Synthesis of N-acetyl diazocine derivatives via cross-coupling reaction

• Thomas Brandt,
• Pascal Lentes,
• Jeremy Rudtke,
• Michael Hösgen,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2025, 21, 490–499, doi:10.3762/bjoc.21.36

• diazocines 13 and 21 were also investigated in aqueous solution (13 and 21 in aqueous PBS buffer solution at pH 7.4 250 µM, 21 at pH 3.5 250 µM, 13 at pH 9 250 µM). Benzoic acid derivative 13 was representatively chosen for polar aromatic substitution and the amino derivative 21 for non-aromatic substitution

Organocatalytic kinetic resolution of 1,5-dicarbonyl compounds through a retro-Michael reaction

• James Guevara-Pulido,
• Fernando González-Pérez,
• José M. Andrés and
• Rafael Pedrosa

Beilstein J. Org. Chem. 2025, 21, 473–482, doi:10.3762/bjoc.21.34

• entry 2 versus entry 6 in Table 2). Furthermore, we studied the effect of using an organic acid as the co-catalyst for forming the enamine intermediate from 1 and for the retro-Michael reaction. We observed that benzoic acid (BA) as a co-catalyst provides a lower er than that achieved with PNBA as a co

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

• Laura D’Andrea and
• Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

• that, up to 24 hours, this method shows some degree of functional group tolerance, as the amido and carboxylic acid functionalities of benzamide and benzoic acid, were left untouched, and the starting materials were finally fully recovered. 1-Bromo-4-nitrobenzene (8a) and 3-chlorophenol were used to

• reductive methods used to date for the synthesis of substituted phenethylamines from their α,β-unsaturated nitroalkene analogues. Furthermore, the NaBH4/CuCl2 system is effective at reducing nitro and ester functionalities on aromatic structures, while leaving intact benzoic acid, amido- and halogenated

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• , and iodination of the gemfibrozil aromatic ring by reacting them with the corresponding nucleophiles. Notably, reactions with phenol, thiophenol and benzoic acid using salts 71 in the presence of t-BuOK led to the corresponding products 72 with 61%, 69%, and 77% yields, respectively (Scheme 28). These

Catalysing (organo-)catalysis: Trends in the application of machine learning to enantioselective organocatalysis

• Stefan P. Schmid,
• Leon Schlosser,
• Frank Glorius and
• Kjell Jorner

Beilstein J. Org. Chem. 2024, 20, 2280–2304, doi:10.3762/bjoc.20.196

• physicochemical descriptors. A prominent early example are Hammett parameters, developed in 1937 [26][27], that relate substituent parameters to the equilibrium constant of the deprotonation of a substituted benzoic acid. The derived substituent parameters are used to gain insight into the mechanism of reactions

Oxidation of benzylic alcohols to carbonyls using N-heterocyclic stabilized λ³-iodanes

• Thomas J. Kuczmera,
• Pim Puylaert and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 1677–1683, doi:10.3762/bjoc.20.149

• oxidation of the alcohol. Only small amounts of benzoic acid 4a’ were observed in all reactions with additional AlCl3, suggesting that the additive inhibits the previously observed overoxidation. Surprisingly AlCl3 activated the cyclic tetrazole iodane 1a but had almost no influence on the reactivity of the

Generation of alkyl and acyl radicals by visible-light photoredox catalysis: direct activation of C–O bonds in organic transformations

• Mithu Roy,
• Bitan Sardar,
• Itu Mallick and
• Dipankar Srimani

Beilstein J. Org. Chem. 2024, 20, 1348–1375, doi:10.3762/bjoc.20.119

• iridium photocatalyst [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 leads to excited-state *[Ir(III)], Ered (*[Ir(III)]/[Ir(II)]) = +1.21 V, possessing sufficient energy to oxidize PPh3, forming the triphenylphosphine radical cation. Subsequently, benzoic acid undergoes deprotonation facilitated by a base, producing

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

• Naoki Miyamoto,
• Daichi Koseki,
• Kohei Sumida,
• Elghareeb E. Elboray,
• Naoko Takenaga,
• Ravi Kumar and
• Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

• a cartridge filled with powdered oxone® for in situ generation of bis(trifluoroacetoxyiodo)arenes and their reaction with electron-rich arene or arylboronic acid [19] (Scheme 1B). Carboxylic acids, such as acetic acid and benzoic acid, characterized by substantial difference in pKa values when

• 5b–f was explored with benzoic acid (6a) and 1,3,5-trimethoxybenzene (Scheme 5B). Iodosoarenes with electron-rich (5b, 5c, 5f), electron-deficient (5d), bromo (5e), and sterically hindered substituents (5f) were applicable to give the corresponding aryl(TMP)iodonium(III) benzoates 7ba–fa in 63–93

Synthesis of new representatives of A₃B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations

• Victoria M. Alpatova,
• Evgeny G. Rys,
• Elena G. Kononova and
• Valentina A. Ol'shevskaya

Beilstein J. Org. Chem. 2024, 20, 767–776, doi:10.3762/bjoc.20.70

• the ability of the amino group in porphyrin 5 to enter acylation reactions with 4-(N-maleimido)benzoyl chloride (8, prepared in situ from 4-(N-maleimido)benzoic acid (9) and oxalyl chloride) and chloroacetyl chloride (10) with the aim of using these compounds for further functionalization. The

Entry to new spiroheterocycles via tandem Rh(II)-catalyzed O–H insertion/base-promoted cyclization involving diazoarylidene succinimides

• Alexander Yanovich,
• Anastasia Vepreva,
• Ksenia Malkova,
• Grigory Kantin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2024, 20, 561–569, doi:10.3762/bjoc.20.48

• by mild synthetic conditions and high or good yields of the target compounds after two steps. The limitations of the method were demonstrated by unsuccessful attempts to carry out the cyclization of ОН-insertion products derived from 2-(bromomethyl)benzoic acid, 2-bromoethanol, and 2-(2-bromoethoxy

• reaction products using diazo reagent 1b as an example, but we failed to observe the formation of spirocyclic cyclization products as a result of intramolecular substitution of the bromine atom (Scheme 7). For example, during the attempted cyclization of compound 18, obtained from 2-(bromomethyl)benzoic

• acid (17), the formation of a complex mixture was observed, the main component of which turned out to be phthalide (19). The use of 2-bromoethanol (20) gave a similar result – compound 21 was transformed under the action of DBU into a multicomponent mixture of unidentifiable compounds. Judging from the

Copper-catalyzed multicomponent reaction of β-trifluoromethyl β-diazo esters enabling the synthesis of β-trifluoromethyl N,N-diacyl-β-amino esters

• Youlong Du,
• Haibo Mei,
• Ata Makarem,
• Ramin Javahershenas,
• Vadim A. Soloshonok and
• Jianlin Han

Beilstein J. Org. Chem. 2024, 20, 212–219, doi:10.3762/bjoc.20.21

• side reactions was carried out with benzyl 3-amino-4,4,4-trifluorobutanoate (1a) and benzoic acid (3a) as model substrates. The initial reaction of amine 1a and acid 3a in acetonitrile in the presence of diazotization reagent tert-butyl nitrite with CuI (10 mol %) as catalysts for 2.5 h at room

• groups, including alkyl (4a–e), halogen (4h–l), and phenyl (4m), were all suitable substrates for this reaction. However, the benzoic acid with ortho-substituent did not afford the expected product (4f) mainly due to the steric hindrance effect. Notably, substrates with electron-withdrawing groups (4h–l

• , 76–86% yields) provided better chemical yields in this reaction compared with those containing electron-donating groups (4b–e, 31–84% yields). For the case with a strong electron-donating group (methoxy, 3g) only traces of 4g were produced. Besides benzoic acid, the current Cu-catalyzed reaction was

Radical chemistry in polymer science: an overview and recent advances

• Zixiao Wang,
• Feichen Cui,
• Yang Sui and
• Jiajun Yan

Beilstein J. Org. Chem. 2023, 19, 1580–1603, doi:10.3762/bjoc.19.116

• photooxidation of polystyrene in the presence of FeCl3 as a radical source (Scheme 21a) [202]. A molar yield of 23% benzoyl small molecules was achieved. Reisner and co-workers employed a similar approach but using aromatic ketones as photocatalyst (Scheme 21b) [203]. Benzoic acid and other aromatic small

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• with mCPBA produced the epoxide 13.3. Then, the addition of benzoic acid in the presence of acid catalysis produced an ester that was saponified to yield the diol 13.4. A three-step sequence is applied to produce compound 13.5 that features a secondary alcohol protected with a benzyl group. Then, the

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

• reaction; however, the reaction was also viable with weakly acidic compounds (pKa < 8). There was no evidence of free carbenes being involved, and competition experiments showed that both electron-rich and electron-poor benzoic acids reacted faster than benzoic acid, which suggested that both proton

Photocatalytic sequential C–H functionalization expediting acetoxymalonylation of imidazo heterocycles

• Deepak Singh,
• Shyamal Pramanik and
• Soumitra Maity

Beilstein J. Org. Chem. 2023, 19, 666–673, doi:10.3762/bjoc.19.48

• ]. Finally, the reaction of 5 with benzoic acid and zinc acetate (in a 1:1 ratio) under standard reaction protocol resulted in the competitive formation of products 4a and 10 (Scheme 3E), indicating the susceptibility of other acids towards this method. These results, along with the Stern–Volmer fluorescence

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

• ‒H borylation, with an initial B‒Y/B‒H transborylation activating the precatalyst [62][63][64][65]. Zhang showed that benzoic acid decomposed HBpin to BH3 in situ to catalyse the C2‒H borylation of indoles (Scheme 4b) [66][67]. Gellrich reported the bis(pentafluorophenyl)borane-catalysed dimerisation

• of heterocycles and the proposed mechanism. b) Benzoic acid-promoted C‒H borylation of N-heterocycles and the proposed mechanism, where the active catalyst BH3 was formed in situ from HBpin decomposition. Bis(pentafluorophenyl)borane-catalysed dimerisation of allenes and the proposed mechanism

Friedel–Crafts acylation of benzene derivatives in tunable aryl alkyl ionic liquids (TAAILs)

• Swantje Lerch,
• Stefan Fritsch and
• Thomas Strassner

Beilstein J. Org. Chem. 2023, 19, 212–216, doi:10.3762/bjoc.19.20

• %, with minor formation of the ortho-isomer when using benzoic acid anhydride. Bromobenzene, which is electron poor and less reactive towards acylation, was also used as a substrate in the acylation reaction, but no product was observed. This indicates that the ionic liquid 6, having the same substituent

Sequential hydrozirconation/Pd-catalyzed cross coupling of acyl chlorides towards conjugated (2E,4E)-dienones

• Benedikt Kolb,
• Daniela Silva dos Santos,
• Sanja Krause,
• Anna Zens and
• Sabine Laschat

Beilstein J. Org. Chem. 2023, 19, 176–185, doi:10.3762/bjoc.19.17

• ). While 4-methyl-benzoic acid chloride (26b) behaved similarly to benzoyl chloride (26a) giving 27ab in a slightly higher yield of 57% (Table 4, entry 2), the yield of 27ac dropped to only 17% upon use of the corresponding 2-methylbenzoyl chloride (26c) (Table 4, entry 3). By attaching further electron

Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies

• Attila Palágyi,
• Jindřich Jindřich,
• Juraj Dian and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140

• Cannizaro’s reaction. At pH 12.80, the benzaldehyde was fully converted to benzyl alcohol and benzoic acid after 5 days. Static headspace analysis We first determined the Henry law constants and the formation constants with β-CD of three selected aldehydes (Table 1). As can be seen from Table 1, the studied

Synthetic strategies for the preparation of γ-phostams: 1,2-azaphospholidine 2-oxides and 1,2-azaphospholine 2-oxides

• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 889–915, doi:10.3762/bjoc.18.90

• -(diethoxyphosphoryl)benzoic acid (198) and amine derivatives. They first converted 2-(diethoxyphosphoryl)benzoic acid (198) into its anhydride 1-ethoxy-3H-benzo[c][1,2]oxaphosphol-3-one 1-oxide (199) by treatment with thionyl chloride under nitrogen. The mixed anhydride 199 was further treated with phosphorus

BINOL as a chiral element in mechanically interlocked molecules

• Matthias Krajnc and
• Jochen Niemeyer

Beilstein J. Org. Chem. 2022, 18, 508–523, doi:10.3762/bjoc.18.53

• were coupled with a benzoic acid-based stopper using N,N′-diisopropylcarbodiimide (DIC) and tributylphosphine (26–75% yield). The isolated rotaxanes were then used for subsequent reductive N-alkylation to obtain the tert-amine-type rotaxanes (R)-29a–f in yields of 67–92%. Finally, dimethyldioxirane

New efficient synthesis of polysubstituted 3,4-dihydroquinazolines and 4H-3,1-benzothiazines through a Passerini/Staudinger/aza-Wittig/addition/nucleophilic substitution sequence

• Long Zhao,
• Mao-Lin Yang,
• Min Liu and
• Ming-Wu Ding

Beilstein J. Org. Chem. 2022, 18, 286–292, doi:10.3762/bjoc.18.32

• Abstract A new efficient synthesis of polysubstituted 3,4-dihydroquinazolines and 4H-3,1-benzothiazines via sequential Passerini/Staudinger/aza-Wittig/addition/nucleophilic substitution reaction has been developed. The three-component Passerini reactions of 2-azidobenzaldehydes 1, benzoic acid (2), and

• -azidobenzaldehyde (1a), benzoic acid (2a) and tert-butyl isocyanide (3a) as the reactants (Scheme 2). When a mixture of 1a, 2a, and 3a in CH2Cl2 was stirred at room temperature for 48 h, the three-component Passerini reaction was carried out smoothly and the azide 4a (R = Ph) was finally obtained in 87% yield

• product 8a was 53%. Therefore, the reaction conditions of entry 1 in Table 1 were optimal for the above transformation. The optimal reaction conditions were then utilized for the sequential reactions of different 2-azidobenzaldehydes 1, benzoic acid (2a), isocyanides 3, isocyanates and secondary amines

Diametric calix[6]arene-based phosphine gold(I) cavitands

• Gabriele Giovanardi,
• Andrea Secchi,
• Arturo Arduini and
• Gianpiero Cera

Beilstein J. Org. Chem. 2022, 18, 190–196, doi:10.3762/bjoc.18.21

• attempted starting from the known dioctyloxydinitro derivative DN (Scheme 1) [33]. Reduction of the nitro groups with hydrazine, in the presence of catalytic amounts of Pd/C (10 mol %) led to the corresponding diamino intermediate. This latter could be subsequently reacted with the desired phosphino benzoic

• acid derivative through a user-friendly amide coupling in the presence of EDC·HCl and catalytic amounts of DMAP in CH2Cl2. Under these conditions, the corresponding diphosphine intermediates A (para), B (meta), and C (ortho) were isolated in moderate yields. Finally, gold(I) catalysts could be obtained

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

• logarithmically related to the measured acidities for the parent benzoic acid and for a series of para and meta-substituted derivatives for a solution in water at 25.0 °C. In this initial study, ortho-substituents were avoided due to the possibility of steric interactions superimposed on the inductive ones. The

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

• Togni’s reagent, is ideal because of its stability, low toxicity, and cost [148]. In terms of scope, the electronic nature of the benzoic acid had no effect on the reaction. On the other hand, only electron-rich styrene derivatives