88-96-0Relevant academic research and scientific papers
Ru-based complexes as heterogeneous potential catalysts for the amidation of aldehydes and nitriles in neat water
Arafa, Wael Abdelgayed Ahmed
supporting information, p. 1056 - 1064 (2020/11/09)
Five novel heterogeneous mononuclear complex-anchored Ru(III) have been efficiently sono-synthesized and characterized by utilizing several analytical techniques. The assembled complexes could be utilized as effective, robust and recyclable (up to eight consecutive runs) catalysts for one-pot transformation of a vast array of nitriles and aldehydes to primary amides in H2O under aerobic conditions. Moreover, some unreported di- and tetra-amide derivatives were obtained also under the optimal conditions. The results of ICP/OES analysis demonstrated that there is no detected leaching of the recycled catalyst, which suggests the real heterogeneity of the present protocol. The present Ru-complexes exhibited superiority compared to other reported catalysts for amide preparation in terms of low catalyst load, short reaction time, low operating temperature, no hazardous additives required, and high values of TON (990) and TOF (1980 h11).
Transfer Hydration of Dinitriles to Dicarboxamides
Naka, Hiroshi,Naraoka, Asuka
supporting information, p. 1977 - 1980 (2019/10/22)
We present a robust method for double transfer hydration of dinitriles to afford diamides. The transfer hydration of 1, n -dinitriles (n = 1-6) proceeds smoothly in the presence of a palladium(II) catalyst with acetamide as a water donor, affording the corresponding diamides in moderate to high yields, without involving significant side reactions such as monohydration or cyclization. The equilibrium was shifted in the forward direction by removing coproduced acetonitrile under reduced pressure.
Modulation of Nitrile Hydratase Regioselectivity towards Dinitriles by Tailoring the Substrate Binding Pocket Residues
Cheng, Zhongyi,Cui, Wenjing,Xia, Yuanyuan,Peplowski, Lukasz,Kobayashi, Michihiko,Zhou, Zhemin
, p. 449 - 458 (2017/12/15)
The regioselective hydration of dinitriles is one of the most attractive approaches to prepare ω-cyanocarboxamides or diamides and such regioselectivity is often beyond the capability of chemical catalysts. The use of nitrile hydratase to biotransform dinitriles selectively would be highly desirable. Molecular docking of two aliphatic dinitriles and two aromatic dinitriles into the active site of a nitrile hydratase (NHase) from Rhodococcus rhodochrous J1 allowed the identification of proximal NHase substrate binding pocket residues. Four residues (βLeu48, βPhe51, βTyr68, and βTrp72) were selected for single- and double-point mutations to modulate the NHase regioselectivity towards dinitriles. Several NHase mutants with an altered regioselectivity were obtained, and the best one was Y68T/W72Y. Docking experiments further indicated that the poor binding affinity of aliphatic and aromatic ω-cyanocarboxamides to the NHase variants resulted in distinct regioselectivity between wild-type and mutated NHases.
Synthesis method for doxepin drug intermediate phthalic diamide
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Paragraph 0014; 0015, (2016/12/01)
The invention provides a synthesis method for doxepin drug intermediate phthalic diamide. The synthesis method includes the following steps that 2.3 mol of phthalic anhydride solution, 300 ml of cyclohexane, 2.6-2.9 mol of 2-hydroxyl-benzamide solution are added to a reaction container provided with a stirrer, a thermometer and a dropping funnel, the stirring speed is controlled to be 130-170 rpm, the temperature of the solution is raised to 60-65 DEG C, a reaction is conducted for 3-5 h, solids are separated out after cooling, an intermediate is obtained and added to 600 ml of 2-nitro-hypochlorous acid phenyl ester solution, the temperature of the solution is raised to 70-75 DEG C, the reaction is conducted for 90-130 min, the temperature of the solution is reduced to 10-15 DEG C, solids are separated out, filtering is conducted, saline solution washing, hexane washing, dimethylamine washing and reduced pressure distillation are conducted, 100-106 DEG C cut fractions are collected, recrystallization is conducted in ethyl acetate, and the crystal of phthalic diamide is obtained.
Copper-Catalyzed Formal [4 + 1] Cycloaddition of Benzamides and Isonitriles via Directed C-H Cleavage
Takamatsu, Kazutaka,Hirano, Koji,Miura, Masahiro
, p. 4066 - 4069 (2015/09/01)
A copper-catalyzed formal [4 + 1] cycloaddition of benzamides and isonitriles via 8-aminoquinoline-directed C-H cleavage has been developed. The reaction proceeds well even in the presence of a base metal catalyst, CuBr·SMe2, alone to deliver the corresponding 3-iminoisoindolinones in good yields. Moreover, the unique acceleration effects of diphenyl sulfide are also disclosed.
Ruthenium-catalyzed one-pot synthesis of primary amides from aldehydes in water
Garcia-Alvarez, Rocio,Diaz-Alvarez, Alba E.,Crochet, Pascale,Cadierno, Victorio
, p. 5889 - 5894 (2013/05/09)
The readily available arene-ruthenium(ii) complex [RuCl2(η 6-C6Me6){P(NMe2)3}] (5 mol%) proved to be an efficient catalyst for the direct synthesis of primary amides from aldehydes and hydroxylamine hydrochloride (NH2OH· HCl) in water at 100 °C. The process, which requires the presence of NaHCO3 to catch the HCl released during the formation of the key aldoxime intermediates, was operative with both aromatic, heteroaromatic, α,β-unsaturated and aliphatic aldehydes, and tolerated several functional groups. A greener approach using commercially available NH 2OH solution (50 wt.% in water) is also presented.
The structures of several modified isoindolines, the building blocks of phthalocyanines
Engle, James T.,Allison, Ashley N.,Standard, Joshua M.,Tamgho, Ingrid-Suzy,Ziegler, Christopher J.
, p. 712 - 721 (2013/09/24)
This report presents the single crystal X-ray structures of several substituted isoindolines that have been frequently used as starting materials for phthalocyanines, phthalocyanine analogs and related chelates. The structures of 1,3-diiminoisoindoline (1), 1,3-bis(hydroxyimino)isoindoline (2), 1,4-diaminophthalazine (3), 1,1,3-trichloroisoindoline (4) and 3-imino-1-oxoisoindoline (5) are reported; compounds 2 and 3 are synthesized from diiminoisoindoline (1) and 4 and 5 are produced from phthalimide. All five compounds are planar macrocycles, and localization of double bonds can be readily determined. We elucidated one of the known structures of 1 at low temperature, and observed two additional new structures of 1. For the crystal forms of 1 and compounds 2, 3, and 5, hydrogen bonding in the solid state was observed. Compounds 1, 2 and 3 form extended hydrogen bonded arrays in the solid state, whereas 5 forms discrete hydrogen bonded dimers.
A general and efficient heterogeneous gold-catalyzed hydration of nitriles in neat water under mild atmospheric conditions
Liu, Yong-Mei,He, Lin,Wang, Miao-Miao,Cao, Yong,He, He-Yong,Fan, Kang-Nian
scheme or table, p. 1392 - 1396 (2012/10/07)
Mild, efficient and general: Titania decorated with nanometer-sized gold particles acts as an efficient catalyst for the selective hydration of a wide range of chemically diverse nitriles into valuable amides in neutral water, under mild atmospheric conditions (see image). The process shows promise for a facile and direct one-pot synthesis of ?μ-caprolactam, an industrially important molecule, starting from 6-aminocapronitrile. Copyright
Chemistry by nanocatalysis: First example of a solid-supported RAPTA complex for organic reactions in aqueous medium
García-Garrido, Sergio E.,Francos, Javier,Cadierno, Victorio,Basset, Jean-Marie,Polshettiwar, Vivek
experimental part, p. 104 - 111 (2012/01/06)
A ruthenium-arene-PTA (RAPTA) complex has been supported for the first time on an inorganic solid, that is, silica-coated ferrite nanoparticles. The resulting magnetic material proved to be a general, very efficient and easily reusable catalyst for three synthetically useful organic transformations; selective nitrile hydration, redox isomerization of allylic alcohols, and heteroannulation of (Z)-enynols. The use of low metal concentration, environmentally friendly water as a reaction medium, with no use at all of organic solvent during or after the reactions, and microwaves as an alternative energy source renders the synthetic processes reported herein "truly" green and sustainable. RAPTA's delight: A nano-RAPTA complex supported on silica-coated ferrite nanoparticles proved to be a general, very efficient and easily reusable catalyst for three synthetically useful organic transformations; selective nitrile hydration, redox isomerization of allylic alcohols, and heteroannulation of (Z)-enynols. The use of low metal concentrations, water as a reaction medium, and microwaves as an energy source renders these processes green and sustainable.
Photocatalytic behaviour of tantalum (V) phthalocyanines in the presence of gold nanoparticles towards the oxidation of cyclohexene
Chauke, Vongani P.,Antunes, Edith,Chidawanyika, Wadzanai,Nyokong, Tebello
scheme or table, p. 121 - 128 (2011/03/22)
This paper presents the photocatalytic oxidation of cyclohexene using (OH)3TaPc derivatives in the absence or presence of gold nanoparticles (AuNPs). The photochemical parameters that include photodegradation (ΦP) and singlet oxygen (Φ Δ) quantum yields are also reported in this work. The ΦΔ values were 0.47 and 0.36 for complexes 1a and 1b, respectively. The ΦΔ values improved drastically in the presence of AuNPs to 0.75 and 0.88, respectively. The ΦP values ranged from 1.02 to 2.45 × 10-6, showing stability of TaPc derivatives in the absence and presence of AuNPs. The photocatalytic products identified using gas chromatograph (GC) are cyclohexene oxide, 2-cyclohexen-1-ol, 2-cyclohexene-1-one and 1,2-cyclohexanediol. The percentage conversion values were higher in the presence of AuNPs. Singlet oxygen was determined to be the main agent involved in the photocatalytic oxidation of cyclohexene. The product yield percentage values for both TaPc complexes (1a and 1b) and TaPc in the presence of AuNPs ranged from 6.3 to 21.2%.
