Cu(II)-catalysis in the reduction of , -dibenzoylhydroxylamine by a tertiary amine

Poly(ε-caprolactone)-block-polysarcosine by Ring-Opening Polymerization of Sarcosine N-Thiocarboxyanhydride: Synthesis and Thermoresponsive Self-Assembly

“…In previous works we showed that NTA was a promising monomer that could be synthesized easily and be kept stable for a longer time than NCA. The polymerization of NTA with high yields, high MWs and low PDIs was achieved with appropriate initiators and conditions. , Herein, ROP of sarcosine NTA was for the first time initiated by oxyamino-ended PCLs, and this initiator endowed the copolymer with a cleavable N–O bond between PSar and PCL blocks (e.g., cleavage under reduction by Pd-catalyzed hydrogenolysis or in acidic environment). − Di- and triblock copolymers, PSar- b -PCL and PSar- b -PCL- b -PSar, with different MWs and hydrophilic/hydrophobic ratios were obtained (see Table , CS1–10). Typical characterization results (NMR and SEC) are shown in Figures and for CS10 and its macroinitiator PCL5.…”

Reaction of Dioxazolones with Boronic Acids: Copper-Mediated Synthesis of N-Aryl Amides via N-Acyl Nitrenes

“…As shown in Scheme 4a, the desired product is mainly obtained within 1.5 h. Because benzamide 5a, possibly obtained from the reduction of 1a, might be a reactive intermediate, the anticipated Chan− Lam−Evans reaction at 1.5 and 18 h under standard reaction conditions was tested (Scheme 4b). 19 A short reaction time resulted in 3a with a yield of 18%, and similarly, a prolonged reaction time also afforded the product with a low yield. Based on these experiments, the formation of the desired N-phenyl amide product 3a was primarily attributed to the reaction of dioxazolone 1a, instead of benzamide 5a, which resulted in the amide product with a higher yield (Scheme 4a and 4b).…”

“…Therefore, several mechanistic experiments were conducted to clarify the reaction pathway underlying this transformation. As shown in Scheme a, the desired product is mainly obtained within 1.5 h. Because benzamide 5a , possibly obtained from the reduction of 1a , might be a reactive intermediate, the anticipated Chan–Lam–Evans reaction at 1.5 and 18 h under standard reaction conditions was tested (Scheme b) . A short reaction time resulted in 3a with a yield of 18%, and similarly, a prolonged reaction time also afforded the product with a low yield.…”

Copper-catalyzed synthesis of primary amides through reductive N–O cleavage of dioxazolones

“…More recently, organic photocatalytic systems have proven effective in cleaving N–O bonds through a single-electron transfer process, avoiding the use of stoichiometric reductants under mild conditions. 34 In addition, O -acylated hydroxamic acids bearing weak N–O bonds (45 kcal mol −1 ) were effectively converted to primary amides by copper( ii ) salts 35 and ruthenium catalysts. 36 Moreover, a recent study showcased hydroxamic acids as amide sources, easily synthesized from carboxylic acids and hydroxylamine using 1,1′-carbonyldiimidazole, would be reduced to corresponding primary amides using thioacetic acid, NH 4 HCO 3 in ethanol.…”