DAN NITROSYL SULFURIC ACID KAPASITAS PRODUKSI 40.000 TON/TAHUN. Other thesis, UPN "Veteran" Yogyakarta. Mahardika Sukmana, Prima and Panji Widadi, Fajar (2014) PRA RANCANGAN PABRIK KIMIA ETIL ALKOHOL DARI ETILENA DAN AIR KAPASITAS 100.000 TON/TAHUN. Other thesis, UPN ''VETERAN'' YOGYAKARTA. Mahreni, Mahreni and Abu Bakar, Muhammad and Wan Ramli, Wan Daud and Abdul Amir, Hasan Khadum (2006) PERFORMANCE IMPROVEMENT OF PROTON EXCHANGE MEMBRANE FUEL CELL USING SOL-GEL CASTING TECHNIQUE. In: Seminar Nasional Kejuangan Teknik Kimia 2006, 07 Februari, Yogyakarta. Mahreni, Mahreni and Danang Jaya, Danag and Guntoro, Guntoro and Anggara Setya Wibawa, Wibawa (2017) COAL DESUFURIZATION USING ALKYL ALGINATE (SURFACTANT). In: SEMINAR NASIONAL TAHUN KE-2 CALL FOR PAPERS DAN PAMERAN HASIL PENELITIAN & PENGABDIAN ...
*  Ruthenium-catalyzed insertion of adjacent diol carbon atoms into C-C bonds: Entry to type II polyketides | Science
A variety of catalysts can cleave the strained bonds in four-membered carbon rings and then link the ends to a reactive partner. Bender et al. found that after prying the ring open, a double-duty ruthenium catalyst could forge bonds to a traditionally unreactive partner. They used the reaction to couple cyclobutenones to adjacent saturated carbon centers in diols. This approach efficiently yielded a motif common in polyketide natural products. The reaction proceeds through dehydrogenation and is also amenable to coupling the opened rings to ketol or dione reagents.. Science, this issue p. 779 ...
*  Palladium, 5% on calcium carbonate powder, reduced - 11723 - Alfa Aesar
Palladium (5%) on calcium carbonate powder (reduced) is a heterogeneous and a mild catalyst, used in the hydrogenation of aromatic and aliphatic nitro groups, reductive alkylation/amination, hydrogenation of aromatic carbonyls, olefins, and nitriles. It has high selectivity towards certain chemical reactants, and is often the preferred heterogeneous catalyst for a wide variety of chemical reactions. Partially deactivated form of palladiuim (5%) on calcium carbonate is known as Lindlar catalyst, which is useful for chemo and stereoselective hydrogenations, such as alkynes to cis-alkenes (for e.g., Vitamin synthesis).. ...
0055] Examples of the alkenyl group include C2-10 alkenyl groups such as an ethenyl group, a 1-propenyl group, a 2-propenyl group, a 1-methyl-1-ethenyl group, a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a 2-methyl-1-propenyl group, a 2-methyl-2-propenyl group, a 1-ethyl ethenyl group, a 1-methyl-1-propenyl group, a 1-methyl-2-propenyl group, a 1-pentenyl group, a 2-pentenyl group, a 3-pentenyl group, a 4-pentenyl group, a 1-n-propyl ethenyl group, a 1-methyl-1-butenyl group, a 1-methyl-2-butenyl group, a 1-methyl-3-butenyl group, a 2-ethyl-2-propenyl group, a 2-methyl-1-butenyl group, a 2-methyl-2-butenyl group, a 2-methyl-3-butenyl group, a 3-methyl-1-butenyl group, a 3-methyl-2-butenyl group, a 3-methyl-3-butenyl group, a 1,1-dimethyl-2-propenyl group, a 1-isopropyl ethenyl group, a 1,2-dimethyl-1-propenyl group, a 1,2-dimethyl-2-propenyl group, a 1-cyclopentenyl group, a 2-cyclopentenyl group, a 3-cyclopentenyl group, a 1-hexenyl group, a 2-hexenyl group, a 3-hexenyl group, a ...
0018]In a case where the palladium is supported on one of the carriers other than the titanosilicate, an amount of the palladium to be supported is generally in a range from 0.01% to 20% by weight with respect to the catalyst, and preferably in a range from 0.1% to 5% by weight. In a case where the palladium is supported on the titanosilicate, the above amount is generally in a range from 0.001% to 5% by weight, and preferably in a range from 0.01% to 0.5% by weight. The palladium catalyst supported on the carrier may include one or more kinds of noble metals other than the palladium. Examples of the noble metal other than the palladium encompass platinum, ruthenium, rhodium, iridium, osmium, and gold. An amount of the noble metal other than the palladium to be included is not particularly limited. It is preferable to keep the amount of the palladium in the reactor at a certain level or higher so that catalytic performance of the catalyst is maintained. For example, in a case where the palladium ...