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In conclusion, we successfully realized the first vinylogous Catellani reaction of 4-iodo-2-quinolones with benzyl alcohols bearing a tertiary benzyl moiety. By using this method, a variety of chromeno-2-quinolones, which are analogs of the natural alkaloid benzosimuline, were synthesized in moderate to high yields. The Catellani reaction is a powerful strategy that allows the expeditious synthesis of highly substituted arenes, which are not easily accessible through traditional transition‐metal‐catalyzed cross‐coupling reactions. This borono‐Catellani reaction was promoted by cooperative catalysis between Pd (OAc) 2 and the inexpensive 5‐norbornene‐2‐carbonitrile. Practicality is the striking feature of the reaction: it is run open to air at ambient temperature and no phosphine ligand is needed. We report a cooperative catalytic system comprising a Pd II complex, XPhos, and the potassium salt of 5‐norbornene‐2‐carboxylic acid that enables the use of epoxides as alkylating reagents in the Catellani reaction, thereby expanding the existing paradigm of this powerful transformation.

Catellani reaction

1997, 36, 119. Modular and Stereoselective Synthesis of C-Aryl Glycosides via Catellani Reaction | Journal of the American Chemical Society. In this work, we describe a Catellani-type C–H glycosylation to provide rapid access to various highly decorated α-C-(hetero)aryl glycosides in a modular and stereoselective manner (>90 examples). This borono-Catellani reaction was promoted by cooperative catalysis between Pd(OAc) 2 and the inexpensive 5-norbornene-2-carbonitrile. Practicality is the striking feature of the reaction: it is run open to air at ambient temperature and no phosphine ligand is needed.

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In book: Name Reactions (pp.73-76) Authors: Jie Jack Li. Request full-text PDF The Catellani reaction is known as a powerful strategy for the expeditious synthesis of highly substituted arenes and benzo‐fused rings, which are usually difficult to access through traditional cross‐coupling strategies. It utilizes the synergistic interplay of palladium and norbornene catalysis to facilitate sequential ortho C−H functionalization Historically, Catellani reactions have been limited to liquid or solid reagents. This can be ascribed to the fact that the use of gaseous olefins has long been avoided due to safety concerns (i.e., pressurized headspace and leakages) and process constraints (i.e., gas–liquid mass‐transfer limitations).

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HG Cheng, S Chen, R Chen, Q Zhou. Angewandte Chemie International Edition 58 (18), 5832-5844, 2019.

The Catellani reaction is catalyzed by palladium and norbornene, although in most cases superstochiometric amounts of norbornene are used to allow the reaction to proceed at a reasonable rate. The generally accepted reaction mechanism, as outlined below, is intricate and believed to proceed via a series of Pd(0), Pd(II), and Pd(IV) intermediates, although an alternative Reported is a novel palladium(II)-initiated Catellani-type reaction that utilizes widely accessible aryl boronic acids as the substrates instead of aryl halides, thereby greatly expanding the existing scope of this powerful transformation. This borono-Catellani reaction was promoted by cooperative c … Abstract A palladium-catalyzed and norbornene-mediated Catellani reaction was developed through ortho-acylation and ipso-alkynylation for the aryl iodides. Acyl chlorides were used as acylation reagents and phenylpropiolic acids were used as termination reagents respectively in this transformation. As a result, the reactivity of these three different compounds matched well and this unreported 2017-11-30 Achieving high selectivity through multiple C–H functionalization is a challenging task. In this issue of Chem, Lumb, Luan, and co-workers disclose a clever strategy taking advantage of steric remote effects for the synthesis of poly-substituted arenes through a 4-component Catellani reaction with remarkable regio- and chemoselectivity by using readily available reagents.
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This borono-Catellani reaction was promoted by cooperative catalysis between Pd(OAc) 2 and the inexpensive 5-norbornene-2-carbonitrile. Practicality is the striking feature of the reaction: it is run open to air at ambient temperature and no phosphine ligand is needed. Through application of the Catellani reaction, a great number of diverse scaffolds have been synthesized in one pot from simple starting materials. Over the past decade, this methodology has proven useful for the rapid generation of complexity in organic synthesis.

The potassium salt of inexpensive 5‐norbornene‐2‐carboxylic acid acts as both mediator and base Reaction mechanism. The Catellani reaction is catalyzed by palladium and norbornene, although in most cases superstochiometric amounts of norbornene are used to allow the reaction to proceed at a reasonable rate. [3] The generally accepted reaction mechanism, as outlined below, is intricate and believed to proceed via a series of Pd(0), Pd(II), and Pd(IV) intermediates, although an alternative The Pd(0)-initiated asymmetric Catellani-type reactions enabled by chiral smNBEs was further expanded to asymmetric ortho arylation reaction by Zhou group very recently (Scheme 13). 46 The C2 ethyl ester-substituted N21* gave the highest enantioselectivity (96% ee), while the methylamide-substituted N12* afforded 86% ee and diminished reactivity.
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The Catellani reaction — a palladium-catalysed C–H functionalization reaction mediated by norbornene — was first reported in 1997. The capacity to functionalize both the ortho and ipso positions of ABSTRACT: The Catellani reaction provides a facile and eﬃcient method for the synthesis of multifunctionalized arenes. However, the use of Pd(0) catalysts restricts the scope of accessible products. We have developed a Pd(II)-catalyzed, Catellani-type reaction utilizing arylboronic acids as the substrates for the ﬁrst time.

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Key words Catellani reaction, cooperative catalysis, alkyl tosylates, 5-norbornene-2-carbonitrile, polysubstituted arenes The development of straightforward strategies to as-semble complex molecular scaffolds represents one of the central tasks in modern organic synthesis.1 Therein, the 2018-08-01 2015-05-01 We describe herein a new method that allows selective production of Catellani–Heck isomers from various aryl halides, including ones without ortho -groups. Under previous conditions, unhindered aryl halides were plagued with the formation of simple Heck isomers and multiple arylation and norbornene insertion.