- An aerobic oxidation of alcohols into carbonyl synthons using bipyridyl-cinchona based palladium catalyst
-
We have reported an aerobic oxidation of primary and secondary alcohols to respective aldehydes and ketones using a bipyridyl-cinchona alkaloid based palladium catalytic system (PdAc-5) using oxygen at moderate pressure. ThePdAc-5catalyst was analysed using SEM, EDAX, and XPS analysis. The above catalytic system is used in experiments for different oxidation systems which include different solvents, additives, and bases which are cheap, robust, non-toxic, and commercially available on the industrial bench. The obtained products are quite appreciable in both yield and selectivity (70-85%). In addition, numerous important studies, such as comparisons with various commercial catalysts, solvent systems, mixture of solvents, and catalyst mole%, were conducted usingPdAc-5. The synthetic strategy of oxidation of alcohol into carbonyl compounds was well established and all the products were analysed using1H NMR,13CNMR and GC-mass analyses.
- Cheedarala, Ravi Kumar,Chidambaram, Ramasamy R.,Siva, Ayyanar,Song, Jung Il
-
p. 32942 - 32954
(2021/12/02)
-
- Visible light mediated selective oxidation of alcohols and oxidative dehydrogenation of N-heterocycles using scalable and reusable La-doped NiWO4nanoparticles
-
Visible light-mediated selective and efficient oxidation of various primary/secondary benzyl alcohols to aldehydes/ketones and oxidative dehydrogenation (ODH) of partially saturated heterocycles using a scalable and reusable heterogeneous photoredox catalyst in aqueous medium are described. A systematic study led to a selective synthesis of aldehydes under an argon atmosphere while the ODH of partially saturated heterocycles under an oxygen atmosphere resulted in very good to excellent yields. The methodology is atom economical and exhibits excellent tolerance towards various functional groups, and broad substrate scope. Furthermore, a one-pot procedure was developed for the sequential oxidation of benzyl alcohols and heteroaryl carbinols followed by the Pictet-Spengler cyclization and then aromatization to obtain the β-carbolines in high isolated yields. This methodology was found to be suitable for scale up and reusability. To the best of our knowledge, this is the first report on the oxidation of structurally diverse aryl carbinols and ODH of partially saturated N-heterocycles using a recyclable and heterogeneous photoredox catalyst under environmentally friendly conditions.
- Abinaya, R.,Balasubramaniam, K. K.,Baskar, B.,Divya, P.,Mani Rahulan, K.,Rahman, Abdul,Sridhar, R.,Srinath, S.
-
p. 5990 - 6007
(2021/08/24)
-
- A process for preparing 2, 3 - dichloro-benzaldehyde (by machine translation)
-
The present invention provides a process for preparing 2, 3 - dichloro formaldehyde of the method, the method including: the 2, 3 - two chlorine animal pens fork two bromines solution, water and catalyst through the dynamic tubular reactor to carry out the hydrolysis reaction to obtain the 2, 3 - dichloro formaldehyde; the method of the invention, through the use of dynamic tubular reactor, using novel process route, hydrogen bromide as the hydrolysis catalyst, homogeneous phase hydrolysis the continuous preparation of 2, 3 - dichloro formaldehyde, compared with the traditional tank reactor and the like, has high mass transfer efficiency, good heat transfer efficiency, automatic precise control, high safety, shortens the reaction time, only needs 1 h can finish in about reaction, improves the reaction conversion and yield, is very suitable for industrial production. (by machine translation)
- -
-
Paragraph 0034-0066
(2019/11/20)
-
- Method for synthesizing felodipine intermediate 2,3-dichlorobenzaldehyde
-
The invention discloses a method for synthesizing felodipine intermediate 2,3-dichlorobenzaldehyde. The method comprises the following steps: performing sulfonating, hydroformylation and de-sulfonation on o-dichlorobenzene to generate 2,3-dichlorobenzaldehyde; under the condition of a protonic acid, performing protonation and fracturing on urotropine to generate imine ions; using the imine ions toundergo electrophilic aromatic substitution on an aromatic ring and undergo tautomerism to generate a benzylamine derivative; performing secondary protonation and fracturing on the rest of urotropineto generate imine ions, and performing an intramolecular redox reaction to partially oxidize the benzylamine into benzylidene imine ions; and performing hydrolysis to obtain an aldehyde. The method has high selectivity, less pollution discharge and lower cost.
- -
-
Paragraph 0030; 0036; 0037; 0043; 0044; 0051; 0052; 0053-007
(2019/10/01)
-
- Degradation of substituted phenols with different oxygen sources catalyzed by Co(II) and Cu(II) phthalocyanine complexes
-
Research on substituted phenol degradations has received substantial attention. In this work, effective Co(II) and Cu(II) phthalocyanine complexes as catalysts were studied to degrade toxic phenols to harmless products. The effect of various process parameters, such as initial concentration of phenol, catalyst, oxygen sources, and temperature on the degradation reaction was investigated to achieve maximum degradation efficiency. The catalytic activities of Co(II) and Cu(II) phthalocyanines were evaluated for oxidation of phenolic compounds such as p-nitrophenol, o-chlorophenol, 2,3-dichlorophenol, and m-methoxyphenol. Co(II) phthalocyanine displayed good catalytic performance in degradation of 2,3-dichlorophenol to 2,3-dichlorobenzaldehyde and 2,3-dichloro-1,4-benzoquinone with the highest TON and TOF values within 3 h at 50 °C. The fate of catalyst during the degradation process was followed by UV–Vis spectroscopy.
- Saka, Ece Tugba,Dügdü, Esra,ünver, Yasemin
-
p. 1119 - 1130
(2019/05/17)
-
- Method for preparing 2,3-dichlorobenzaldehyde through continuous oxidization of 2,3-dichlorotoluene
-
The invention relates to a method for preparing 2,3-dichlorobenzaldehyde through continuous oxidization of 2,3-dichlorotoluene, and belongs to the technical field of organic synthesis processes. The method comprises the following steps: taking 2,3-dichlorotoluene compound as a raw material, one or more metal ion complexes of cobalt, molybdenum and bromine is used as catalyst, hydrogen peroxide is used as an oxidizing agent, acetic acid is used as a solvent, and 2,3-dichlorotoluene is continuously oxidized in a tubular reactor to prepare the 2,3-dichlorobenzaldehyde. The method is mild in condition, short in reaction time and high in raw material utilization rate, effective control in the reaction process can be realized, safety and stability are achieved, continuous operation is achieved, and production efficiency is high.
- -
-
Paragraph 0039; 0040
(2017/07/12)
-
- Synthetic process of 2,3-dichlorobenzaldehyde
-
The invention discloses a synthetic process of 2,3-dichlorobenzaldehyde. The synthetic process comprises the steps that 2,3-dichlorotoluene is used as a raw material, bromine is used as an auxiliary material, azodiisobutyronitrile is used as a catalyst, the bromine utilization rate is improved through hydrogen peroxide, the generated 2,3-dichlorobenzyl bromide is hydrolyzed into 2,3-dichlorobenzaldehyde in 30 wt% of sodium carbonate water solution, the 2,3-dichlorobenzaldehyde is generated by using hydrogen bromide to catalyze hydrogen peroxide oxidization, the total yield is 70% or above, and the product purity is 99.25% or above. The raw material conversion rate and selectivity of the process are high. In addition, the by-product production rate is reduced, the bromine utilization rate is improved, the bromine usage amount is decreased, and the synthetic process is greener and environmentally friendly compared with a traditional metal-catalyzed oxidation technology.
- -
-
-
- Metal-free, visible-light photoredox catalysis: Transformation of arylmethyl bromides to alcohols and aldehydes
-
A mild, simple, and controllable metal-free photocatalytic system for the transformation of arylmethyl bromides to corresponding alcohols and aldehydes in high yields with visible-light irradiation has been achieved. Eosin Y was found to be an efficient promoter for this oxidative dehalogenation reaction under photo irradiation conditions.
- Li, Jian,Wang, Hongni,Liu, Li,Sun, Jiangtao
-
p. 49974 - 49978
(2014/12/10)
-
- Solvent-controlled copper-catalyzed oxidation of benzylic alcohols to aldehydes and esters
-
A procedure for the copper-catalyzed selective oxidation of primary alcohols to esters and aldehydes was developed. Under solvent-free conditions, self-oxidative esterification and cross-esterification of benzyl alcohols with various aliphatic alcohols proceed smoothly to give the corresponding esters in good yields. If DMF was used as a solvent, the benzyl alcohols were selectively converted into the corresponding aldehydes in excellent yields. Depend on solvent! Under solvent-free conditions, Cu-catalyzed oxidative self-esterification and cross-esterification of benzylic alcohols with various aliphatic alcohols proceed smoothly to give the corresponding esters in good yields. If DMF is used as a solvent, the benzylic alcohols are selectively converted into the corresponding aldehydes in excellent yields. DTBP = di-tert-butyl peroxide. Copyright
- Zhu, Yefeng,Wei, Yunyang
-
supporting information
p. 4503 - 4508
(2013/07/26)
-
- Heterocyclic dihydropyrimidine compounds
-
Novel heterocyclic dihydropyrimidine compounds useful as inhibitors of potassium channel function (especially inhibitors of the Kv1 subfamily of voltage gated K+ channels, especially inhibitors Kv1.5 which has been linked to the ultra-rapidly activating delayed rectifier K+ current IKur), methods of using such compounds in the prevention and treatment of arrhythmia and IKur-associated conditions, and pharmaceutical compositions containing such compounds.
- -
-
-
- Simple, economical and environmentally benign selective regeneration of carbonyl compounds from oximes and N,N-dimethyl hydrazones
-
A mild, efficient, selective method for the regeneration of carbonyl compounds from oximes and N,N-dimethylhydrazones in MeCN at ambient temperature or aqueous media has been carried out in excellent yields under K 5CoW12O40·3H2O (0.01 equiv) catalysis.
- Bose, D. Subhas,Reddy, A. V. Narsimha,Das, A. P. Rudra
-
p. 1883 - 1885
(2007/10/03)
-
- A convenient oxidative demasking of 1,3-dithiolanes and dithianes to carbonyl compounds with TBHP
-
Regeneration of carbonyl compounds from their 1,3-dithiolanes and dithianes was achieved using tert-butyl hydroperoxide (TBHP, aq. 70%) in high yields. Thus, an efficient, economical and experimentally simple protocol for dethioacetalization has been demonstrated.
- Barhate, Nivrutti B,Shinde, Popat D,Mahajan, Vishal A,Wakharkar, Radhika D
-
p. 6031 - 6033
(2007/10/03)
-
- Ferric chloride induced catalytic cleavage of oximes and hydrazones under solvent-free conditions
-
In an solvent-free system, oximes and hydrazones are rapidly transformed into parent carbonyl compounds using ferric chloride adsorbed on silica gel under microwave irradiation in excellent yields.
- Bose,Venkat Narsaiah,Ravinder Goud
-
p. 719 - 721
(2007/10/03)
-
- Quinolinium fluorochromate: An efficient reagent for the cleavage of C=N of oximes and hydrazones
-
Quinolinium Fluorochromate (QFC) was found to be an efficient oxidant for the conversion of C=N of oximes, tosylhydrazones and N,N- dimethylhydrazones to yield their corresponding carbonyl compounds in good to excellent yields.
- Bose, D. Subhas,Venkat Narasaiah
-
p. 1153 - 1158
(2007/10/03)
-
- Regeneration of carbonyl compounds from oximes and hydrazones using peroxymonosulfate on silica gel under solvent-free conditions
-
In an environmentally benign solvent-free system, oximes and hydrazones are rapidly transformed into parent carbonyl compounds using peroxymonosulfate on silica gel under microwave irradiation in good to excellent yields.
- Bose, D. Subhas,Venkat Narsaiah,Lakshminarayana
-
p. 3121 - 3125
(2007/10/03)
-
- A novel one-step conversion of α,β-epoxy ketones to o-dichlorobenzaldehydes by the Vilsmeier reaction
-
A novel, versatile one-step synthesis of o-dichlorobenzaldehydes has been developed. Acyclic α,β-epoxy ketones undergo the Vilsmeier reaction to afford o-dichlorobenzenemono- and dicarboxyaldehydes whereas cyclic α,β-epoxy ketones gave des and chlorobenzenedicarboxyaldehydes.
- Megati, Sreenivasulu,Rao, Krishna G. S.
-
p. 5819 - 5822
(2007/10/02)
-
- Novel synthesis of α-acetylstyrylphosphonates
-
α-Acetylstyrylphosphonates were conveniently synthesized from 2-oxopropylphosphonates and substituted (dimorpholinomethyl)-benzenes (animals). 4-Benzylidenemorpholinium carboxylates, generated from animals by the action of α-halo acids, reacted with the phosphonates to give the products by elimination of the amine. The yields were influenced by the nature of substituents and their position in the phenyl ring and could be improved by adjustment of the acidities of the reacted acids. α-Acetylstyrylphosphonates containing various substituents on every position (at the 2-, 3-, or 4-position) in the phenyl ring were obtained generally in excellent yields using monochloroacetic acid.
- Sakoda,Matsumoto,Seto
-
p. 705 - 713
(2007/10/02)
-
- Bis(methylenedioxyphenyl)imidazoles
-
A 2,4-5-triphenylimidazole compound having the formula: STR1 wherein each of R1 to R5 is a hydrogen atom, a C1 -C4 alkyl group, a C1 -C4 alkoxy group, a fluorine atom, a chlorine atom, a bromine atom, a trifluoromethyl group or a trichloromethyl group, and A is a group having the formula: STR2 wherein R1 and R5 are as defined above. These compounds are useful as chlorine sources for photographic image-forming compositions, and as intermediates for dimers of 2,4-5-triphenylimidazoles which are useful as photochromic agents in sunglasses.
- -
-
-
- Dihydropyridines
-
Dihydropyridine anti-ischaemic agents of the formula: STR1 and their salts where R is aryl or heteroaryl, R1 and R2 are each C1 -C4 alkyl or 2-methoxyethyl, Y is --(CH2)n -- where n is 2, 3, or 4 and is optionally substituted by 1 or 2 CH3 groups, and R3 is an optionally substituted 5- or 6-membered heterocyclic group attached to the adjacent N atom by a C atom, said group R3 being optionally fused to a further heterocyclic group or to a benzene ring.
- -
-
-
- 2-(SECONDARY AMINOALKOXYMETHYL) DIHYDROPYRIDINE DERIVATIVES AS ANTI-ISCHAEMIC AND ANTIHYPERTENSIVE AGENTS
-
A dihydropyridine compound of the formula or a pharmaceutically acceptable acid addition salt thereof, wherein Y is -(CH2)2-, -(CH2)3-, -CH2CH(CH3)-or -CH2C(CH3)2-; R is aryl or heteroaryl; R1 and R2 are each independently C1-C4 alkyl or 2-methoxyethyl; and R3 is hydrogen, C1-C4 alkyl, 2-(Ci-C4 alkoxy)ethyl, cyclopropylmethyl, benzyl, or -(CH2)mCOR4 where m is 1, 2 or 3 and R4 is hydroxy, C1-C4 alkoxy or -NR5R6 where R5 and R6 are each independently hydrogen or C1-C4 alkyl can be employed for treating or preventing a heart condition or hypertension.
- -
-
-
- Dihydropyridine derivatives of 1,4:3,6-dianhydrohexitols
-
The present invention relates to new acyl derivatives of 1,4:3,6-dianhydrohexitols, processes for their preparation and drugs containing the same. The new compounds have a cardiovascular effect and can be used as antihypertensive agents, as peripheral and central vasodilators and as coronary therapeutic agents.
- -
-
-
- 7-Substituted Benzothiophenes and 1,2-Benzisothiazoles. Part 2. Chloro and Nitro Derivatives
-
The 7-chloro and 7-nitro derivatives of benzothiophene and 1,2-benzisothiazole have been prepared from readily available precursors, which for each substituent are common to both ring systems. 7-Chlorobenzothiophene has been obtained from 3-chloro-2-mercaptobenzoic acid via 7-chlorobenzothiophen-3(2H)-one, or from 2,3-dichlorobenzaldehyde, either via β-(2,3-dichlorophenyl)-α-mercaptoacrylic acid (16) or, preferably, via 7-chlorobenzothiophene-2-carboxylic acid.Hexamethylphosphoric triamide is a particularly useful solvent in which to effect the selective nucleophilic replacement of the 2-chloro substituent in 2,3-dichlorobenzaldehyde. 7-Chloro-1,2-benzisothiazole is available by treatment of 3-chloro-2-mercaptobenzaldehyde with chloramine (57percent), or by heating 2,3-dichlorobenzaldehyde with sulphur and aqueous ammonia (46percent). 7-Nitrobenzothiophene has been obtained by treatment of 2-bromo-3-nitrobenzaldehyde with mercaptoacetic acid under alkaline conditions, followed by decarboxylation of the resulting 2-carboxylic acid.Cyclisation of 2-(n- or t-butylthio)-3-nitrobenzaldoxime with polyphosphoric acid gives 7-nitro-1,2-benzisothiazole in high yield. 3-Nitro-2-t-bytylthiobenzaldehyde behaves unexpectedly with chloramine, to give what is believed to be 7-nitro-2-t-butyl-1,2-benzothiazolium chloride (24) (73percent).
- Rahman, Loay K. A.,Scrowston, Richard M.
-
p. 385 - 390
(2007/10/02)
-
- Antihypertensive Activity of 6-Arylpyridopyrimidin-7-amine Derivatives
-
A series of 51 6-arylpyridopyrimidin-7-amine derivatives was prepared and evaluated for antihypertensive activity in the conscious spontaneously hypertensive rat.A number of these compounds, notably 6-(2,6-dichlorophenyl)-2-methylpyridopyrimidin-7-amine (36), lowered blood pressure in these rats in a gradual and sustained manner to normotensive levels at oral doses of 10-50 mg/kg.Normalized blood pressure levels could then be maintained by single daily oral doses.The effect of structural variation in the 6-aryl group and in the 2 and 4 positions of the pyridopyrimidine ring on activity is reported and discussed.
- Bennett, Lawrence R.,Blankley, C. John,Fleming, Robert W.,Smith, Ronald D.,Tessman, Deirdre K.
-
p. 382 - 389
(2007/10/02)
-
