Anion–π catalysis on carbon allotropes

• M. Ángeles Gutiérrez López,
• Mei-Ling Tan,
• Giacomo Renno,
• Augustina Jozeliūnaitė,
• J. Jonathan Nué-Martinez,
• Javier Lopez-Andarias,
• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2023, 19, 1881–1894, doi:10.3762/bjoc.19.140

• ][86][87][88][89][90][91][92][93][94]. They serve as catch-and-release scaffolds in different variations, and, less frequently, as (photo)redox partners. Although they might contribute to these activities, anion–π interactions have not been considered. Anion–π catalysis on carbon nanotubes has been

Inline purification in continuous flow synthesis – opportunities and challenges

• Jorge García-Lacuna and
• Marcus Baumann

Beilstein J. Org. Chem. 2022, 18, 1720–1740, doi:10.3762/bjoc.18.182

• ). In another case, the authors opt to use stoichiometric quantities of reagents to avoid the use of cartridges, even if the performance is worse, to reduce cost and time [93]. Catch and release strategy An interesting approach regarding the use of resins is their application in catch and release

• purification via a catch and release strategy [96]. Additionally, functionalized residues can be used to perform a solid-state synthesis approach, such as in the synthesis of 2-aminopyridine derivatives starting from amino-iminium residues [97]. To improve on this technology, Baxendale and co-workers utilized

• ]. Another example for using this catch and release strategy would be when the product is trapped on silica due to its polarity prior to its release with a more polar solvent. This case is reported in the synthesis of iloperidone (Scheme 12) [107]. Though limited to applications with highly polar products

Inductive heating and flow chemistry – a perfect synergy of emerging enabling technologies

• Conrad Kuhwald,
• Sibel Türkhan and
• Andreas Kirschning

Beilstein J. Org. Chem. 2022, 18, 688–706, doi:10.3762/bjoc.18.70

• 180 °C at 4.5 MPa for 7.5 min. These conditions allowed to suppress the decomposition of the N-alkylation product 78 by using a 1/8“-reactor. The subsequent purification was realized by a clever catch and release protocol based on a silica column, yielding iloperidone (80, 67%). The tricyclic

• multistep flow synthesis of Iloperidone (80) accompanied with a “catch and release” purification protocol. Continuous two-step flow process consisting of Grignard reaction followed by water elimination being the last steps of a multistep flow synthesis of the hydrochloride salt of amitryptiline 84

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Synergy between supported ionic liquid-like phases and immobilized palladium N-heterocyclic carbene–phosphine complexes for the Negishi reaction under flow conditions

• Edgar Peris,
• Raúl Porcar,
• María Macia,
• Jesús Alcázar,
• Eduardo García-Verdugo and
• Santiago V. Luis

Beilstein J. Org. Chem. 2020, 16, 1924–1935, doi:10.3762/bjoc.16.159

• . A catch and release mechanism can be established favored by the presence of the supported ionic liquid-like phases. SILLPs with a relatively low loading of methylimidazolium units provided the most efficient systems to be used in conjunction with the immobilized NHC–Pd–RuPhos. Negishi reaction

The Shono-type electroorganic oxidation of unfunctionalised amides. Carbon–carbon bond formation via electrogenerated N-acyliminium ions

• Alan M. Jones and
• Craig E. Banks

Beilstein J. Org. Chem. 2014, 10, 3056–3072, doi:10.3762/bjoc.10.323

• ) induced a “temporarily soluble” droplet of the nucleophile that can then intercept the N-acyliminium ion. Electrosynthesis have been adapted to use solid-supported bases [47][48][49][50][51], performing the electrosynthesis on compounds directly attached to a catch and release solid-support [52], or

• and release cation pool method [42]. Schematic illustration of the anodic substitution reaction system using acoustic emulsification. Figure redrawn from reference [45]. Example of a chiral auxiliary Shono-oxidation intermediate [69]. Application of anodic oxidation to the generation of new carbon

• electrochemists to significantly progress this exciting and burgeoning field. Schematic of a cation flow system and also shown is the electrochemical microflow reactor reported by Suga et al. Figure redrawn from reference [30]. Example of a parallel laminar flow set-up. Figure redrawn from reference [38]. A catch

Camera-enabled techniques for organic synthesis

• Steven V. Ley,
• Richard J. Ingham,
• Matthew O’Brien and
• Duncan L. Browne

Beilstein J. Org. Chem. 2013, 9, 1051–1072, doi:10.3762/bjoc.9.118

Approaches towards the synthesis of 5-aminopyrazoles

• Ranjana Aggarwal,
• Vinod Kumar,
• Rajiv Kumar and
• Shiv P. Singh

Beilstein J. Org. Chem. 2011, 7, 179–197, doi:10.3762/bjoc.7.25

• -component, two-step “catch and release” solid-phase synthesis of 3,4,5-trisubstituted pyrazoles was reported which involved a base-promoted condensation of a 2-sulfonyl- or a 2-carbonyl-acetonitrile derivative (29 or 33) with an isothiocyanate and in situ immobilization of the resulting thiolate anion (30

• synthesis of 5-aminopyrazoles. Synthesis of 5-aminopyrazoles from resin supported enamine nitrile 25 as the starting material. Two-step “catch and release” solid-phase synthesis of 3,4,5-trisubstituted pyrazoles. Synthesis of pyrazolo[5,1-d][1,2,3,5]tetrazine-4(3H)-ones. Synthesis of the 5,5-ring system

Continuous flow based catch and release protocol for the synthesis of α-ketoesters

• Alessandro Palmieri,
• Steven V. Ley,
• Anastasios Polyzos,
• Mark Ladlow and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2009, 5, No. 23, doi:10.3762/bjoc.5.23

• esters 1a,c. Nitroolefinic esters 1a,c prepared under flow conditions (as described in Scheme 3). Supporting Information Supporting Information File 42: Supporting Information – Continuous flow based catch and release protocol for the synthesis of α-ketoesters Acknowledgements We gratefully acknowledge

• and release; flow synthesis; α-ketoesters; mesoreactor; polymer supported reagents; Introduction Organic synthesis is changing rapidly owing to the discovery of processes that challenge current dogma and lead to the invention of new chemical reactions [1][2]. Likewise, new synthesis tools are

• chemical syntheses [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. In this work we report the use of the Uniqsis FlowSyn™ continuous flow reactor [55] (Figure 1) to effect a flow-based preparation of α-ketoesters. The key feature of this process is the application of a catch and