Skeletal rearrangement of 6,8-dioxabicyclo[3.2.1]octan-4-ols promoted by thionyl chloride or Appel conditions

• Martyn Jevric,
• Julian Klepp,
• Johannes Puschnig,
• Oscar Lamb,
• Christopher J. Sumby and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2024, 20, 823–829, doi:10.3762/bjoc.20.74

• bond migration. This is a mechanistic difference to the related 1,2-oxygen migration reactions of spiroacetals that involve alkoxy intermediates reported by Suarez and co-workers [33][34]. The presence of oxocarbenium ion 27 is inferred due to the formation of two diastereomers in Karban’s previous

Substitution reactions in the acenaphthene analog of quino[7,8-h]quinoline and an unusual synthesis of the corresponding acenaphthylenes by tele-elimination

• Ekaterina V. Kolupaeva,
• Narek A. Dzhangiryan,
• Alexander F. Pozharskii,
• Oleg P. Demidov and
• Valery A. Ozeryanskii

Beilstein J. Org. Chem. 2024, 20, 243–253, doi:10.3762/bjoc.20.24

• , despite the presence of two pyridine nitrogen atoms, is extremely inert towards nucleophilic and oxidative amination reactions. Although molecule 5 does not explicitly contain deactivating electron-donating substituents such as alkoxy and dialkylamino (except for alkyl groups), the observed inertness may

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• species (ROS), such peroxyl, alkoxy and hydroxyl radicals, or carbon-centered radicals, which subsequently induce DNA strand cleavage. In the type-II mechanism, a triplet-excited photosensitizer reacts with molecular oxygen to give highly reactive singlet oxygen, 1O2, as reactive intermediate, which in

Facile access to pyridinium-based bent aromatic amphiphiles: nonionic surface modification of nanocarbons in water

• Lorenzo Catti,
• Shinji Aoyama and
• Michito Yoshizawa

Beilstein J. Org. Chem. 2024, 20, 32–40, doi:10.3762/bjoc.20.5

• below 0.1 mM (Figures S28 and S32, Supporting Information File 1), which is around 10 times lower than that of AA [12][13]. The increased stability against dilution likely arises from reduced electrostatic repulsion and increased anthracene-based π-stacking interactions due to the absence of o-alkoxy

Recent advancements in iodide/phosphine-mediated photoredox radical reactions

• Tinglan Liu,
• Yu Zhou,
• Junhong Tang and
• Chengming Wang

Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131

• cyclization to release an active alkyl radical intermediate C. Once formed, C added to the aldehyde group via a [4 + 2] annulation, releasing the alkoxy radical intermediate D. The latter then underwent a subsequent 1,2-H atom shift to generate the alkyl radical intermediate E which was further oxidized by

Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• , wherein researchers substituted alkoxy chains to enhance solubility and difluoro groups to lower the highest occupied molecular orbital (HOMO) energy level. Qx-derived polymer acceptors have witnessed significant progress in recent years, driven by a contextual understanding of the major issues hindering

• -withdrawing terminal acceptor units, and careful selection of solvents and annealing processes have also been demonstrated as potential solutions to improve charge transport and refine the device fabrication processes. You et al. found that the position of alkoxy side chains on the pendant benzene rings

• significantly influenced the performance of Qx2 acceptors. Three variants of Qx2, i.e., Qx7 and Qx8 were synthesized with alkoxy side chains located at the meta and para positions of the pendant benzene rings. Qx7 exhibited efficient exciton dissociation, good electron-transporting ability, and a PCE of 5.07

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• presence of TMSOTf. Catalyst-free sulfenylation by N-(sulfenyl)succinimides/phthalimides In 2015, oxysulfenylation of styrene derivatives 9 utilizing 1-(arylthio)pyrrolidine-2,5-diones 1 and alkyl/benzyl alcohols 86 toward β-alkoxy sulfides was developed by Fu et al. (Scheme 65) [95]. In this metal-free

• method, diverse β-alkoxy sulfides were synthesized without the need to any catalyst, or additive. The reaction proceeded through the formation of carbonium ion intermediate I, which underwent electrophilic addition of alcohol to provide product 152. In the meantime, N-(arylthio)succinimide 1 as a

Exploring the role of halogen bonding in iodonium ylides: insights into unexpected reactivity and reaction control

• Carlee A. Montgomery and
• Graham K. Murphy

Beilstein J. Org. Chem. 2023, 19, 1171–1190, doi:10.3762/bjoc.19.86

• conversions (RCCs) of the ortho- or para-alkyl derivatives to be consistent at 37% (62b) and 35% (62a), respectively (Scheme 14) [139]. However, when an ortho-alkoxy substituent (61c) was used, a significantly improved 69% RCC (51% radiochemical yield) was achieved for 62c, despite it being derived from an

• reaction’s outcome. Additional examples of intramolecular secondary interactions also exist in the literature, in which ortho-substituents on iodoarene-derived ylides have been key to tuning reactivity and improving reaction outcomes. Zhdankin et al. first reported on this concept, testing ortho-alkoxy

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

First synthesis of acylated nitrocyclopropanes

• Kento Iwai,
• Rikiya Kamidate,
• Khimiya Wada,
• Haruyasu Asahara and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2023, 19, 892–900, doi:10.3762/bjoc.19.67

• , but a dihydrofuran, so the cyclopropane 1b’ reported in the literature [12][13][19] is presumably incorrect [22]. In the cases of donor–acceptor cyclopropanes possessing an electron-donating group such as an alkoxy or amino group, ring expansion caused by an intramolecular attack of nitro oxygen

Eschenmoser coupling reactions starting from primary thioamides. When do they work and when not?

• Lukáš Marek,
• Jiří Váňa,
• Jan Svoboda and
• Jiří Hanusek

Beilstein J. Org. Chem. 2023, 19, 808–819, doi:10.3762/bjoc.19.61

• reactions involve the imidothioate IV formed via deprotonation from nitrogen (pKaN in Scheme 2). The imidothioate IV can undergo cyclization to give an energetically favorable five-membered thiazoline ring VII which then either eliminates a leaving group Y− (when Y: alkoxy, amino) or a water molecule (when

Construction of hexabenzocoronene-based chiral nanographenes

• Ranran Li,
• Di Wang,
• Shengtao Li and
• Peng An

Beilstein J. Org. Chem. 2023, 19, 736–751, doi:10.3762/bjoc.19.54

• -dicyano-p-benzoquinone (DDQ) and methanesulfonic acid in dichloromethane, the helical structure 7 was obtained in a 72% yield [34]. The possible reason for this incomplete cyclization is the electronic effect of the alkoxy groups. Meanwhile, the methoxy version was also synthesized from precursor 5. The

Synthesis of medium and large phostams, phostones, and phostines

• Jiaxi Xu

Beilstein J. Org. Chem. 2023, 19, 687–699, doi:10.3762/bjoc.19.50

• yields with moderate to good diastereoselectivities via Michael addition and nucleophilic addition–elimination (Scheme 17) [39]. The synthesis is a [5 + 2] annulation fashion. The reactions of 2-phenyl/alkoxy-4H-benzo[d][1,3,2]dioxaphosphinin-4-ones 82 and dialkyl 2-benzylidenemalonates 78 produced

• dialkyl 3-aryl-2-phenyl/alkoxy-3-hydrobenzo[f][1,2]oxaphosphepin-5(4H)-one-4,4-dicarboxylate 2-oxides 84 in good yields with excellent diastereoselectivities accompanied by alkyl 5'-alkoxy-2-phenyl/alkoxy-4-oxo-3'-aryl-2,3'-dihydro-4H-2λ5-spiro[benzo[d][1,3,2]dioxaphosphinine-2,2'-[1,2]oxaphosphole]-4

• ]oxaphosphinine 4-oxide and 1-phenyl-3,4-dihydronaphtho[1,8-cd][1,2]oxaphosphepine 1-oxide from 2-(naphthalen-1-yl)ethyl phenylphosphinate. Synthesis of 2-alkoxy-3,5-dimethylene-1,2-oxaphosphepane 2-oxides from dialkyl 2-bromo-1-methylethylphosphonates and trimethylsilyl but-3-ynyl ether. Synthesis of 14-methyl-2

Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

• Austin Pounder,
• Eric Neufeld,
• Peter Myler and
• William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

• the alkoxy group which can finally reductively eliminate the isochromene product. Based on control reactions, the authors proposed the active catalytic species is cationic, as the use of the cationic precatalyst [Cp*Ru(CH3CN)3]PF6 in THF afforded the isochromene as the major product, suggesting a

Asymmetric synthesis of a stereopentade fragment toward latrunculins

• Benjamin Joyeux,
• Antoine Gamet,
• Nicolas Casaretto and
• Bastien Nay

Beilstein J. Org. Chem. 2023, 19, 428–433, doi:10.3762/bjoc.19.32

• a 1,5-anti induction of the aldol reaction [18][19][20] based on chiral alkoxy partner 9. Furthermore, it could be envisaged to reduce the resulting β-hydroxyketone 7 in a diastereoselective manner to obtain a 1,3-diol. This synthetic strategy could thus bring new stereochemical opportunities to

• -induction of the aldol stereocenter by β-alkoxy ketone 9, leading to an (S)-configuration [18][19][20]. This control is supposed to follow a boat transition state A stabilized by a formyl hydrogen bond [30]. It is known to be dependent on the nature of the β-alkoxy substituent, being particularly favoured

Group 13 exchange and transborylation in catalysis

• Dominic R. Willcox and
• Stephen P. Thomas

Beilstein J. Org. Chem. 2023, 19, 325–348, doi:10.3762/bjoc.19.28

• give an enantioenriched borinic ester 44 and β-pinene 45. The borinic ester 44 underwent B‒O/B‒H transborylation (ΔG‡exp = 22.7 kcal mol−1) with HBpin giving H-B-9-BBN and the alkoxy boronic ester 46. Hydroboration of β-pinene 45 by H-B-9-BBN regenerated the myrtanylborane 43 catalyst. Reaction of

• proposed to occur by hydroboration of the carbonyl compound 53 with BH3, followed by B‒O/B‒H transborylation with HBpin (ΔG‡ = 24.5 kcal mol−1), to give the alkoxy boronic ester 56 (Scheme 13). Nicholson, Thomas and co-workers reported the H-B-9-BBN-catalysed diastereoselective reductive aldol-type

• the aluminium-catalysed reduction of aldehydes and ketones with HBpin, using a NacNac-supported aluminium hydride catalyst (Scheme 23) [104]. Using computational analysis, the reaction was proposed to proceed through reduction of the carbonyl 91 by the aluminium hydride 92, to give an alkoxy aluminium

An accelerated Rauhut–Currier dimerization enabled the synthesis of (±)-incarvilleatone and anticancer studies

• Tharun K. Kotammagari,
• Sweta Misra,
• Sayantan Paul,
• Sunita Kunte,
• Rajesh G. Gonnade,
• Manas K. Santra and
• Asish K. Bhattacharya

Beilstein J. Org. Chem. 2023, 19, 204–211, doi:10.3762/bjoc.19.19

• intermediate A tetrahydrofuran intermediate B with cis-fused ring systems is formed as seen in the existing literature [7]. A proton transfer of enolate moiety B yields another enolate C followed by the β-alkoxy elimination [17] of intermediate C to form intermediate D. The intermediate D on protonation leads

Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry

• Eric Gayon,
• Guillaume Lefèvre,
• Olivier Guerret,
• Adrien Tintar and
• Pablo Chourreu

Beilstein J. Org. Chem. 2023, 19, 158–166, doi:10.3762/bjoc.19.15

• functionality indeed affords the terminal oxidized function of the pheromone molecule (alkoxy acetate in 2 or 3, Scheme 4a and 4b, or formyl group in 1, Scheme 4c). As a representative target, we developed the total synthesis of the codling moth sex pheromone, (8E,10E)-dodecadien-1-ol (4), featuring the

Synthetic study toward tridachiapyrone B

• Morgan Cormier,
• Florian Hernvann and
• Michaël De Paolis

Beilstein J. Org. Chem. 2022, 18, 1741–1748, doi:10.3762/bjoc.18.183

• investigation, it is mostly restricted to substrates bearing a tertiary alkoxy group [34]. Few examples of this intermolecular strategy actually involve substrates containing a quaternary carbon and the formation of a C–C bond [35][36]. Of note was the report of Takemoto and Iwata describing the 1,4-addition of

A study of the DIBAL-promoted selective debenzylation of α-cyclodextrin protected with two different benzyl groups

• Naser-Abdul Yousefi,
• Morten L. Zimmermann and
• Mikael Bols

Beilstein J. Org. Chem. 2022, 18, 1553–1559, doi:10.3762/bjoc.18.165

• by alkoxy aluminate at O6. Conclusion It is clear that the O2,O3-DCB groups in fully DCB-protected 1 are affecting the DIBAL-promoted debenzylation tremendously: When present no reaction is observed and when exchanged with unsubstituted benzyl groups debenzylation occurs following the already known

First series of N-alkylamino peptoid homooligomers: solution phase synthesis and conformational investigation

• Maxime Pypec,
• Laurent Jouffret,
• Claude Taillefumier and
• Olivier Roy

Beilstein J. Org. Chem. 2022, 18, 845–854, doi:10.3762/bjoc.18.85

• -peptoid amides were designed. Among these are the N-aryl [33][34][35], N-hydroxy [36], N-alkoxy [37], and N-(acylhydrazide)glycines (Figure 1A) [38][39]. Recently, while our work was in progress, N-imino and N-(alkylamino)glycines have also been proposed to build up peptoids with trans amide bonds [40

The asymmetric Henry reaction as synthetic tool for the preparation of the drugs linezolid and rivaroxaban

• Martin Vrbický,
• Karel Macek,
• Jaroslav Pochobradský,
• Jan Svoboda,
• Miloš Sedlák and
• Pavel Drabina

Beilstein J. Org. Chem. 2022, 18, 438–445, doi:10.3762/bjoc.18.46

•  2). The bulky (R2 = t-Bu) or chiral (R2 = ʟ-menthyl or (−)-bornyl) alkoxy groups (derived from relatively inexpensive and readily available alcohols) were introduced into the carbamate moiety instead of an ethyl group as in aldehydes 15 and 19. Here, the influence of this structural modification of

Mechanistic studies of the solvolysis of alkanesulfonyl and arenesulfonyl halides

• Malcolm J. D’Souza and
• Dennis N. Kevill

Beilstein J. Org. Chem. 2022, 18, 120–132, doi:10.3762/bjoc.18.13

• anhydrides with the chloride leaving group replaced by the appropriate sulfonate leaving group, concerning sulfamoyl chlorides (ZZ'NSO2Cl) with Z and Z' being alkyl or aryl and concerning the solvolysis of chlorosulfate esters (alkoxy- or aryloxysulfonyl chlorides), with the structures ROSO2Cl or ArOSO2Cl

• acetate ion [11]. Hall [12] extended the studies of the hydrolyses of sulfonyl chlorides to sulfamoyl chlorides (ZZ'NSO2Cl, with Z and Z' each either alkyl or aryl) and to alkoxy (or aryloxy) sulfonyl chlorides ROSO2Cl or ArOSO2Cl, also named as alkyl (or aryl) chlorosulfates. These two classes of

• only solvent-ionizing power. Shallow maxima observed when selectivity values (S, indicating the extent of product formation involving replacement of the chloride by the alkoxy group from an alcohol molecule reactive to replacement by the hydroxy group of a water molecule) could be due to two reaction

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

• results, the authors proposed a catalytic cycle (Scheme 12). First, the hydroperoxide, in the presence of an Fe(II) species, generates an Fe(III) intermediate and the alkoxy radical which can oxidize the incoming alcohol 67 to an aldehyde 70. Another equivalent of hydroxy radical, either generated under

The ethoxycarbonyl group as both activating and protective group in N-acyl-Pictet–Spengler reactions using methoxystyrenes. A short approach to racemic 1-benzyltetrahydroisoquinoline alkaloids

• Marco Keller,
• Karl Sauvageot-Witzku,
• Franz Geisslinger,
• Nicole Urban,
• Michael Schaefer,
• Karin Bartel and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2716–2725, doi:10.3762/bjoc.17.183

• activity. This is supported by the fact that the alkaloids investigated here bearing only hydroxy and small alkoxy residues, show no inhibitory effect on TPC2 as well. Our results further suggest that antiproliferative activity of benzylisoquinolines is connected to their inhibitory potency on TPC2