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One-pot multi-step procedures bear the potential to rapidly build up molecular complexity while avoiding the wasteful and costly isolations and purifications of consecutive intermediates. Here we report multi-catalytic protocols that convert alkenes, unsaturated aliphatic alcohols, and aryl boronic acids into secondary benzylic alcohols with high stereoselectivities under sequential catalysis that integrates alkene cross-metathesis, isomerization, and nucleophilic addition. Because each transformation of the sequence is executed by an independent catalyst, without any catalytic cross-reactivity, allylic alcohols bearing a prochiral double bond can be converted to any stereoisomer of the product with high stereoselectivity (>98:2 er and >20:1 dr). Overall, with the aid of up to four catalysts operating in a single vessel, the protocols directly convert simple starting materials into a range of value-added products with high stereocontrol and excellent material efficiency, demonstrating both the efficacy and the advantages of the one-pot synthesis employing multiple transition-metal catalysts.

A practical homogeneous and gas‐liquid palladium‐catalyzed Catellani‐type reaction using a continuous‐flow platform is described. The implementation of continuous‐flow technology allowed the acceleration of the transformation and, for the first time, expansion of the chemical space to gaseous olefins (i.e., ethylene, propylene and 3,3,3‐trifluoropropene), thus providing a safe and practical approach to sterically hindered ortho‐disubstituted styrenes and vinyl arenes. The complete control over the stoichiometry of gaseous reagents through flow technology proved essential for directing the selectivity of the Catellani reaction to the desired products.

Asymmetric transition-metal catalysis represents a fascinating challenge in the field of organic chemistry research. Since seminal advances in the late 60s, which were finally recognized by the Nobel Prize to Noyori, Sharpless and Knowles in 2001, the scientific community explored several approaches to emulate nature in producing chiral organic molecules. In a scenario that has been for a long time dominated by the use of late-transition metals (TM) catalysts, the use of 3d-TMs and particularly iron has found, recently, a widespread application. Indeed, the low toxicity and the earth-abundancy of iron, along with its chemical versatility, allowed for the development of unprecedented and more sustainable catalytic transformations. While several competent reviews tried to provide a complete picture of the astounding advances achieved in this area, within this review we aimed to survey the latest achievements and new concepts brought in the field of enantioselective iron-catalyzed transformations.

Dihydrodibenzo [b,f]azepines and dibenzo [b,f]azepines can be efficiently synthesized from aryl bromides, o-bromoanilines and norbornene or norbornadiene by means of palladium catalysis. This protocol gives access to dibenzo[b,f]azepine core containing a variety of electron-withdrawing substituents on both aromatic rings and complements the previously reported methodology where electron rich aryl iodides were preferentially used. The presence of KI, even in sub-stoichiometric amount, is crucial for this three-component reaction. The proper addition of iodide anions has a dramatic effect on reaction rate and selectivity. A formal three-step synthesis of the tricyclic antidepressant Clomipramine (Anafranil ) is also described.

A variety of isocoumarins have been synthesized directly from 2-halobenzoates and ketones through a palladium-catalyzed α-arylation step followed by an intramolecular cyclization process. The addition of iodide anions to the reaction mixture increased yields and selectivities especially when 2-bromobenzoates were employed. This phosphine-free one-pot synthesis features a high functional group tolerance and gives access to richly decorated isocoumarins. This general methodology was successful in the total synthesis of Xyridin A, an important natural product with antibacterial and antifungal activity.

2-Imidazolidinone and its analogues are omnipresent structural motifs of pharmaceuticals, natural products, chiral auxiliaries, and intermediates in organic syntheses. Over the years, continuous efforts have been addressed to the development of sustainable and more efficient protocols for the synthesis of these heterocycles. This review gives a summary of the catalytic strategies to access imidazolidin-2-ones and benzimidazolidin-2-ones that have appeared in the literature from 2010 to 2018. Particularly important contributions beyond the timespan will be mentioned. The review is organized in four main chapters that identify the most common approaches to imidazolidin-2-one derivatives: (1) the direct incorporation of the carbonyl group into 1,2-diamines, (2) the diamination of olefins, (3) the intramolecular hydroamination of linear urea derivatives and (4) aziridine ring expansion. Methods not included in this classification will be addressed in the miscellaneous section.