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

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• 205 were accessed in moderate to excellent yields and also naphthyridine derivatives (205k and 205l) were synthesized. In the proposed mechanism, the initial deprotonation of HNBn2 by Ln[N(TMS)2]3 provided the lanthanide amide. Activation of the vinyl-substituted pyridin-3-amine 204 by the lanthanide

• amide gives a lanthanide–pyridine complex 206. Then, coordination and sequential insertion of C=C into the Ln–pyridine bond of 206 provided intermediate 207, which undergoes intermolecular protonation with 204 to afford the desired product 205 and regenerating the lanthanide species (Scheme 38b). C(sp2

Selective recognition of ATP by multivalent nano-assemblies of bisimidazolium amphiphiles through “turn-on” fluorescence response

• Rakesh Biswas,
• Surya Ghosh,
• Shubhra Kanti Bhaumik and
• Supratim Banerjee

Beilstein J. Org. Chem. 2020, 16, 2728–2738, doi:10.3762/bjoc.16.223

• involved in a number of essential biological functions including active transport and cell division [28][29]. For ATP detection, metal complexes using metal ions such as Zn(II), Cu(II) and lanthanide ions have been frequently employed [30][31][32][33][34][35]. A variety of other systems such as aptamers

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

• moulds, which could not be achieved with the blue laser [50]. Heterogeneous upconversion systems are generally crystalline nanomaterials comprising a host matrix of typically NaYF4, doped with a mixture of lanthanide ions, which act as light-absorbing sensitisers (e.g., Yb3+) and energy-combining

A photochemical determination of luminescence efficiency of upconverting nanoparticles

• Baptiste Amouroux,
• Clément Roux,
• Jean-Claude Micheau,
• Fabienne Gauffre and
• Christophe Coudret

Beilstein J. Org. Chem. 2019, 15, 2671–2677, doi:10.3762/bjoc.15.260

• efficiency of these green-emitting “nanolamps”. The agreement of the collected data with the previous published results validates this approach. Keywords: actinometry; diarylethene; lanthanide; photochemistry; upconverting nanoparticle; Introduction The photophysical property of converting low-energy light

• , typically near infrared (NIR), into high energy one thanks to noncoherent photon absorption is called “upconversion”. This phenomenon is exemplified by the lanthanide-based materials [1]. With the rapid developments of nanotechnology, upconverting Ln3+-based nanoparticles (UCNPs) have been reported for

• ], drug uncaging [11] to photodynamic therapy [12] and optogenetics [13][14]. Inorganic lanthanide based-UCNPs are classically formulated as a mixed fluoride NaREF4. Here, RE stands for a cocktail of trivalent rare-earth metal ions containing mostly photophysically inert metals (Y, Gd) and a few percent

A review of the total syntheses of triptolide

• Xiang Zhang,
• Zaozao Xiao and
• Hongtao Xu

Beilstein J. Org. Chem. 2019, 15, 1984–1995, doi:10.3762/bjoc.15.194

• 12 steps with 15% yield. Interestingly, in this synthesis only four intermediates needed to be purified. In 1999, Yang and co-workers reported an elegant chiral auxiliary-assisted, lanthanide triflate-catalyzed oxidative radical polycyclization of olefin-cation-based enantioselective synthesis of

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

A convenient and practical synthesis of β-diketones bearing linear perfluorinated alkyl groups and a 2-thienyl moiety

• Ilya V. Taydakov,
• Yuliya M. Kreshchenova and
• Ekaterina P. Dolotova

Beilstein J. Org. Chem. 2018, 14, 3106–3111, doi:10.3762/bjoc.14.290

• ]. Diketones bearing perfluorinated radicals are very important for the design of highly effective luminescent materials based on lanthanide coordination compounds. Substitution of aliphatic radicals by perfluorinated ones in the molecules of ligands led to a significant increase in luminescence intensity due

Revisiting ring-degenerate rearrangements of 1-substituted-4-imino-1,2,3-triazoles

• James T. Fletcher,
• Matthew D. Hanson,
• Joseph A. Christensen and
• Eric M. Villa

Beilstein J. Org. Chem. 2018, 14, 2098–2105, doi:10.3762/bjoc.14.184

• ][14][15][16][17], quinoline [18][19], pyridazine [20][21], phthalazine [22], benzimidazole [23], phenanthroline [24], bipyridine [25] and amine [26] subunits. The utility of such chelators in constructing coordination compounds has been demonstrated for a wide range of transition metal and lanthanide

Phosphodiester models for cleavage of nucleic acids

• Satu Mikkola,
• Tuomas Lönnberg and
• Harri Lönnberg

Beilstein J. Org. Chem. 2018, 14, 803–837, doi:10.3762/bjoc.14.68

Exploring mechanochemistry to turn organic bio-relevant molecules into metal-organic frameworks: a short review

• Vânia André,
• Sílvia Quaresma,
• João Luís Ferreira da Silva and
• M. Teresa Duarte

Beilstein J. Org. Chem. 2017, 13, 2416–2427, doi:10.3762/bjoc.13.239

• . Gabapentin was also used by Quaresma et al. [124] in the synthesis by manual grinding of seventeen new metal coordination networks with Y(III), Mn(II) and several lanthanide chlorides (LnCl3), Ln = La3+, Ce3+, Nd3+, and Er3+. Ten out of these compounds were structurally characterized and represent the first

Phosphonic acid: preparation and applications

• Charlotte M. Sevrain,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2017, 13, 2186–2213, doi:10.3762/bjoc.13.219

• 14, Figure 4), was assessed to complex indium [86] or terbium [87] with the aim to develop bone targeting and dosimetry. It was also employed to complex 89Y and applied as pH sensitive NMR probe [88], or as organic precursor of crystalline manganese, nickel [89] or lanthanide-containing hybrid

• reported as a chelator of 177Lu which was explored as a radiotracer that accumulates in bones [92]. These coordination properties were also applied to water treatment and to selectively extract lanthanide from water solutions [93], for nuclear waste treatment [94] or as sequestration or decorporation

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

• cyclodextrins, one with degrees of substitution in the 2–6 range, the other with degrees of substitution in the 6–10 range, are examined. Results with 33 water-soluble cationic substrates are reported. We also explored the possibility that the addition of paramagnetic lanthanide ions such as praseodymium(III

• resonances. Earlier studies with the CM-CDs demonstrated the effectiveness of adding paramagnetic lanthanide ions such as praseodymium(III) and ytterbium(III) to enhance the enantiomeric differentiation in the NMR spectra of cationic substrates [29][30][31][32]. The lanthanide cation binds to the anionic

• carboxymethyl group on the CM-CD and the magnetic field of the paramagnetic lanthanide ion perturbs the chemical shifts of the substrate bound in the cyclodextrin cavity by a through-space (pseudocontact) mechanism. The ability of paramagnetic lanthanide ions to improve the enantiomeric differentiation in the

Selective synthesis of thioethers in the presence of a transition-metal-free solid Lewis acid

• Federica Santoro,
• Matteo Mariani,
• Federica Zaccheria,
• Rinaldo Psaro and
• Nicoletta Ravasio

Beilstein J. Org. Chem. 2016, 12, 2627–2635, doi:10.3762/bjoc.12.259

• the fact that transition metal ions are strongly thiophilics, therefore most of metallic catalysts are poisoned by the presence of sulfur compounds. Lanthanide complexes such as Yb(OTf)3 are an exception [27] but only allylic and propargylic alcohols react under the reported conditions. The alkylation

Bright molecules for sensing, computing and imaging: a tale of two once-troubled cities

• A. Prasanna de Silva

Beilstein J. Org. Chem. 2015, 11, 2774–2784, doi:10.3762/bjoc.11.298

• naturally harnesses the diversity available in each of the three modules. For instance, the lumophore could be a fluorescent dye [3][24], a room temperature phosphor [25][26], or a lanthanide-based emitter [27][28]. Colleagues showed that even a quantum dot [29] would fit the bill. The receptor could be an

Recent advances in metathesis-derived polymers containing transition metals in the side chain

• Ileana Dragutan,
• Valerian Dragutan,
• Bogdan C. Simionescu,
• Albert Demonceau and
• Helmut Fischer

Beilstein J. Org. Chem. 2015, 11, 2747–2762, doi:10.3762/bjoc.11.296

• )s. Lanthanide-containing polymers Recently, new polynorbornenes of type 53, functionalized with terpyridine and carbazole moieties and integrating a europium complex in the pendant chains, were described by Rozhkov et al. [67]. They were obtained by a metathesis copolymerization with Grubbs 3rd

• between the metal and the organic polymer backbone and/or side chains is crucial for ensuring the desired properties for the hybrid material [68]. Indeed, when appraising luminescence of a series of polynorbornenes attaching various homoleptic bi- or trinuclear lanthanide salen complexes (with La, Nd, Yb

Easy access to heterobimetallic complexes for medical imaging applications via microwave-enhanced cycloaddition

• Nicolas Desbois,
• Sandrine Pacquelet,
• Adrien Dubois,
• Clément Michelin and
• Claude P. Gros

Beilstein J. Org. Chem. 2015, 11, 2202–2208, doi:10.3762/bjoc.11.239

• commercially available propargylamido-DOTA-tris(t-Bu)ester [29]. Complexation of 3 with a lanthanide was previously described by Borbas et al. [30]. Gd(DOTA) complex 10a, containing a pendant terminal alkyne group, was prepared by variation of a known procedure [29][31], as shown in Scheme 3. The complex was

Diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams

• Katherine M. Byrd

Beilstein J. Org. Chem. 2015, 11, 530–562, doi:10.3762/bjoc.11.60

• lanthanide metal. The authors were able to achieve the asymmetric 1,4-addition of dibenzyl malonate in good yields and enantioselectivies under these conditions (Scheme 27). Lewis acid catalysts have also been used to promote asymmetric 1,4-addition of radicals to α,β-unsaturated amides. Though there were a

• enantioselectivities when 30 mol % of the catalyst was used. Interestingly, when the Lewis acid is switched to the lanthanide triflate, Yb(OTf)3 or Y(OTf)2, the opposite configuration of the product was obtained (the S enantiomer was obtained vs. the R enantiomer that is obtained when MgBr2 is used). In 2001, the

First chemoenzymatic stereodivergent synthesis of both enantiomers of promethazine and ethopropazine

• Paweł Borowiecki,
• Daniel Paprocki and
• Maciej Dranka

Beilstein J. Org. Chem. 2014, 10, 3038–3055, doi:10.3762/bjoc.10.322

Come-back of phenanthridine and phenanthridinium derivatives in the 21st century

• Lidija-Marija Tumir,
• Marijana Radić Stojković and
• Ivo Piantanida

Beilstein J. Org. Chem. 2014, 10, 2930–2954, doi:10.3762/bjoc.10.312

Preparation of phosphines through C–P bond formation

• Iris Wauters,
• Wouter Debrouwer and
• Christian V. Stevens

Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106

• giving a platinum–phosphido complex. Subsequent nucleophilic attack on a Michael acceptor alkene was suggested to lead to a zwitterion intermediate. Addition of a protic additive was beneficial for the selectivity and reaction rate [95]. Several chiral cyclic phosphines were acquired via the lanthanide

• catalyzed intramolecular hydrophosphination of phosphinoalkenes. Scheme 15 shows the diastereoselective synthesis of 2,5-dimethylphospholanes 49 from 47 with a lanthanide catalyst 48 [122]. The common mechanism when using lanthanide [113] or alkaline earth metal [123] catalysts is based on the formation of

Synthesis and structure of trans-bis(1,4-dimesityl-3-methyl-1,2,3-triazol-5-ylidene)palladium(II) dichloride and diacetate. Suzuki–Miyaura coupling of polybromoarenes with high catalytic turnover efficiencies

• Jeelani Basha Shaik,
• Venkatachalam Ramkumar,
• Babu Varghese and
• Sethuraman Sankararaman

Beilstein J. Org. Chem. 2013, 9, 698–704, doi:10.3762/bjoc.9.79

• -metal and lanthanide metal chemistry [1][10][11]. Over the past few years they have gradually replaced the conventional phosphane ligands. The transition-metal complexes of these versatile ligands have been shown to be excellent catalysts for various organic transformations [9][10][11][12][13][14

Syntheses and applications of furanyl-functionalised 2,2’:6’,2’’-terpyridines

• Jérôme Husson and
• Michael Knorr

Beilstein J. Org. Chem. 2012, 8, 379–389, doi:10.3762/bjoc.8.41

• as N-donor ligands toward numerous main-group, transition-metal and lanthanide cations [3]. Coordination compounds LnM(tpy)m (n = 0–4; m = 1,2) ligated with terpyridine derivatives form stable assemblies due to the thermodynamic chelate effect. In the case of transition metal complexes, the σ-donor/π

• provide lanthanide complexes 56 and 57 (Scheme 10). The bromo-derivative 54 was further functionalised by cross-coupling reactions. Namely, the treatment of 54 with aminophenylacetylene in a Sonogashira reaction afforded terpyridine 58. The triple bond was then reduced by hydrogenation providing tpy 59

• . Finally, the hydrolysis of the ester moieties followed by complexation to Eu(III) yielded the lanthanide complex 65 (Scheme 12). This synthetic sequence was used to demonstrate the possibility to prepare labelled oligonucleotides starting from azido-functionalised ones and alkynyl-containing terpyridines

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

• −1 for Na+, 0.32 M−1 for K+ and 0.11 M−1 for Li+ in the presence of 10 equiv of the triflate salts. However, those oxacalixarenes form stronger complexes with transition, lanthanide and uranyl cations. Cragg employed the quartz-crystal-microbalance technique to investigate binding by Na+, K+ and Ca2

• Re(CO)3 to two deprotonated phenolic oxygen atoms as shown in Figure 16. Reaction with ester derivative 3k at 85 °C resulted in decomposition of the macrocycle. 4.1.4 Lanthanide complexation: The first study of the binding affinities of lanthanides for oxacalix[3]arenes was in 1995 when Hampton

• also shows that ketone 24 is a weak extracting agent, with a slight preference for Ag+. This is in agreement with the higher basicity of the carbonyl oxygen in the amide group compared with the ketone group. 4.2.4 Lanthanides: Marcos investigated the lanthanide extraction by both 17a [70] and 24 [39

Complete transfer of chirality in an intramolecular, thermal [2 + 2] cycloaddition of allene-ynes to form non-racemic spirooxindoles

• Kay M. Brummond and
• Joshua M. Osbourn

Beilstein J. Org. Chem. 2011, 7, 601–605, doi:10.3762/bjoc.7.70

• oxindoles into chiral non-racemic spirooxindoles containing an alkylidene cyclobutene moiety. The enantiomeric excesses were determined by chiral lanthanide shift NMR analysis and the transfer of chiral information from the allene to the spirooxindole was found to be greater than 95%. Keywords: alkylidene

• cyclobutene; allene; allenyloxindole; chiral lanthanide shift reagent; chiral transfer; Introduction The [2 + 2] cycloaddition reaction of allenes and alkynes provides rapid entry into synthetically challenging alkylidene cyclobutene ring systems. We, along with others, have demonstrated the intramolecular