754-10-9Relevant articles and documents
Time-Resolved Crystallography of the Reaction Intermediate of Nitrile Hydratase: Revealing a Role for the Cysteinesulfenic Acid Ligand as a Catalytic Nucleophile
Yamanaka, Yasuaki,Kato, Yuki,Hashimoto, Koichi,Iida, Keisuke,Nagasawa, Kazuo,Nakayama, Hiroshi,Dohmae, Naoshi,Noguchi, Keiichi,Noguchi, Takumi,Yohda, Masafumi,Odaka, Masafumi
, p. 10763 - 10767 (2015)
The reaction mechanism of nitrile hydratase (NHase) was investigated using time-resolved crystallography of the mutant NHase, in which βArg56, strictly conserved and hydrogen bonded to the two post-translationally oxidized cysteine ligands, was replaced by lysine, and pivalonitrile was the substrate. The crystal structures of the reaction intermediates were determined at high resolution (1.2-1.3?). In combination with FTIR analyses of NHase following hydration in H218O, we propose that the metal-coordinated substrate is nucleophilically attacked by the O(SO-) atom of αCys114-SO-, followed by nucleophilic attack of the S(SO-) atom by a βArg56-activated water molecule to release the product amide and regenerate αCys114-SO-.
Ru(ii)- And Ru(iv)-dmso complexes catalyze efficient and selective aqueous-phase nitrile hydration reactions under mild conditions
Dubey, Santosh Kumar,Kaur, Gurmeet,Rath, Nigam P.,Trivedi, Manoj
, p. 17339 - 17346 (2021/10/08)
New water-soluble ruthenium(ii)- and ruthenium(iv)-dmso complexes [RuCl2(dmso)2(NH3)(CH3CN)] (1), [RuCl2(dmso)3(CH3CN)] (2), and [RuCl2(dmso)3(NH3)]·PF6·Cl (3) have been synthesized and characterized using elemental analyses, IR, 1H and 31P NMR, and electronic absorption spectroscopy. The molecular structures of complexes 1-3 were determined crystallographically. The reactivity of complexes 1-3 has been tested for aqueous-phase nitrile hydration at 60 °C in air, and good efficiency and selectivity are shown for the corresponding amide derivatives. Best performance is achieved with complex 3. Amide conversions of 56-99% were obtained with a variety of aromatic, alkyl, and vinyl nitriles. The reaction tolerated hydroxyl, nitro, bromo, formyl, pyridyl, benzyl, alkyl, and olefinic functional groups. Amides were isolated by simple decantation from the aqueous-phase catalyst. A catalyst loading down to 0.0001 mol% was examined and turnover numbers as high as 990?000 were observed. The catalyst was stable for weeks in solution and could be reused more than seven times without significant loss in catalytic activity. The gram-scale reaction was also performed to produce the desired product in high yields. This journal is
Ring Opening/Site Selective Cleavage in N-Acyl Glutarimide to Synthesize Primary Amides
Govindan, Karthick,Lin, Wei-Yu
supporting information, p. 1600 - 1605 (2021/03/03)
A LiOH-promoted hydrolysis selective C-N cleavage of twisted N-acyl glutarimide for the synthesis of primary amides under mild conditions has been developed. The reaction is triggered by a ring opening of glutarimide followed by C-N cleavage to afford primary amides using 2 equiv of LiOH as the base at room temperature. The efficacy of the reactions was considered and administrated for various aryl and alkyl substituents in good yield with high selectivity. Moreover, gram-scale synthesis of primary amides using a continuous flow method was achieved. It is noted that our new methodology can apply under both batch and flow conditions for synthetic and industrial applications.