- Ru-based complexes as heterogeneous potential catalysts for the amidation of aldehydes and nitriles in neat water
-
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).
- Arafa, Wael Abdelgayed Ahmed
-
supporting information
p. 1056 - 1064
(2020/11/09)
-
- Transfer Hydration of Dinitriles to Dicarboxamides
-
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.
- Naka, Hiroshi,Naraoka, Asuka
-
supporting information
p. 1977 - 1980
(2019/10/22)
-
- Modulation of Nitrile Hydratase Regioselectivity towards Dinitriles by Tailoring the Substrate Binding Pocket Residues
-
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.
- Cheng, Zhongyi,Cui, Wenjing,Xia, Yuanyuan,Peplowski, Lukasz,Kobayashi, Michihiko,Zhou, Zhemin
-
p. 449 - 458
(2017/12/15)
-
- Synthesis method for doxepin drug intermediate phthalic diamide
-
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.
- -
-
Paragraph 0014; 0015
(2016/12/01)
-
- Copper-Catalyzed Formal [4 + 1] Cycloaddition of Benzamides and Isonitriles via Directed C-H Cleavage
-
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.
- Takamatsu, Kazutaka,Hirano, Koji,Miura, Masahiro
-
p. 4066 - 4069
(2015/09/01)
-
- The structures of several modified isoindolines, the building blocks of phthalocyanines
-
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.
- Engle, James T.,Allison, Ashley N.,Standard, Joshua M.,Tamgho, Ingrid-Suzy,Ziegler, Christopher J.
-
p. 712 - 721
(2013/09/24)
-
- Ruthenium-catalyzed one-pot synthesis of primary amides from aldehydes in water
-
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.
- Garcia-Alvarez, Rocio,Diaz-Alvarez, Alba E.,Crochet, Pascale,Cadierno, Victorio
-
p. 5889 - 5894
(2013/05/09)
-
- A general and efficient heterogeneous gold-catalyzed hydration of nitriles in neat water under mild atmospheric conditions
-
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
- 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)
-
- Chemistry by nanocatalysis: First example of a solid-supported RAPTA complex for organic reactions in aqueous medium
-
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.
- García-Garrido, Sergio E.,Francos, Javier,Cadierno, Victorio,Basset, Jean-Marie,Polshettiwar, Vivek
-
experimental part
p. 104 - 111
(2012/01/06)
-
- Photocatalytic behaviour of tantalum (V) phthalocyanines in the presence of gold nanoparticles towards the oxidation of cyclohexene
-
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%.
- Chauke, Vongani P.,Antunes, Edith,Chidawanyika, Wadzanai,Nyokong, Tebello
-
scheme or table
p. 121 - 128
(2011/03/22)
-
- Synthesis of oligodeoxynucleotides using fully protected Deoxynucleoside 3c-Phosphoramidite building blocks and base recognition of Oligodeoxynucleotides incorporating N3-Cyano-Ethylthymine
-
Oligodeoxynucleotide (ODN) synthesis, which avoids the formation of side products, is of great importance to biochemistry-based technology development. One side reaction of ODN synthesis is the cyanoethylation of the nucleobases. We suppressed this reaction by synthesizing ODNs using fully protected deoxynucleoside 3c-phosphoramidite building blocks, where the remaining reactive nucleobase residues were completely protected with acyl-, diacyl-, and acyl-oxyethylene-type groups. The detailed analysis of cyanoethylation at the nucleobase site showed that N3-protection of the thymine base efficiently suppressed the Michael addition of acrylonitrile. An ODN incorporating N3-cyanoethylthymine was synthesized using the phosphoramidite method, and primer extension reactions involving this ODN template were examined. As a result, the modified thymine produced has been proven to serve as a chain terminator.
- Tsunoda, Hirosuke,Kudo, Tomomi,Ohkubo, Akihiro,Seio, Kohji,Sekine, Mitsuo
-
experimental part
p. 7509 - 7531
(2011/02/28)
-
- PREPARATION METHOD FOR PHTHALAMIDE
-
PROBLEM TO BE SOLVED: To provide a method by which a phthalamide can be prepared from a phthalimide with a high yield and with good operability. SOLUTION: The phthalamide is prepared by reacting a phthalimide such as one represented by formula (1) (wherein R is hydrogen, a halogen, or an optionally substituted alkyl group) with ammonia without substantially allowing an organic solvent and water to be present in the reaction system. Preferably, ammonia used is liquid ammonia, and the amount of it used is 10-120 mol per mol of the phthalimide. COPYRIGHT: (C)2006,JPOandNCIPI
- -
-
Page/Page column 4
(2008/06/13)
-
- Selective N-debenzylation of amides with p-TsOH
-
N-Benzylamides were debenzylated efficiently with 4 equiv. of p-TsOH in refluxing toluene. Good to quantitative yields of the desired primary amides were obtained within 2-4 h from a wide variety of N-2,4-dimethoxybenzylamides. N-4-Methoxylbenzyl amides and N-benzylamides were also debenzylated cleanly. In the case of N-2,4-dimethoxylbenzylamides, selective N-debenzylation was possible in the presence of N-Fmoc, N-t-BOC or N-trityl-protection. Protected amino acid amides survived these conditions without any detectable epimerization.
- Chern, Ching-Yuh,Huang, Yu-Ping,Kan, Wai Ming
-
p. 1039 - 1041
(2007/10/03)
-
- 2-piperazinoalkylaminobenzo-azole derivatives: dopamine receptor subtype specific ligands
-
Disclosed are compounds of the formula: or pharmaceutically acceptable salts thereof, wherein: A is (un)substituted alkylene; R1and R2are the same or different and represent hydrogen, halogen, alkyl, alkoxy, alkylthio, hydroxy, (un)substitutedamino, cyano, nitro, sulfonamide, trifluoromethyl or trifluoromethoxy; R3, R4, R5, R6, and R8are independently hydrogen or alkyl; and X is sulfur, oxygen or NR7where R8is defined herein; m is an integer chosen from 0, 1 or 2; and Ar is an aryl or heteroaryl group as further defined herein, which compounds are useful for the treatment and/or prevention of neuropsychological disorders including, but not limited to, schizophrenia, mania, dementia, depression, anxiety, compulsive behavior, substance abuse, Parkinson-like motor disorders and motion disorders related to the use of neuroleptic agents.
- -
-
-
- 2-AMINO-BENZOXAZINONES FOR THE TREATMENT OF VIRAL INFECTIONS
-
A class of compounds for the treatment of viral infections. Compounds of particular interest are defined by Formula II STR1 wherein R 28 is selected from (a) amino substituted with one or two radicals selected from alkyl, aralkyl, heterocycoalkyl, heterocyclo, and aryl, and (b) amino acid residues and derivatives thereof; wherein R 29 is selected from hydrido, alkyl, halo, STR2 wherein R 30 is selected from alkyl, alkoxy, alkylamino, carboxyalkyl, alkoxyalkyl, alkylaminoalkyl, cycloalkyl, heterocyclo, heterocycloalkyl, heterocycloalkoxy, alkylaminoalkoxy, alkylaminoalkylamino, heterocycloalkylamino, and N-aralkylamino; wherein R 31 is alkyl; wherein R 32 is alkyl and aryl; or a pharmaceutically-acceptable salt thereof.
- -
-
-
- AMMONOLYSIS OF CYCLIC IMIDES OF AROMATIC ACIDS
-
In cyclic imides of aromatic di-and tetracarboxylic acids ammonolysis with the opening of the ring goes readily in water, but it does not go in anhydrous aprotic solvents.Quantum-chemical calculations of model compounds by the MINDO/3 method suggest the possibility of activation in an aqueous-alkaline medium as a result of the tautomeric transformation of the imide into the imidol, which has higher electrophilic reactivity.Here the transfer of a proton goes as a two-stage process on account of the successive participation of anions and molecules of water in the reaction.
- Arkhipova, i. A.,Gabdrakipov, V. Z.,Shalabaeva, I. D.,Zhubanov, B. A.
-
p. 535 - 540
(2007/10/02)
-
- Kinetic and equilibrium in the ammonolysis of substituted phthalimides
-
Kinetic studies are reported for the base hydrolysis to phthalamic acid anions (H) and ammonolysis to phthalamides (A) for seven phthalimides (P): 1, unsubstituted; 2, 4-NO2; 3, 4-Cl; 4, 4-tBu; 5, 3-NO2; 6, 3-Me; 7, 3-Me3Si.The hydrolysis kinetics require two mechanisms, one which is first order in neutral imide and first order in hydroxide ion, and a second, which is important only in quite concentrated NaOH, which is first order in neutral phthalimide and second order in hydroxide ion.Ammonolysis kinetics for 1-5 revealed the rate law: Rate = kN ->.A mechanism is proposed with rate-determining breakdown of the anionic form of the tetrahedral intermediate derived by addition of NH3 to the phthalimide.The ammonolysis is reversible.The phthalamide hydrolyzes to the phthalamic acid via cyclization to an intermediate phthalimide, which is detected in concentrated base where its formation from phthalamide is more rapid than its subsequent hydrolysis.Rate constants for the cyclization follow the rate law: Rate = kcyc ->.This reaction is the microscopic reverse of the ammonolysis, and the ratio kN/kcyc provides the equilibrium constant Keq for the reaction P + NH3 = A.Values for 1-5 lie in the range 2 x 102 - 4 x 103.With 3-methylphthalimide, kinetics in aqueous ammonia do not obey a first-order relationship, but they could be analyzed by a scheme whereby the phthalimide is converted reversibly to the phthalamide and simultaneously undergoes an irreversible hydrolysis.The value of Keq in the system is 1.8.With 3-trimethylsilylphthalimide the value of Keq is further reduced to 0.01.The ammonolysis reaction does occur more quickly than hydrolysis but the equilibrium is so unfavorable that even in concentrated ammonia only a small amount of the phthalamide is ever formed.
- McClelland, Robert A.,Seaman, N. Esther,Duff, James M.,Branston, R. E.
-
p. 121 - 128
(2007/10/02)
-
