1569-60-4Relevant articles and documents
2,6,10-TRIMETHYL-7-(3-METHYLBUTYL)-DODECANE, A NOVEL SEDIMENTARY BIOLOGICAL MARKER COMPOUND.
Yon, D.A.,Maxwell, J.R.,Ryback, G.
, p. 2143 - 2146 (1982)
A C20 isoprenoid alkane (1) reported to occur in several recent sediments, has been isolated from Rozel Point crude oil and its structure confirmed by synthesis.
Carbon-13 NMR Spectra of Saturated Heterocycles. XI - Tetrahydropyrans (Oxanes)
Eliel, Ernest L.,Manoharan, Muthiah,Pietrusiewicz, K. Michal,Hargrave, Karl D.
, p. 94 - 107 (1983)
The 13C NMR spectra of 62 oxanes (tetrahydropyrans) with and without methyl substituents at various ring positions, some of them bearing in addition (or instead) ethyl, vinyl, ethynyl, carbomethoxy and methylol substituents at C-2, have been recorded, and the 294 resulting chemical shifts have been correlated by multiple linear regression analysis.Axial and equatorial α-, β-, γ-, δ-, gem- and vic-parameters for shifts caused by methyl groups at all ring positions, and similar parameters for Et, -CH=CH2, -CCH, CO2Me and CH2OH groups at C-2, are reported.Standard deviations of the parameters are, in most cases, within 0.3 ppm and the agreement of calculated and experimental shifts is excellent.This is probably the largest parameter set of this type extant. 13C NMR spectra of a number of additional substituted tetrahydropyrans, and of 3,6-dihydro-2H-pyrans and 3,4-dihydro-2H-pyrans, are tabulated and discussed.
Essential oil of aristolochia trilobata: Synthesis, routes of exposure, acute toxicity, binary mixtures and behavioral effects on leaf-cutting ants
De Oliveira, Bruna Maria S.,Melo, Carlisson R.,Alves, Péricles B.,Santos, Abra?o A.,Santos, Ane Caroline C.,Santana, Alisson Da S.,Araújo, Ana Paula A.,Nascimento, Pedro E. S.,Blank, Arie F.,Bacci, Leandro
, (2017)
Plants of the genus Aristolochia have been frequently reported as important medicinal plants. Despite their high bioactive potential, to date, there are no reports of their effects on leaf-cutting ants. Therefore, the present study aimed to evaluate the insecticidal activity of the essential oil of Aristolochia trilobata and its major components on Atta sexdens and Acromyrmex balzani, two species of leaf-cutting ants. The bioassays were performed regarding routes of exposure, acute toxicity, binary mixtures of the major components and behavioral effects. Twenty-five components were identified in the essential oil of A. trilobata using a gas chromatographic system equipped with a mass spectrometer and a flame ionization detector. The components found in higher proportions were sulcatyl acetate, limonene, p-cymene and linalool. The essential oil of A. trilobata and its individual major components were efficient against A. balzani and A. sexdens workers when applied by fumigation. These components showed fast and efficient insecticidal activity on ants. The components acted synergistically and additively on A. balzani and A. sexdens, respectively, and caused a strong repellency/irritability in the ants. Thus, our results demonstrate the great potential of the essential oil of A. trilobata and its major components for the development of new insecticides.
Oxone-KI Induced Lactonization and Etherification of Unsaturated Acids and Alcohols: A Formal Synthesis of Mintlactone
Curini, Massimo,Epifano, Francesco,Marcotullio, M. Carla,Montanari, Francesca
, p. 368 - 370 (2004)
Unsaturated acids and alcohols interact with Oxone and KI in acetonitrile-H2O and undergo iodolactonization and iodoetherification in short times with good yields. The reaction has been used for the formal synthesis of mintlactone starting from isopulegol.
Biocatalytic-Based Synthesis of Optically Pure (C-6)-Functionalized 1-(tert-Butyldimethylsilyloxy) 2-Methyl-(E)-2-heptenes
Liang, Shaowo,Paquette, Leo A.
, p. 445 - 452 (1990)
Controlled lipase hydrolysis of sulcatol chloroacetate at pH 7.2 to 55percent completion gives (R)-(-)-sulcatol of 89percent ee.Alkaline hydrolysis of the unreacted ester provides the (S)-(+) enantiomer efficiently and in an optically pure state.The latter is protected at its hydroxyl group, oxidized at its less sterically hindered terminal methyl group, and trans-formed into useful bifunctional reagents possessing 100percent ee.
Pd-Catalyzed Nazarov-Type Cyclization: Application in the Total Synthesis of β-Diasarone and Other Complex Cyclopentanoids
Singh, Bara,Bankar, Siddheshwar K.,Ramasastry
, p. 1043 - 1048 (2022/02/05)
We describe the palladium-catalyzed Nazarov-type cyclization of easily accessible (hetero)arylallyl acetates to pentannulated (hetero)arenes. This method provides ready access to various types of bi-, tri-, tetra-, and pentacyclic cyclopentanoids under ne
Amino Acid-Functionalized Metal-Organic Frameworks for Asymmetric Base–Metal Catalysis
Newar, Rajashree,Akhtar, Naved,Antil, Neha,Kumar, Ajay,Shukla, Sakshi,Begum, Wahida,Manna, Kuntal
supporting information, p. 10964 - 10970 (2021/03/29)
We report a strategy to develop heterogeneous single-site enantioselective catalysts based on naturally occurring amino acids and earth-abundant metals for eco-friendly asymmetric catalysis. The grafting of amino acids within the pores of a metal-organic framework (MOF), followed by post-synthetic metalation with iron precursor, affords highly active and enantioselective (>99 % ee for 10 examples) catalysts for hydrosilylation and hydroboration of carbonyl compounds. Impressively, the MOF-Fe catalyst displayed high turnover numbers of up to 10 000 and was recycled and reused more than 15 times without diminishing the enantioselectivity. MOF-Fe displayed much higher activity and enantioselectivity than its homogeneous control catalyst, likely due to the formation of robust single-site catalyst in the MOF through site-isolation.
Base-free transfer hydrogenation of aryl-ketones, alkyl-ketones and alkenones catalyzed by an IrIIICp* complex bearing a triazenide ligand functionalized with pyrazole
Medrano-Castillo, Layla J.,Collazo-Flores, Miguel á.,Camarena-Díaz, Juan P.,Correa-Ayala, Erick,Chávez, Daniel,Grotjahn, Douglas B.,Rheingold, Arnold L.,Miranda-Soto, Valentín,Parra-Hake, Miguel
, (2020/03/13)
An IrIIICp* complex (2) bearing a triazenide ligand functionalized with pyrazole was synthesized and fully characterized by spectroscopic methods and the structure confirmed by X-ray diffraction studies. The catalytic activity of 2 and the control complex 3, which lacks of pyrazole in its structure, was evaluated in the reduction of aryl-ketones, alkyl-ketones, α,β-unsaturated and γ,δ-unsaturated ketones. The catalytic system, using either 2 or 3, exhibited good to excellent selectivity when tested with ketones and alkenones at 90 °C in 2-propanol as hydrogen source under base-free conditions. Reactivity of 2 in 2-propanol and NaH gave a neutral metal hydride (4) while in the absence of base gave two major cationic hydrides species (5 and 6).
Benzimidazole fragment containing Mn-complex catalyzed hydrosilylation of ketones and nitriles
Ganguli, Kasturi,Mandal, Adarsha,Sarkar, Bidisha,Kundu, Sabuj
, (2020/08/13)
The synthesis of a new bidentate (NN)–Mn(I) complex is reported and its catalytic activity towards the reduction of ketones and nitriles is studied. On comparing the reactivity of various other Mn(I) complexes supported by benzimidazole ligand, it was observed that the Mn(I) complexes bearing 6-methylpyridine and benzimidazole fragments exhibited the highest catalytic activity towards monohydrosilylation of ketones and dihydrosilylation of nitriles. Using this protocol, a wide range of ketones were selectively reduced to the corresponding silyl ethers. In case of unsaturated ketones, the chemoselective reduction of carbonyl group over olefinic bonds was observed. Additionally, selective dihydrosilylation of several nitriles were also achieved using this complex. Mechanistic investigations with radical scavengers suggested the involvement of radical species during the catalytic reaction. Stoichiometric reaction of the Mn(I) complex with phenylsilane revealed the formation of a new Mn(I) complex.
Chemoselective Electrochemical Hydrogenation of Ketones and Aldehydes with a Well-Defined Base-Metal Catalyst
Fokin, Igor,Siewert, Inke
, p. 14137 - 14143 (2020/10/12)
Hydrogenation reactions are fundamental functional group transformations in chemical synthesis. Here, we introduce an electrochemical method for the hydrogenation of ketones and aldehydes by in situ formation of a Mn-H species. We utilise protons and electric current as surrogate for H2 and a base-metal complex to form selectively the alcohols. The method is chemoselective for the hydrogenation of C=O bonds over C=C bonds. Mechanistic studies revealed initial 3 e? reduction of the catalyst forming the steady state species [Mn2(H?1L)(CO)6]?. Subsequently, we assume protonation, reduction and internal proton shift forming the hydride species. Finally, the transfer of the hydride and a proton to the ketone yields the alcohol and the steady state species is regenerated via reduction. The interplay of two manganese centres and the internal proton relay represent the key features for ketone and aldehyde reduction as the respective mononuclear complex and the complex without the proton relay are barely active.
