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

• academic research and industrial applications. As a result, significant efforts have been devoted to the development of various methods for the reduction of nitroarenes [39]. Recent advancements in the catalytic reduction of nitroarenes largely rely on transition-metal catalysis through direct

Strategies in the synthesis of dibenzo[b,f]heteropines

• David I. H. Maier,
• Barend C. B. Bezuidenhoudt and
• Charlene Marais

Beilstein J. Org. Chem. 2023, 19, 700–718, doi:10.3762/bjoc.19.51

• transition metal (Ni, Fe, V) porphyrin catalysts and oxygen. Catalytic reduction (H2, Pd/C) affords 2,2'-diaminobibenzyl (20) in the subsequent step [28]. 1.2 Ring-closing via amine condensation The initial synthesis of 10,11-dihydro-5H-dibenzo[b,f]azepine (2a) was reported in 1899 by Thiele and Holzinger

• '-diaminobibenzyl (20). Synthesis of 10,11-dihydro-5H-dibenzo[b,f]azepine (2a) via amine condensation. Catalytic reduction of 10,11-dihydro-5H-dibenzo[b,f]azepine (2a). The Wagner–Meerwein rearrangement of acridin-9-ylmethanol (23) into 5H-dibenzo[b,f]azepine (1a). Oxidative ring expansion of 2-(9-xanthenyl

Combining the best of both worlds: radical-based divergent total synthesis

• Kyriaki Gennaiou,
• Antonios Kelesidis,
• Maria Kourgiantaki and
• Alexandros L. Zografos

Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1

• drastically the radical stability, nucleophilicity, and selectivity of 139 [73]. Furnishing of the common scaffold 130 can be carried out via an attack of intermediates of this type (e.g., 139) on Michael acceptors. Tosyl group deprotection of 130, followed by selenium anhydride oxidation and catalytic

• reduction of the amide using Wilkinson’s catalyst provided diastereoisomeric indole 131. Careful manipulation of the nitrile and alcohol side chains allowed selective cyclizations to the nitrogen atom of the indole core to conclude the total syntheses of 132–134. Samarium diiodide-mediated reductive

N-Arylphenothiazines as strong donors for photoredox catalysis – pushing the frontiers of nucleophilic addition of alcohols to alkenes

• Fabienne Speck,
• David Rombach and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2019, 15, 52–59, doi:10.3762/bjoc.15.5

• reduction potential of −3.0 V (vs SCE) the present novel N-phenylphenothiazine-based photoredox catalysts reach impressive excited state reduction potentials with up to −3.0 V (vs SCE) in case of catalyst 10. We applied the strongly reducing N-phenylphenothiazines 2, 10 and 11 for the photoredox catalytic

• reduction of α-methylstyrene (13a) as a less activated styrene that could not be addressed before. After optimization, the photoredox catalytic addition of methanol proceeded in quantitative yield within 20 h without any further additive, like triethylamine as electron shuttle. We could speed up the

Organometallic vs organic photoredox catalysts for photocuring reactions in the visible region

• Aude-Héloise Bonardi,
• Frédéric Dumur,
• Guillaume Noirbent,
• Jacques Lalevée and
• Didier Gigmes

Beilstein J. Org. Chem. 2018, 14, 3025–3046, doi:10.3762/bjoc.14.282

• interest for catalytic reduction of hydrogen gas [64]. Such an iron polypyridyl complex has also really good photoredox catalyst properties to initiate a polymerization upon sunlight exposure in a three-component system [68]. Functionalization of the ligand can change the photochemical properties of the

One hundred years of benzotropone chemistry

• Arif Dastan,
• Haydar Kilic and
• Nurullah Saracoglu

Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98

Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction

• Qing Yin,
• Qi Chen,
• Li-Can Lu and
• Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120

• reduction of 4-nitrophenol (4-NP) with an activity factor ka = 51.4 s−1 g−1, which is higher than some reported AgNP-containing composite materials. Keywords: catalytic reduction; hypercross-linking; porous polymers; silver nanoparticles; sugar; Introduction Hypercross-linked polymers (HCPs) are

• porous polymer SugPOP-1 is based on hemiacetal glucose, it was further postfunctionalized to embed the AgNPs into the material using an in situ chemical reduction of the freshly prepared Tollens’ reagent. The related catalytic reduction by the AgNPs/SugPOP-1 composite was also explored at room

• , the related catalytic activity of the composite tends to decrease with the increase in the size of the AgNPs. Therefore, the reaction time should not be too long. We found that the optimized loading reaction time was about 24 h. In the presence of excess BH4−, the catalytic reduction reaction mediated

Synthesis of 1-indanones with a broad range of biological activity

• Marika Turek,
• Dorota Szczęsna,
• Marek Koprowski and
• Piotr Bałczewski

Beilstein J. Org. Chem. 2017, 13, 451–494, doi:10.3762/bjoc.13.48

• -chloropropionyl chloride 174 followed by a intramolecular Friedel–Crafts alkylation afforded 1-indanones 178 (Scheme 51) [80]. A direct reaction of the latter with n-butylnitrite led to the formation of keto-oximes 179 which underwent a Pd/C catalytic reduction to give 2-amino substituted 1-indanones 180. Both

Conjugate addition–enantioselective protonation reactions

• James P. Phelan and
• Jonathan A. Ellman

Beilstein J. Org. Chem. 2016, 12, 1203–1228, doi:10.3762/bjoc.12.116

• the enantioselective reduction of α-substituted conjugate addition acceptors, including catalytic hydrogenation, multiple reviews have already appeared on this topic, and therefore asymmetric catalytic reduction will not be covered here [11][12][13]. Conjugate addition followed by terminal

A selective and mild glycosylation method of natural phenolic alcohols

• Mária Mastihubová and
• Monika Poláková

Beilstein J. Org. Chem. 2016, 12, 524–530, doi:10.3762/bjoc.12.51

• -benzyloxyphenyl)alkyl alcohol catalysed by Ag salts [9][18]. The final removal of the benzyl protecting group from the phenolic function of the aglycone by catalytic reduction can be however problematic in the case of more complex molecules containing for example double bonds (e.g., arenarioside) [30

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• a double nucleophilic substitution between tosylamine and 2,3-bis-chloromethylpyridine (1.112) followed by catalytic reduction of the resulting bicycle using palladium on carbon in acetic acid (Scheme 20). As the corresponding sulfonamide 1.113 was found to be a crystalline solid a resolution using

Reduction of benzylic alcohols and α-hydroxycarbonyl compounds by hydriodic acid in a biphasic reaction medium

• Michael Dobmeier,
• Josef M. Herrmann,
• Dieter Lenoir and
• Burkhard König

Beilstein J. Org. Chem. 2012, 8, 330–336, doi:10.3762/bjoc.8.36

• complexes [9][10][11][12][13]. Most procedures require a sequence of steps, e.g., the conversion of hydroxy groups into a chloride or bromide substituent and subsequent catalytic reduction with H2/Pt or the conversion into a tosylate and reduction with LiAlH4. The most commonly applied method is the Barton

Sordarin, an antifungal agent with a unique mode of action

• Huan Liang

Beilstein J. Org. Chem. 2008, 4, No. 31, doi:10.3762/bjoc.4.31

• -unsaturated ester, which was subjected to Pearlman hydrogenolysis of the benzyl group and selective catalytic reduction of the non-conjugated olefin with iridium black. The latter step proceeded in a predominately syn manner to afford intermediate 12, which was oxidized to cyclopentadiene 13 through TBS

Hydrogenation of aromatic ketones, aldehydes, and epoxides with hydrogen and Pd(0)EnCat™ 30NP

• Steven V. Ley,
• Angus J. P. Stewart-Liddon,
• David Pears,
• Remedios H. Perni and
• Kevin Treacher

Beilstein J. Org. Chem. 2006, 2, No. 15, doi:10.1186/1860-5397-2-15

• recycling of the catalyst problematic. Addition of NaOH or designing bimetallic catalysts in which one of the metals acts as poisoning agent, have also been reported. [8][9][10] Several metals (e.g. Pd, Pt, Ru) have been used in the literature for the selective heterogeneous catalytic reduction of aryl