Primary amides: Sustainable weakly coordinating groups in transition metal-catalyzed C–H bond functionalization reactions

Precise control of the site selectivity in ruthenium-catalyzed C–H bond amidations using cyclic amides as powerful directing groups

“…16 This study also shows the subtlety associated with C–H bond amidations because in the present case ruthenium outperforms cobalt as a catalyst and dioxazolone outperforms tosylazide as an amidating agent, respectively, which is somehow unexpected with regard to precedents in the literature. 6–13,28 Moreover, this contribution establishes that cyclic amides are more powerful directing groups than acyclic ones or other coordinating groups such as imides and pyridines, at least for ruthenium-catalyzed C–H bond amidations. In addition, we provide the first mechanistic considerations of ruthenium-catalyzed C–H bond aminations supported by in-depth DFT calculations.…”

“…Among many known C–N bond-forming reactions, transition metal-catalyzed ortho -C–H amidation ones are particularly interesting given the ubiquitous nature of amide bonds. 9,10 Catalysts based on Ir, Rh, Pd, Ru or Co are of choice due to their high reactivity 11 and amidating agents derived from dioxazolone are preferred instead of azides because of their benchmark stability. 12 Taking this into account, it appears that all reports from the literature dealing with transition metal-catalyzed C–H bond amidations focused exclusively on substrates containing only one aromatic C–H bond available for reaction (Scheme 1).…”

Acceptorless dehydrogenative synthesis of primary amides from alcohols and ammonia

“…Primary amides feature extensively in organic synthesis, and their ubiquity in pharmaceuticals, natural products, agrochemicals and biologically-active molecules has made their preparation the focus of widespread attention. 5 Classical synthetic methodologies involve the amidation of carboxylic acid derivatives or hydration of nitriles – processes that either generate considerable waste or require the use of pre-prepared starting materials. 6 Consequently, there is high demand for more sustainable and efficient means of accessing primary amides from readily-available sources.…”

Orthogonal Arylation of a Diene‐Sulfonamide Using Cationic Transition Metal Catalysts

“…Given the particular importance of the sulfonamide group for medicinal chemistry issues, we strove to close this gap and found that a catalyst system originally introduced by the groups of Ackermann [28] and Jeganmohan [29] that consists of [RuCl 2 (p-cymene)] 2 , Cu(OAc) 2 • H 2 O and AgSbF 6 also enables the oxidative ortho-alkenylation of acetanilides with the tertiary ethene sulfonamide mentioned above. [17] A survey of reviews [30][31][32][33][34][35][36][37][38][39] and original literature [40][41][42][43][44][45] on Ru-catalyzed CÀ Hactivating alkenylations reveals that mostly "activated", i.e. electron deficient olefins, in particular acrylates are used in these alkenylations.…”