C–H functionalization of tertiary amines by cross dehydrogenative coupling reactions: solvent-free synthesis of α-aminonitriles and β-nitroamines under aerobic condition

Abstract

A solvent-free synthesis of α-aminonitriles and β-nitroamines by oxidative cross-dehydrogenative coupling under aerobic condition is reported. A catalytic amount of molybdenum(vi) acetylacetonoate was found to catalyze cyanation of tertiary amines to form α-aminonitriles, whereas vanadium pentoxide was found to promote aza-Henry reaction to furnish β-nitroamines. Both of these environmentally benign reactions are performed in the absence of solvents using molecular oxygen as an oxidant.

PEGylated magnetic nanoparticles (PEG@Fe 3 O 4 ) as cost effective alternative for oxidative cyanation of tertiary amines via C H activation

“…Further, these bi-functional organic compounds having adjacent functional groups show dual reactivity as the nucleophilic addition provides an easy access to various compounds such as ␣-amino aldehydes, ketones and ␤-amino alcohols [20][21][22][23][24][25]. So far a number of metal-based catalysts, such as Fe [26][27][28], Ru [29,30], V [31], Mo [32], Au [33] and Re [34] in the presence of oxidants such as molecular oxygen, hydrogen peroxide, tert-butyl hydroperoxide (TBHP) have been reported for the direct oxidative cyanation of tertiary amines. Photoredox catalysts mainly based on ruthenium have also been reported for the oxidative ␣-cyanation of sp 3 C H bonds of tertiary amines [35][36][37][38].…”

Rhenium‐Catalyzed Oxidative Cyanation of Tertiary Amines with TMSCN

“…[1] The direct utilization of C-H bonds offers a number of advantages from both environmental and economical viewpoints as prefunctionalization of the substrates is not required and the synthetic procedures are generally shorter. [4] Several examples of metal-based catalysts, such as Ru, [5] Fe, [6] V, [7] and Mo, [8] in the presence of oxidants for the direct oxidative cyanation of tertiary amines have been reported. [2,3] Recently, the direct oxidative cyanation of C-H bonds adjacent to nitrogen atoms has attracted much interest, as bifunctional organic compounds with adjacent functional groups are highly useful and versatile intermediates in organic synthesis; moreover, these compounds have been widely used in the construction of biologically active natural products, such as alkaloids and vicinal diamines.…”

Direct oxidative cyanation of tertiary amines promoted by in situ generated hypervalent iodine(III)-CN intermediate

“…With PIFA, increasing the time of preactivation and shorten the reaction time led to the same yield (entry 5 vs entry 2). In order to alleviate the side reaction resulted from high temperature under strongly oxidative conditions, the temperature was lowered, which as a result, delivered the same level of reactivity (entries [6][7]. It is also observed that during the reaction, unreacted substrate was not detected by TLC due to the interaction with CF 3 COOH released from PIFA.…”