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The application of biocatalysis has become essential in both academic and industrial domains for the asymmetric synthesis of chiral amines, and it serves as an alternative tool to transition‐metal catalysis and complements traditional chemical methods. It relies on the swift expansion of available processes, primarily as a result of advanced tools for enzyme discovery, combined with high‐throughput laboratory evolution techniques for optimizing biocatalysts. This concept paper explores the utilization of non‐conventional media such as ether‐type solvents, deep eutectic solvents, and micellar catalysis to enhance biocatalytic reactions for chiral amine synthesis. Each section focuses on the unique properties of these media, including their ability to stabilize enzymes, alter substrate solubility, and modulate enzyme selectivity. The paper aims to provide insights into how these innovative media can overcome traditional limitations, offering new avenues for sustainable and efficient chiral amine production through biocatalytic processes. [ABSTRACT FROM AUTHOR]

Wittig reaction between substituted phosphonium salts and (hetero)aromatic and alkyl carbonyl compounds in Deep Eutectic Solvents has been developed under a scalable and friendly protocol. Highly efficient reactions were successfully run with a wide range of bases including organic (DBU, LiTMP, t‐BuOK) and inorganic (NaOH, K2CO3) ones in ChCl/Gly 1 : 2 (mol/mol) as solvent under mild conditions, at room temperature and under air. The proposed protocol was applied to a wide range of substrates, including (hetero)aromatic aldehydes with substituents as halogens (I, Br, Cl), EDG (alkoxy, methyl), EWG (NO2, CF3) or reactive groups as CN, esters, and ketones. Vinylic, alkynyl and cycloalkyl, alicyclic and α,β‐unsaturated aldehydes can also be used. Highly electrophilic ketones gave good yields. The diastereoselectivity of the reaction is in complete agreement with the E/Z ratio predictable under traditional conditions. We demonstrated that the protocol is scalable to 2 g (5 mmol) of phosphonium salt, furthermore the proposed workup protocol allows to remove TPPO without need of additional chromatographic purification. [ABSTRACT FROM AUTHOR]

We herein report that the highly hydrophobic ether 4‐MeTHP constitutes a promising resource for the development of sustainable synthetic methodologies grounded on the use of organometallic reagents. The beneficial effects of 4‐MeTHP as reaction medium are illustrated in the organolithium‐promoted anionic ortho‐Fries rearrangement of 1,1'‐bi‐2‐naphthol (BINOL)‐based carbamates under bench‐type conditions. The use of 4‐MeTHP induces a remarkable and unexpected stability of the organolithiums species, enabling the efficient preparation of chiral (bis)carboxamide catalysts. Furthermore, superior performances of 4‐MeTHP than other environmentally responsible solvents are observed using the synthesized BINOL catalysts in the asymmetric addition of organozinc reagents to aldehydes. Spectroscopic studies in solution suggest that 4‐MeTHP plays a key role in these reactions by inducing the preferential formation of a reactive monomeric dinuclear complex. This methodology allows for the asymmetric assembly of enantioenriched secondary alcohols in good yields and high stereoselectivity, working at 0 °C and under air. [ABSTRACT FROM AUTHOR]

The first enantioselective reduction of 2‐substituted cyclic imines to the corresponding amines (pyrrolidines, piperidines, and azepines) by imine reductases (IREDs) in non‐conventional solvents is reported. The best results were obtained in a glycerol/phosphate buffer 1 : 1 mixture, in which heterocyclic amines were produced with full conversions (>99 %), moderate to good yields (22–84 %) and excellent S‐enantioselectivities (up to >99 % ee). Remarkably, the process can be performed at a 100 mM substrate loading, which, for the model compound, means a concentration of 14.5 g L−1. A fed‐batch protocol was also developed for a convenient scale‐up transformation, and one millimole of substrate 1 a was readily converted into 120 mg of enantiopure amine (S)‐2 a with a remarkable 80 % overall yield. This aspect strongly contributes to making the process potentially attractive for large‐scale applications in terms of economic and environmental sustainability for a good number of substrates used to produce enantiopure cyclic amines of high pharmaceutical interest. [ABSTRACT FROM AUTHOR]

The synthesis of acetals in acidic natural deep eutectic solvents (NADES), in which the solvent itself participates in the catalytic promotion of the reaction, is reported herein. The reaction is performed under feasible conditions, open air, without the need of external additives, catalysts or water‐removing techniques, and it is wide in scope. The products are easily recovered, and the reaction medium is fully recycled and reused without weakening of its catalytic activity after 10 times. Remarkably, the entire process has been realized on gram scale. [ABSTRACT FROM AUTHOR]

A straightforward protocol to promote the tetrahydropyranylation of alcohols, using for the first time bioinspired acidic natural deep eutectic solvents (NADESs) as non‐innocent reaction media under mild reaction conditions, was reported. This approach enables the preparation of several tetrahydropyranyl (THP) ethers starting from primary, secondary and tertiary alcohols in short reaction times and with high levels of chemoselectivity, working under air and without the need of additional catalyst. The sustainability of the methodology was further highlighted by its scalability and the easy recyclability of the NADES, allowing multigram preparations of THP ethers without any loss of the catalytic activity of the reaction media up to ten recycling steps. Telescoped, one‐pot tetrahydropyranylation/nucleophilic acyl substitution transformations using the same eutectic mixture were also demonstrated. [ABSTRACT FROM AUTHOR]

A straightforward and efficient protocol to promote the metalation/anionic Fries rearrangements of O‐aryl carbamates, using for the first time a lithium amide as metalating agent under aerobic/ambient‐friendly reaction conditions, is reported. This approach enables the sustainable preparation of salicylamide derivatives with high levels of chemoselectivity within ultrafast reaction times, working at room temperature in the presence of air/moisture, and using environmentally responsible cyclopentyl methyl ether as a solvent. Furthermore, the regioselective manipulation of O‐2‐tolyl carbamates has been accomplished using interchangeably alkyllithiums or lithium amides, with an unexpected beneficial contribution from the employment of biorenewable protic eutectic mixtures as non‐innocent reaction media. [ABSTRACT FROM AUTHOR]

Summary: Strigolactones (SLs) are plant hormones and important signalling molecules required to promote arbuscular mycorrhizal (AM) symbiosis. While in plants an α/β‐hydrolase, DWARF14 (D14), was shown to act as a receptor that binds and cleaves SLs, the fungal receptor for SLs is unknown.Since AM fungi are currently not genetically tractable, in this study, we used the fungal pathogen Cryphonectria parasitica, for which gene deletion protocols exist, as a model, as we have previously shown that it responds to SLs. By means of computational, biochemical and genetic analyses, we identified a D14 structural homologue, CpD14.Molecular homology modelling and docking support the prediction that CpD14 interacts with and hydrolyses SLs. The recombinant CpD14 protein shows α/β hydrolytic activity in vitro against the SLs synthetic analogue GR24; its enzymatic activity requires an intact Ser/His/Asp catalytic triad. CpD14 expression in the d14‐1 loss‐of‐function Arabidopsis thaliana line did not rescue the plant mutant phenotype. However, gene inactivation by knockout homologous recombination reduced fungal sensitivity to SLs.These results indicate that CpD14 is involved in SLs responses in C. parasitica and strengthen the role of SLs as multifunctional molecules acting in plant–microbe interactions. [ABSTRACT FROM AUTHOR]

Strigolactones are a class of carotenoid‐derived plant hormones, which impact many functions of plant metabolism in response to environmental stress. They also act as exogenous signals perceived by both mycorrhizal fungi and parasitic plants. The peculiar chemical skeleton of these molecules and their mode of action in plants inspired possible applications in biomedical fields. In this minireview, an overview of the most recent applications of Strigolactones and analog derivatives as anticancer, anti‐inflammatory, and antiviral drugs is described. [ABSTRACT FROM AUTHOR]

We report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromatic amides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the notorious over‐addition reaction. Detailed DFT calculations and NMR investigations support the experimental results. The described methodology was proven to be amenable to scale‐up and recyclability protocols. Contrasting classical procedures carried out under inert atmospheres, this work lays the foundation for a profound paradigm shift of the reactivity of carboxylic acid amides with organolithiums, with ketones being straightforwardly obtained by simply combining the reagents under aerobic conditions and with no need of using previously modified or pre‐activated amides, as recommended. [ABSTRACT FROM AUTHOR]

The selective formal insertion (homologation) of a carbon unit bridging the two trifluoroacetamidoyl chlorides (TFAICs) units is reported. The tactic is levered on a highly chemoselective homologation–metalation–acyl nucleophilic substitution sequence which precisely enables to assemble novel trifluoromethylated β‐diketiminates within a single synthetic operation. Unlike previous homologations conducted with LiCH2Cl furnishing aziridines, herein we exploit the unique capability of iodomethyllithium to act contemporaneously as a C1 source (homologating effect) and metalating agent. The mechanistic rationale grounded on experimental evidences supports the hypothesized proposal and, the structural analysis gathers key aspects of this class of valuable ligands in catalysis. [ABSTRACT FROM AUTHOR]

The gold(I)‐catalysed cyclization of N‐tosyl‐protected 5‐benzyl‐6‐((trimethylsilyl)ethynyl)‐1,2,3,4‐tetrahydropyridines, prepared by the Sonogashira coupling of lactam‐derived enol triflates, provides tetrahydrobenzo[g]quinolines whose skeleton represents a recurrent motif in natural compounds. The Au(I)‐catalysed reaction is carried out with (C6F5)3PAuCl/AgNTf2 as the catalyst system and proceeds via a 6‐exo‐dig cyclization to form an exocyclic double bond, which eventually isomerises to the aromatic tetrahydrobenzo[g]quinoline. The mode of cyclization is discussed and supported by DFT calculations. [ABSTRACT FROM AUTHOR]

Natural products containing a N‐heterocycle motif are widespread in nature and medicinal plants, in particular, have proved to be a source of almost unlimited N‐derived structures with high molecular diversity. Because of their intrinsic potential for use in both biomedical and agricultural applications, there is a general need for new compounds and for the synthesis of 'natural‐inspired' analogues. Importantly, transition of a natural product from discovery to a 'market lead' is associated with an increasingly challenging demand for more of the compound, which cannot be met by isolation from natural plant sources, often due to low extraction yields and uneven availability of the plant source itself. Synthesis remains the most reliable approach to provide valuable products for the market. In this review, a comprehensive overview of our contribution to synthetic access to N‐derived natural products is given. Major strengths of the proposed methodologies are discussed critically. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A small library of carborane‐BODIPY/aza‐BODIPY dyads were efficiently synthesized by means of a novel convergent synthetic approach, the key step of which is a Pd‐catalyzed Heck coupling reaction. The structural characterization and photoluminescence properties of the newly synthesized dyads were evaluated. The presence of the carborane did not significantly alter the photophysical patterns of the BODIPY or aza‐BODIPY in the final fluorophores, but it produced a decrease of the emission fluorescent quantum yields that was in the range from 1.4 % for aza‐BODIPY to 48 % for BODIPY‐dyads. The carborane‐BODIPY dyads were successfully incorporated into cells, especially compounds 2, 4 and 13, demonstrating their cytoplasmic localization. The fluorescent and biocompatibility properties make these compounds good candidates for in vitro cell tracking. The efficient Pd‐catalyzed Heck coupling reaction between BODIPY, aza‐DIPYs and styrenyl carboranes leads to a small library of carborane‐BODIPY/aza‐BODIPY dyads. Their fluorescence properties and internalization by HeLa cells make these compounds good candidates for in vitro cell tracking. [ABSTRACT FROM AUTHOR]

Abstract: Palladium(0)‐catalysed hydro‐alkylation or ‐alkenylation of alkoxyallenes with N‐tosylhydrazones gives direct access to conjugated and skipped 1‐alkoxydienes with high efficiency and excellent functional‐group compatibility. The reaction is proposed to involve the in situ‐formed t‐butanol as proton source in the key step of the allylpalladium(II) species generation. Moreover, lithium iodide or iodobenzene are employed as an unprecedented iodide (I−) reservoir to sustain the catalytic cycle. [ABSTRACT FROM AUTHOR]

Strigolactones are a class of natural and synthetic compounds that in the past decade have been exciting the scientific community not only for their intriguing biological properties but also for their potential applications in agriculture. These applications range from their use as hormones to modify and/or manage plant architecture, to their use as stimulants to induce seed germination of parasitic weeds and thus control their infestation by a reduced seed bank, to their use as 'biostimulants' of plant root colonisation by arbuscular mycorrhizal fungi, improving plant nutritional capabilities, to other still unknown effects on microbial soil communities. More recently, these compounds have also been attracting the interest of agrochemical companies. In spite of their biological attractiveness, practical applications are still greatly hampered by the low product yields obtainable by plant root exudates, by the costs of their synthesis, by the lack of knowledge of their off-target effects and by the not yet specified or properly identified legislation that could regulate the use of these compounds, depending on the agricultural purposes. The aim of this article is to discuss, in the light of current knowledge, the different scenarios that might play out in the near future with regard to the practical application of strigolactones. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The gold(I)-catalysed reaction of N-Boc-protected 6-alkynyl- 3,4-dihydro-2H-pyridines, which gives synthetically useful vinylogous amides (β-enaminones), has been studied in detail, in order to optimize the reaction conditions, enlarge the scope and gain insight into the mechanism and the structural features that selectively favour the 6-endo-dig oxyauration of the triple bond. Experimental studies and DFT calculations demonstrate that the 6-endo-dig approach is exclusive with substituted alkynes, whereas with terminal alkynes the 5- exo-dig cyclization prevails, despite the large angle (120°) at C-6. The same selectivity was observed with N-Cbz-protected 2-alkynylpiperidines. With these compounds, β-amino ketones are obtained as a consequence of the 6-endo-dig attack onto a substituted triple bond. Sedamine alkaloids are easily obtained by this approach. [ABSTRACT FROM AUTHOR]

A Mizoroki-Heck-heteroannulation cascade reaction has been used to prepare substituted dihydrobenzofurans and indolines in good yields by the reaction between functionalised alkoxy-1,3-dienes and several o-iodophenols or protected o-iodoanilines. [ABSTRACT FROM AUTHOR]

Front Cover: Gold(I)-Catalysed Hydroarylation of Lactam-Derived Enynes as an Entry to Tetrahydrobenzo[g]quinolines (Eur. J. Org. The fruit represents tetrahydrobenzo[ I g i ]quinolines, and the chemist is going to add it to other fruits he has already collected from the -valerolactam tree. Indeed, the gold-catalysed synthesis of tetrahydrobenzo[ I g i ]quinolines enlarges the palette of molecular scaffolds accessible in few steps from the same simple lactam precursor. [Extracted from the article]

The article presents chemical equations related to the article "Synthesis of Vinylogous Amides by Gold(I)-Catalyzed Cyclization of N-Boc-Protected 6-Alkynyl-3,4-dihydro-2H-pyridines" by A. Oppedisano and others, published in the periodical "Journal of Organic Chemistry" in 2013.