Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L.) and complexation with β-cyclodextrin

• Daniel I. Hădărugă,
• Mustafa Ünlüsayin,
• Alexandra T. Gruia,
• Cristina Birău (Mitroi),
• Gerlinde Rusu and
• Nicoleta G. Hădărugă

Beilstein J. Org. Chem. 2016, 12, 179–191, doi:10.3762/bjoc.12.20

• meaty fish parts were used for oil extraction. GC-grade hexane (Sigma-Aldrich) was the main solvent used for raw and degraded fish oil dilutions. The Supelco 37 Component FAME mix (Sigma-Aldrich) and C8–C20 alkane standard solution (Fluka Chemie AG) were the main tools for identifying the FAMEs in

• NIST/EPA/NIH Mass Spectral Library 2.0 (2002), by using the FAMEs 37 standard mixture analyzed under the same conditions and by comparing the Kovats indices (obtained with the C8–C20 alkane standard) for the known FAMEs for this GC column type. The acquisition and handling of the GC–MS data was

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

• Shintaro Kawano,
• Toshiyuki Kida,
• Mitsuru Akashi,
• Hirofumi Sato,
• Motohiro Shizuma and
• Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

• using an n-alkane/water system [12]. They reported that the most stable emulsion is formed by β-CD–oil complexes when the contact angles are close to 90° at the oil–water interface. Davarpanah et al. examined the relationship between the stability of O/W Pickering emulsions formed through complexation

Recent advances in copper-catalyzed C–H bond amidation

• Jie-Ping Wan and
• Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

• ). While most known literature methods in the copper-catalyzed alkane amidation focused on the transformation of either benzylic, allylic C–H bonds or C–H bonds adjacent to nitrogen or oxygen atoms, the amidation of unactivated C–H bonds in simple linear or cyclic alkanes remained as a challenge. Recently

• bond was not favored. More notably, the exploration on the reaction mechanism disclosed that the activation of the alkyl C–H bond was initiated by the tert-butoxy radical (Scheme 6). Inspired by the alkane C–H activation, Yu and Cheng et al. [51] discovered that directly heating amides in cyclohexane

• the reaction in the synthesis of indoles was later achieved by mean of ligand-free condition via the co-catalysis of Cu(eh)2 (copper(II) 2-ethylhexanoate) and TEMPO under oxygen atmosphere [68]. C(sp)–H bond amidation The C(sp)–H bond in terminal alkynes is more acidic than equivalent alkane and

C–H bond halogenation catalyzed or mediated by copper: an overview

• Wenyan Hao and
• Yunyun Liu

Beilstein J. Org. Chem. 2015, 11, 2132–2144, doi:10.3762/bjoc.11.230

• convert smoothly (Scheme 24). Besides catalyzing the halogenation of inactive alkane substrates via a typical C–H activation, copper catalysis also exhibited important application in the electrophilic halogenation of some active methylene substrates such as ketones or esters. Although these active

Preparative semiconductor photoredox catalysis: An emerging theme in organic synthesis

• David W. Manley and
• John C. Walton

Beilstein J. Org. Chem. 2015, 11, 1570–1582, doi:10.3762/bjoc.11.173

• product (toluene, 38). Diphenylacetic acid yielded tetraphenylethane in a near-quantitative yield but in contrast, the related 9H-fluorene-9-carboxylic acid produced the reduced alkane (9H-fluorene) as the major product. Incorporation of substituents on the phenyl ring proved a success; arylacetic acids

One-pot odourless synthesis of thioesters via in situ generation of thiobenzoic acids using benzoic anhydrides and thiourea

• Mohammad Abbasi and
• Reza Khalifeh

Beilstein J. Org. Chem. 2015, 11, 1265–1273, doi:10.3762/bjoc.11.141

• preparation of alkane thiols using thiourea and alkyl halides is a well-known reaction in organic synthesis. In addition, two methods for the synthesis of thioacids from acyl chlorides using N,N-dimethylthioformamide [51] or thioacetamide [52] have been reported. As far as we know, a similar reaction using

The chemical behavior of terminally tert-butylated polyolefins

• Dagmar Klein,
• Henning Hopf,
• Peter G. Jones,
• Ina Dix and
• Ralf Hänel

Beilstein J. Org. Chem. 2015, 11, 1246–1258, doi:10.3762/bjoc.11.139

• amounts of 9 and 10 grew at the cost of 8, and when the hydrogenation was run for two days, alkane 10 was the only reduction product. It seems safe to assume that we are dealing with a stepwise process, with 8 and 9 serving as intermediates en route to 10. Comparing the two experiments starting from 3 and

Hybrid macrocycle formation and spiro annulation on cis-syn-cis-tricyclo[6.3.0.0^2,6]undeca-3,11-dione and its congeners via ring-closing metathesis

• Sambasivarao Kotha,
• Ajay Kumar Chinnam and
• Rashid Ali

Beilstein J. Org. Chem. 2015, 11, 1123–1128, doi:10.3762/bjoc.11.126

• derivative 7 (Figure 3). The key steps involved here are: double Fischer indolization and RCM. To install the alkane chain connecting the two nitrogen atoms, we plan to use alkylation with allylbromide followed by RCM and hydrogenation protocols. It is known that a mono-indole derivative was obtained via

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

• radical mechanisms were proposed, the common feature is the generation of alkene via the radical dehydrogenation of alkane. 2.6 Other oxidative systems Esters were synthesized from aldehydes and methanol (6 equiv excess relative to aldehyde) using pyridinium dichromate in DMF [170]. Methyl esters were

The Shono-type electroorganic oxidation of unfunctionalised amides. Carbon–carbon bond formation via electrogenerated N-acyliminium ions

• Alan M. Jones and
• Craig E. Banks

Beilstein J. Org. Chem. 2014, 10, 3056–3072, doi:10.3762/bjoc.10.323

• in situ. The tagged and now stable “reactive intermediate” can then be removed from the electrolyte solution. Warming the tagged “reactive intermediate” converts the micelle (eicosane, a thermosensitive alkane) from solid to liquid and releases the thiomaleimide tagged N-acyliminium ion. Further

Thermal and oxidative stability of the Ocimum basilicum L. essential oil/β-cyclodextrin supramolecular system

• Daniel I. Hădărugă,
• Nicoleta G. Hădărugă,
• Corina I. Costescu,
• Ioan David and
• Alexandra T. Gruia

Beilstein J. Org. Chem. 2014, 10, 2809–2820, doi:10.3762/bjoc.10.298

• solvent for the raw and degraded O. basilicum L. essential oil. Anhydrous calcium chloride (pro analysis) was purchased from Chimopar, Bucharest. The Kovats indices of the O. basilicum L. essential oil compounds and their degradation derivatives were obtained by using a C8–C20 alkane standard solution

• the KI versus tR graph obtained for the C8–C20 alkane standard mixture analyzed under the same conditions by GC–MS. Statistical analysis The β-CD encapsulation-competition data and the main descriptor indicating the hydrophobicity of the compounds (log P – the logarithm of 1-octanol/water partition

Electrocarboxylation: towards sustainable and efficient synthesis of valuable carboxylic acids

• Roman Matthessen,
• Jan Fransaer,
• Koen Binnemans and
• Dirk E. De Vos

Beilstein J. Org. Chem. 2014, 10, 2484–2500, doi:10.3762/bjoc.10.260

• to regenerate the base precursor. Via a radical bromination, followed by a nucleophilic elimination under alkaline conditions, the alkane is oxidized to the alkene base precursor. These alkaline conditions and the four electron withdrawing ethoxy carbonyl groups (R1), prevent further bromination of

Substrate dependent reaction channels of the Wolff–Kishner reduction reaction: A theoretical study

• Shinichi Yamabe,
• Guixiang Zeng,
• Wei Guan and
• Shigeyoshi Sakaki

Beilstein J. Org. Chem. 2014, 10, 259–270, doi:10.3762/bjoc.10.21

• reaction to convert an aldehyde or ketone to an alkane by the use of hydrazine (H2N–NH2) and a base (OH− or alkoxide RO−) [1][2]. The reaction is illustrated in Scheme 1. It is described as a "homogeneous" reaction [3] because the platinum catalyst used initially is not included. The formal change of the W

• lead to a carbanion R1(R2)HC−. Protonation of the carbanion affords the product alkane. It is believed that the hydrazone anion is involved in the rate-determining step of the W-K reaction [9]. W-K reactions of hydrazones in aprotic solvents were investigated. Cram et al. obtained diphenylmethane H2C

• acetophenone yields the anion due to the anion delocalization in the phenyl ring. In relation to 4, the conversion path from the diimine to the alkane varies with the ketone substrate. In contrast, the path form the ketone to the diimine is invariant. Computational details The reacting systems were

The difluoromethylene (CF₂) group in aliphatic chains: Synthesis and conformational preference of palmitic acids and nonadecane containing CF₂ groups

• Yi Wang,
• Ricardo Callejo,
• Alexandra M. Z. Slawin and
• David O’Hagan

Beilstein J. Org. Chem. 2014, 10, 18–25, doi:10.3762/bjoc.10.4

• -tetrafluorohexadecanoic acid (6c). The X-ray structure of 8,8,11,11-tetrafluorononadecane (27). Conformational interconversion of 1,4-di-CF2 motif. Synthesis route to 8,8-difluorohexadecanoic acid (6a). The synthesis of palmitic acid analogues 6b and 6c. Synthesis route to the tetrafluorinated alkane 27. Supporting

Copper-catalyzed aerobic aliphatic C–H oxygenation with hydroperoxides

• Pei Chui Too,
• Ya Lin Tnay and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2013, 9, 1217–1225, doi:10.3762/bjoc.9.138

• could be envisioned that this aerobic C–H bond oxygenation could be combined with the present remote C–H oxygenation with hydroperoxides, presumably resulting in direct formation of 1,4-dioxygenated compounds from nonoxygenated alkanes (Scheme 6). With this hypothesis, alkane 10 bearing a dibenzylic

• direct 1,4-dioxygenation of alkane 10 was demonstrated by using the present method. Further studies will be carried out to develop more robust and efficient catalytic aerobic radical transformations for polyol synthesis from rather simple alkanes. Aliphatic C–H oxidation with amidines and ketimines by

1-n-Butyl-3-methylimidazolium-2-carboxylate: a versatile precatalyst for the ring-opening polymerization of ε-caprolactone and rac-lactide under solvent-free conditions

• Astrid Hoppe,
• Faten Sadaka,
• Claire-Hélène Brachais,
• Gilles Boni,
• Jean-Pierre Couvercelle and
• Laurent Plasseraud

Beilstein J. Org. Chem. 2013, 9, 647–654, doi:10.3762/bjoc.9.73

• concept was extended to the synthesis of aliphatic polycarbonates, involving the transesterification of DMC with linear alkane diols under solvent-free conditions, and based on a two-step polymerization process [50]. The high reactivity of imidazolium-2-carboxylates can be explained by their facile

Amino-substituted diazocines as pincer-type photochromic switches

• Hanno Sell,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2013, 9, 1–7, doi:10.3762/bjoc.9.1

• conformational motion. The first and probably most simple measure to make azobenzene stiffer would be to prevent the phenyl groups from rotating. Connecting both rings with each other via an alkane bridge is probably the most straightforward way to achieve that. Such a molecule, 5,6-dihydrodibenzo[c,g][1,2

Flow photochemistry: Old light through new windows

• Jonathan P. Knowles,
• Luke D. Elliott and
• Kevin I. Booker-Milburn

Beilstein J. Org. Chem. 2012, 8, 2025–2052, doi:10.3762/bjoc.8.229

Evaluation of a chiral cubane-based Schiff base ligand in asymmetric catalysis reactions

• Kyle F. Biegasiewicz,
• Michelle L. Ingalsbe,
• Jeffrey D. St. Denis,
• James L. Gleason,
• Junming Ho,
• Michelle L. Coote,
• G. Paul Savage and
• Ronny Priefer

Beilstein J. Org. Chem. 2012, 8, 1814–1818, doi:10.3762/bjoc.8.207

• and a phenyl group. In fact, the C–H bond of cubane has been shown to have ~31% s-character [20], compared to 25% for a simple alkane and 33% for an aromatic hydrogen. Due to the bulk of the cube it was initially envisioned that there would be high stereocontrol; however, the stereoselectivity was

Metal–ligand multiple bonds as frustrated Lewis pairs for C–H functionalization

• Matthew T. Whited

Beilstein J. Org. Chem. 2012, 8, 1554–1563, doi:10.3762/bjoc.8.177

• a transformation has not been realized with the early metal complexes that are most reactive toward C–H bonds, probably because reductive elimination is strongly disfavored relative to the 1,2-elimination of alkane. Another possibility would be an initial 1,2-addition of a C–H bond across M═E

Regio- and stereoselective oxidation of unactivated C–H bonds with Rhodococcus rhodochrous

• Elaine O’Reilly,
• Suzanne J. Aitken,
• Gideon Grogan,
• Paul P. Kelly,
• Nicholas J. Turner and
• Sabine L. Flitsch

Beilstein J. Org. Chem. 2012, 8, 496–500, doi:10.3762/bjoc.8.56

• hydrocarbons, including n-alkanes and isoalkanes, and has been reported to catalyse the terminal hydroxylation of chloroalkanes and long-chain alkenes [13]. It has been suggested that this strain contains an alkane-inducible NADH-dependent hydroxylase that catalyses the oxidation of n-octane to 1-octanol [13

Biocatalytic hydroxylation of n-butane with in situ cofactor regeneration at low temperature and under normal pressure

• Svenja Staudt,
• Christina A. Müller,
• Jan Marienhagen,
• Christian Böing,
• Stefan Buchholz,
• Ulrich Schwaneberg and
• Harald Gröger

Beilstein J. Org. Chem. 2012, 8, 186–191, doi:10.3762/bjoc.8.20

• nonfunctionalized alkanes represents one of the most challenging types of reactions that organic chemists currently face [1][2][3]. A particular challenge in this field is the functionalization of volatile n-alkanes, which are present as gases under ambient conditions. A short n-alkane molecule that fulfils these

Molecular rearrangements of superelectrophiles

• Douglas A. Klumpp

Beilstein J. Org. Chem. 2011, 7, 346–363, doi:10.3762/bjoc.7.45

• this study, protolysis steps with alkanes often leads to β-scission reactions (cleavage of the alkane-based carbocations). This reaction path is not observed with superelectrophiles 70, 71, or 73, because these types of cleavage reactions would generate dicationic species with the cationic charges in

Light-induced olefin metathesis

• Yuval Vidavsky and
• N. Gabriel Lemcoff

Beilstein J. Org. Chem. 2010, 6, 1106–1119, doi:10.3762/bjoc.6.127

• trioxide (MoO3/SiO2) could be activated by UV irradiation under an alkane atmosphere in the metathesis of propene and 1-hexene. More recently, Sundararajan et al. [52][53][54], and Higashimura et al. [55] applied W(CO)6/CX4/hν methodologies for the polymerisation of alkyne derivatives, especially

Novel tetracyclic structures from the synthesis of thiolactone-isatin hybrids

• Renate Hazel Hans,
• Hong Su and
• Kelly Chibale

Beilstein J. Org. Chem. 2010, 6, No. 78, doi:10.3762/bjoc.6.78

• isatin scaffold, (ii) the flexible alkane tether (n = 3–5) which allows for the proper alignment of the orbitals of the reacting groups and (iii) the rigidity [42] of the isatin and thiolactone ring systems. In the absence of supporting information we speculate that the observed regioselectivity may be