New bio-nanocomposites based on iron oxides and polysaccharides applied to oxidation and alkylation reactions

• Daily Rodríguez-Padrón,
• Alina M. Balu,
• Antonio A. Romero and
• Rafael Luque

Beilstein J. Org. Chem. 2017, 13, 1982–1993, doi:10.3762/bjoc.13.194

• potential from an environmental point-of-view since it is able to reduce solvent issues in chemical syntheses. The catalytic activity of the obtained nanocatalysts was investigated in both the oxidation of benzyl alcohol to benzaldehyde and in the alkylation of toluene with benzyl chloride. The microwave

• -assisted oxidation of benzyl alcohol reached 45% conversion after 10 min. The conversion of the alkylation of toluene in both microwave-assisted and conventional heating methods was higher than 99% after 3 min and 30 min, respectively. The transformation of benzyl alcohol and toluene into valuable product

• in both the oxidation and alkylation reaction reveals a potential method for the valorization of lignocellulosic biomass. Keywords: alkylation; benzyl alcohol; benzyl chloride; iron oxide; mechanochemistry; microwave-assisted oxidation; polysaccharide; toluene; Introduction Heterogeneous catalysis

Block copolymers from ionic liquids for the preparation of thin carbonaceous shells

• Sadaf Hanif,
• Bernd Oschmann,
• Dmitri Spetter,
• Muhammad Nawaz Tahir,
• Wolfgang Tremel and
• Rudolf Zentel

Beilstein J. Org. Chem. 2017, 13, 1693–1701, doi:10.3762/bjoc.13.163

• the nanoparticle synthesis avoiding the aggregation of nanoparticles, which would lower the surface area and increases the diffusion distances in the final particles for Na or Li ions. For the in situ nanoparticle synthesis TiCl4 was dissolved in benzyl alcohol and the block copolymer was added and

• polymeric ligand was dissolved in 10 mL of DMSO (Sigma-Aldrich) and added to 70 mL of benzyl alcohol (Acros). The content of the flask was heated to 80 °C. The solution was degassed and filled with argon using a Schlenk line. The process was repeated three times. To this argon filled solution 3.2 mL of

• loss up to 200 °C indicates the presence of the solvent (benzyl alcohol) which was used for the preparation of the particles. A mass loss of 20% can be observed. The black curve shows the functionalized particles after pyrolysis. b) IR spectrum of pure TiO2 particles (black) and the functionalized

Total synthesis of elansolids B1 and B2

• Liang-Liang Wang and
• Andreas Kirschning

Beilstein J. Org. Chem. 2017, 13, 1280–1287, doi:10.3762/bjoc.13.124

• , 12.6, 9.7, 7.0, 6.9, 5.2, 5.1; HRMS (ESI) m/z: [M + Na]+ calculated for C35H65BO6Si2Na, 671.4310; found, 671.4312. Reduction of ketone 9 and formation of benzyl alcohol A solution of ketone 9 (466.2 mg, 0.79 mmol, 1.0 equiv) in THF (3 mL) was added to a suspension of LiAlH4 (599.2 mg, 15.79 mmol, 20

• extracted with ethyl acetate. The combined organic extracts were dried over Na2SO4, filtered and concentrated under reduced pressure. The resulting benzyl alcohol (371.7 mg, 0.63 mmol, 80%, d.r. = 3:1) was obtained after flash column chromatography. Separation of diastereomers was achieved by preparative

• , 131.8, 128.7, 128.3, 128.1, 124.7, 124.1, 123.7, 113.8, 86.7, 81.3, 73.9, 73.5, 64.9, 55.8, 55.3, 52.9, 46.6, 45.3, 38.0, 33.4, 31.1, 26.3, 24.2, 22.7, 21.3, −3.4, −3.3; HRMS (ESI) m/z: [M + Na]+ calculated for C39H48O3SiNa, 615.3270; found, 615.3270. Synthesis of phenol 15 To a solution of the benzyl

NMR reaction monitoring in flow synthesis

• M. Victoria Gomez and
• Antonio de la Hoz

Beilstein J. Org. Chem. 2017, 13, 285–300, doi:10.3762/bjoc.13.31

• with a line of <1 Hz in ethanol. As a proof-of-concept, the integrated flow system (microreactor-stripline NMR chip) was tested in the acylation of benzyl alcohol with acetyl chloride (Figure 7) using DIPEA as the base. The kinetics were studied by in situ monitoring and it was found that 70

• experimental setup of the flow system. (a) Microfluidic probe. (b) Microreactor holder. (c) Stripline NMR chip holder. (d) Arrangement of the microfluidic chip in the holder. Reproduced with permission from reference [44]. Copyright 2009 The American Chemical Society. Acetylation of benzyl alcohol. Spectra at

• (a) 9 s and (b) 3 min. Stoichiometry: benzyl alcohol/DIPEA/acetyl chloride 1:1:1.2. Reproduced with permission from reference [44]. Copyright 2009 The American Chemical Society. a) Design of MICCS and b) schematic diagram of MICCS–NMR [45]. CH2Cl2 solutions of oxime ether and triethylborane were

Phosphated cyclodextrins as water-soluble chiral NMR solvating agents for cationic compounds

• Cira Mollings Puentes and
• Thomas J. Wenzel

Beilstein J. Org. Chem. 2017, 13, 43–53, doi:10.3762/bjoc.13.6

• -methylbenzylamine (4), β-methylphenethylamine (5), 1-methyl-3-phenylpiperazine (6), ephedrine (7), α-(methylaminoethyl)benzyl alcohol (8), 2-tert-butylamino-1-phenylethanol (9), α-(1-aminoethyl)-4-hydroxybenzyl alcohol (10), tyrosinol (11), 3-dimethylamino-2-methylpropiophenone (12), cis-(2-benzylamino

Solvent-free, visible-light photocatalytic alcohol oxidations applying an organic photocatalyst

• Martin Obst and
• Burkhard König

Beilstein J. Org. Chem. 2016, 12, 2358–2363, doi:10.3762/bjoc.12.229

• solvent like hydrogen-atom transfer or the formation of byproducts could be excluded. For liquid substrates, some examples for photocatalytic, solvent-free conversions are reported, such as the oxidation of benzyl alcohol to benzaldehyde [4] and the oxidation of benzenes to phenols [5]. Another field of

Palladium-catalyzed ring-opening reactions of cyclopropanated 7-oxabenzonorbornadiene with alcohols

• Katrina Tait,
• Oday Alrifai,
• Rebecca Boutin,
• Jamie Haner and
• William Tam

Beilstein J. Org. Chem. 2016, 12, 2189–2196, doi:10.3762/bjoc.12.209

• investigated, starting with cyclohexanol, which resulted in a moderate yield of 63% after only 1 day (Table 5, entry 8). When benzyl alcohol was used, no reaction occurred (Table 5, entry 9) and similarly when phenol was used, no reaction occurred and 8a was recovered (Table 5, entry 10). Conclusion In

Ionic liquids as transesterification catalysts: applications for the synthesis of linear and cyclic organic carbonates

• Maurizio Selva,
• Alvise Perosa,
• Sandro Guidi and
• Lisa Cattelan

Beilstein J. Org. Chem. 2016, 12, 1911–1924, doi:10.3762/bjoc.12.181

• alcohols such as benzyl alcohol, cyclopentanol and menthol [74]. Figure 5 shows some examples of the carbonates obtained in the study. The desired products were achieved at temperatures between 90 and 220 °C. These results highlight the excellent activity and selectivity of these catalytic systems

TMSBr-mediated solvent- and work-up-free synthesis of α-2-deoxyglycosides from glycals

• Mei-Yuan Hsu,
• Yi-Pei Liu,
• Sarah Lam,
• Su-Ching Lin and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2016, 12, 1758–1764, doi:10.3762/bjoc.12.164

• dithiol acetal side product 9. Inspired by the results obtained in the synthesis of S-2-deoxyglycosides, we explored the use of numerous alcohols as acceptors in order to directly synthesize O-2-deoxyglycosides from glycals. In Table 2 the reaction of glucal 1 and benzyl alcohol (12) under similar

Selectively fluorinated cyclohexane building blocks: Derivatives of carbonylated all-cis-3-phenyl-1,2,4,5-tetrafluorocyclohexane

• Mohammed Salah Ayoup,
• David B. Cordes,
• Alexandra M. Z. Slawin and
• David O'Hagan

Beilstein J. Org. Chem. 2015, 11, 2671–2676, doi:10.3762/bjoc.11.287

• –Smith method [13] as illustrated in Scheme 3. For further elaboration, aldehyde 15 was reduced with NaBH4 in good yield to generate the corresponding benzyl alcohol 19 [14]. Iodination of 19 to generate 20 with HI in chloroform [15] proved superior (95% yield) to the more classical Appel protocol which

Convenient preparation of high molecular weight poly(dimethylsiloxane) using thermally latent NHC-catalysis: a structure-activity correlation

• Stefan Naumann,
• Johannes Klein,
• Dongren Wang and
• Michael R. Buchmeiser

Beilstein J. Org. Chem. 2015, 11, 2261–2266, doi:10.3762/bjoc.11.246

• prepare poly(dimethylsiloxane) (PDMS), using three different imidazolium-based free NHCs in combination with benzyl alcohol or methanol as initiator [24]. There, polymerizations were conducted at 80 °C for 16 h to achieve conversions of about 85% (1.5 < ÐM < 1.7, 0.1% catalyst loading). Notably, it was

• stable at room temperature over long periods of time (observed for up to 2 years) without decomposition, exclusion of humidity provided. Polymerization experiments with D4 were conducted solvent-free at elevated temperature (80 °C, 16 h), both in presence and absence of an initiator (benzyl alcohol, BnOH

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

• anion in 70 picks up a proton from the surface so producing the resonance stabilized hydroxybenzyl radical in 71. The latter is reduced to the benzyl anion by a second e− from the TiO2 and is then protonated by a neighboring surface OH (72). The benzyl alcohol product is released most likely along with

Synthesis of icariin from kaempferol through regioselective methylation and para-Claisen–Cope rearrangement

• Qinggang Mei,
• Chun Wang,
• Zhigang Zhao,
• Weicheng Yuan and
• Guolin Zhang

Beilstein J. Org. Chem. 2015, 11, 1220–1225, doi:10.3762/bjoc.11.135

• [12], antidepressant-like [13] and multidrug resistance reversal [14] activities. Although icariin exerts a variety of important bioactivities, reports concerning its synthesis are very scarce. One Chinese patent reported a 15-step total synthesis of icariin from benzyl alcohol with 0.6% overall yield

Photocatalytic nucleophilic addition of alcohols to styrenes in Markovnikov and anti-Markovnikov orientation

• Martin Weiser,
• Sergej Hermann,
• Alexander Penner and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2015, 11, 568–575, doi:10.3762/bjoc.11.62

• –SH full conversion was achieved within six hours, whereas 40 mol % only reached 70% of conversion at that time. Nucleophilic addition of a variety of alcohols to substrate 1 gave the corresponding products in excellent yields (Table 1). Especially the conversion of 1 with benzyl alcohol was

• significantly slower, since longer irradiations were needed. Only the addition of phenol failed completely. Since isopropanol and tert-butanol as sterically demanding nucleophiles gave the corresponding addition products in good yields, it was assumed that the acidity of benzyl alcohol, and more significantly

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

• suggested that the coupling occurs through oxidation of benzyl alcohol to benzaldehyde. Alcohols (OH-reagents) are taken in a twofold molar excess [96] or are used as solvents [96][97]; the reaction time is 20–40 h at 45–80 °C. The aerobic oxidative coupling of aldehydes or primary alcohols as CH-reagents

• [140]. It was proposed that under the reaction conditions benzyl alcohol 135 is oxidized to carboxylic acid 138, while alkylarene gives iodide 139; the nucleophilic substitution between the carboxylate anion and benzyl iodide affords coupling product 137 [140] (Scheme 27). This mechanism differs from

Synthesis of modified cyclic and acyclic dextrins and comparison of their complexation ability

• Kata Tuza,
• László Jicsinszky,
• Tamás Sohajda,
• István Puskás and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2014, 10, 2836–2843, doi:10.3762/bjoc.10.301

• /7.7 g, respectively (90–95%). 1-O-Benzyl-peracetyl-maltooligomers with slight modification of [15]: Acetobromo-G6, G7 and G8 maltooligomers (3 mmol) were dissolved in benzyl alcohol (BnOH, 120 mmol), freshly prepared dry silver carbonate (6 mmol) was added and the suspensions were stirred in the dark

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• -hydroxybenzoate, benzyl alcohol, 2-phenoxyethanol) [45]. The authors established a clear relationship between the binding constants and the antimicrobial activity of the preservatives on various strains: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and C. albicans. Indeed, highly water-soluble

P(O)R₂-directed Pd-catalyzed C–H functionalization of biaryl derivatives to synthesize chiral phosphorous ligands

• Rong-Bin Hu,
• Hong-Li Wang,
• Hong-Yu Zhang,
• Heng Zhang,
• Yan-Na Ma and
• Shang-dong Yang

Beilstein J. Org. Chem. 2014, 10, 2071–2076, doi:10.3762/bjoc.10.215

• (20 mol %), AgOAc (1.5 mmol), TFE (3.0 mL), 100 °C, 24 h, air atmosphere; bSubstrate (0.3 mmol), PhI(OAc)2 (0.9 mmol), Pd(OAc)2 (10 mol %), TFE (3.0 mL), 100 °C, 24 h, air atmosphere; cSubstrate (0.3 mmol), TBHP (1.2 mmol), benzyl alcohol (0.75 mmol), Pd(TFA)2 (10 mol %), DCE (3.0 mL), 60 °C, air

Facile synthesis of 1-alkoxy-1H-benzo- and 7-azabenzotriazoles from peptide coupling agents, mechanistic studies, and synthetic applications

• Mahesh K. Lakshman,
• Manish K. Singh,
• Mukesh Kumar,
• Raghu Ram Chamala,
• Vijayender R. Yedulla,
• Domenick Wagner,
• Evan Leung,
• Lijia Yang,
• Asha Matin and
• Sadia Ahmad

Beilstein J. Org. Chem. 2014, 10, 1919–1932, doi:10.3762/bjoc.10.200

• shown in Scheme 6. Because the guanidinum forms of HBTU and HATU have lower reactivity than the uronium forms [40] slightly more forcing conditions may be needed to obtain satisfactory reactivity. Consistent with this, compound 2c was obtained in 83% yield from a reaction of benzyl alcohol, HATU, and

Multicomponent reactions in nucleoside chemistry

• Mariola Koszytkowska-Stawińska and
• Włodzimierz Buchowicz

Beilstein J. Org. Chem. 2014, 10, 1706–1732, doi:10.3762/bjoc.10.179

• obtained in the presence of 4 Å molecular sieves. The analysis of the reaction products showed that ytterbium triflate induced partial 1,2-elimination of benzyl alcohol from the ribosyl residue of the starting aldehyde 86, consequently leading to the 1',2'-didehydro-derivative of the target product 87

Concise, stereodivergent and highly stereoselective synthesis of cis- and trans-2-substituted 3-hydroxypiperidines – development of a phosphite-driven cyclodehydration

• Peter H. Huy,
• Julia C. Westphal and
• Ari M. P. Koskinen

Beilstein J. Org. Chem. 2014, 10, 369–383, doi:10.3762/bjoc.10.35

• poorly. Nevertheless, washing of an aqueous solution of the polar lithium salts of 2 (crude 2 in aq. LiOH) with organic solvents of increasing polarity (Et2O→EtOAc) allowed to remove BnOH almost completely (<10% of BnOH referred to 2). Residual benzyl alcohol diminished the yield in the following

Tuning the interactions between electron spins in fullerene-based triad systems

• Maria A. Lebedeva,
• Thomas W. Chamberlain,
• E. Stephen Davies,
• Bradley E. Thomas,
• Martin Schröder and
• Andrei N. Khlobystov

Beilstein J. Org. Chem. 2014, 10, 332–343, doi:10.3762/bjoc.10.31

• -dichlorobenzene (ODCB). To link the C60 and C70 fulleropyrrolidines within asymmetric triads with an oxalate spacer we attempted a similar stepwise approach as reported for compounds 1–3 (Scheme 2). Oxalic acid monobenzyl ester monochloride was prepared by equimolar reaction of oxalyl chloride and benzyl alcohol

• °C, and anhydrous benzyl alcohol (1.4 mL) added dropwise over 15 min. After the addition of the alcohol was completed, the reaction mixture was warmed up to room temperature and stirred for 1.5 h. The resulting mixture was analysed by 1H and 13C NMR spectroscopy and found to be a mixture of the

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• underwent Curtius rearrangement upon heating. The intermediate isocyanate was intercepted by benzyl alcohol to provide secondary Cbz-protected amine 192. Bredereck’s reagent (193) [162] was used to generate enamine 194. The enol-form of the remaining carbonyl moiety was transformed into the corresponding

One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor

• Mark C. Bagley,
• Vincenzo Fusillo,
• Robert L. Jenkins,
• M. Caterina Lubinu and
• Christopher Mason

Beilstein J. Org. Chem. 2013, 9, 1957–1968, doi:10.3762/bjoc.9.232

• benzyl alcohol oxidation [27], the esterification of benzoic acid in a microwave tubular flow reactor [28], a continuous flow recycle microwave reactor for homogeneous and heterogeneous processes [29], a mesoscale flow reactor utilizing Fe3O4 as a microwave absorbing packed reactor bed with internal

The preparation of several 1,2,3,4,5-functionalized cyclopentane derivatives

• André S. Kelch,
• Peter G. Jones,
• Ina Dix and
• Henning Hopf

Beilstein J. Org. Chem. 2013, 9, 1705–1712, doi:10.3762/bjoc.9.195

• original synthesis were never fully published [9]. This missing information will be presented in this publication (see Supporting Information File 1). The Tolbert synthesis of 16 is summarized in Scheme 2. The crucial intermediate 5-[(benzyloxy)methyl]cyclopentadiene (12) was first prepared from benzyl

• alcohol (9) via the chloro ether 10 and cyclopentadienylthallium (11) according to a route developed by Corey and co-workers in their prostaglandin work [10]. Cycloaddition of maleic anhydride (MA) to 12 subsequently afforded the endo-adduct 13, which after esterification provided the diester 14 in