50-30-6Relevant articles and documents
A tunable synthesis of either benzaldehyde or benzoic acid through blue-violet LED irradiation using TBATB
Mardani, Atefeh,Heshami, Marouf,Shariati, Yadollah,Kazemi, Foad,Abdollahi Kakroudi, Mazaher,Kaboudin, Babak
, (2019/11/29)
In this paper, a highly efficient, metal-free, and homogeneous method for the selective aerobic photooxidation of alcohols and photooxidative-desilylation of tert-butyldimethylsilyl ethers (TBDMS) in the presence of tetrabutylammonium tribromide (TBATB) under irradiation of visible light was reported. The light source: blue (460 nm) and violet (400 nm) LED, can control selective oxidation to aldehyde or carboxylic acid.
Synthesis and Characterization of Acridinium Dyes for Photoredox Catalysis
White, Alexander R.,Wang, Leifeng,Nicewicz, David A.
supporting information, p. 827 - 832 (2019/04/25)
Photoredox catalysis is a rapidly evolving platform for synthetic methods development. The prominent use of acridinium salts as a sustainable option for photoredox catalysts has driven the development of more robust and synthetically useful versions based on this scaffold. However, more complicated syntheses, increased cost, and limited commercial availability have hindered the adoption of these catalysts by the greater synthetic community. By utilizing the direct conversion of a xanthylium salt into the corresponding acridinium as the key transformation, we present an efficient and scalable preparation of the most synthetically useful acridinium reported to date. This divergent strategy also enabled the preparation of a suite of novel acridinium dyes, allowing for a systematic investigation of substitution effects on their photophysical properties.
Table salt as a catalyst for the oxidation of aromatic alcohols and amines to acids and imines in aqueous medium: Effectively carrying out oxidation reactions in sea water
Hazra, Susanta,Kushawaha, Ajay Kishor,Yadav, Deepak,Dolui, Pritam,Deb, Mayukh,Elias, Anil J.
supporting information, p. 1929 - 1934 (2019/04/29)
A simple, efficient, sustainable and economical method for the oxidation of alcohols and amines has been developed based on chloride, a sea abundant anionic catalyst for the practical synthesis of a wide range of carboxylic acids, ketones and imines. Oxidation of aromatic alcohols was carried out using NaCl (20 mol%) as the catalyst, NaOH (50 mol%) and aq. TBHP (4 equiv.) as the oxidant in 55-92% isolated yields. Oxidation of aromatic amines to imines was achieved by using only 20 mol% of NaCl and aq. TBHP (4 equiv.) in 32-93% isolated yields. The chlorine species formed during the reaction as the active oxidation catalyst has been identified as ClO2- for alcohols and ClO-/ClO2- for amines by control experiments. This method is mostly free from chromatographic purification, which makes it suitable for large-scale synthesis. We have scaled up to 30 gram scale the synthesis of carboxylic acids and imines in good yields and have also carried out efficiently this new method using filtered sea water as the solvent and catalyst.
Iodine catalyzed oxidation of alcohols and aldehydes to carboxylic acids in water: A metal-free route to the synthesis of furandicarboxylic acid and terephthalic acid
Hazra, Susanta,Deb, Mayukh,Elias, Anil J.
supporting information, p. 5548 - 5552 (2017/12/06)
A metal-free iodine/NaOH-catalyzed oxidation of alcohols and aldehydes has been developed for the practical synthesis of a wide range of carboxylic acids using water as the solvent. This transformation involves dehydrogenation of an alcohol, followed by a fast attack of water on an aldehyde. This method is mostly free from chromatographic purification, which makes it suitable for large-scale synthesis. The iodine species formed during the reaction as the active oxidation catalyst has been deduced as IO2- by control experiments. We also demonstrate a 10 gram scale synthesis of furandicarboxylic acid (FDCA) from HMF in good yield using our method.
Ultrasmall Platinum Nanoparticles Supported Inside the Nanospaces of Periodic Mesoporous Organosilica with an Imidazolium Network: An Efficient Catalyst for the Aerobic Oxidation of Unactivated Alcohols in Water
Karimi, Babak,Naderi, Zahra,Khorasani, Mojtaba,Mirzaei, Hamid M.,Vali, Hojatollah
, p. 906 - 910 (2016/03/15)
The imidazolium group inside the wall of a periodic mesoporous organosilica provides an excellent environment for the stabilization of ultrasmall Pt nanoparticles ((NP)@PMO-IL) with significant activity and recyclability in the selective aerobic oxidation of various alcohols in water at ambient pressure of oxygen. In particular, the catalyst exhibited high activity in the oxidation of unactivated primary alcohols and sterically encumbered secondary aliphatic alcohols, which remain challenging substrates for many catalytic aerobic protocols.
A high-throughput screening method for determining the substrate scope of nitrilases
Black, Gary W.,Brown, Nicola L.,Perry, Justin J. B.,Randall, P. David,Turnbull, Graeme,Zhang, Meng
supporting information, p. 2660 - 2662 (2015/03/05)
Nitrile compounds are intermediates in the synthesis of pharmaceuticals such as atorvastatin. We have developed a chromogenic reagent to screen for nitrilase activity as an alternative to Nessler's reagent. It produces a semi-quantifiable blue colour and hydrolysis of 38 nitrile substrates by 23 nitrilases as cell-free extracts has been shown. This journal is
An insight into the mechanism of the aerobic oxidation of aldehydes catalyzed by N-heterocyclic carbenes
Bortolini,Chiappe,Fogagnolo,Giovannini,Massi,Pomelli,Ragno
supporting information, p. 2008 - 2011 (2014/03/21)
N-Heterocyclic carbene catalysis for the aerobic oxidation and esterification of aromatic aldehydes was monitored by ESI-MS (MS/MS) and the key intermediates were intercepted and characterized using the charge-tag strategy.
Electrophilicity and nucleophilicity of commonly used aldehydes
Pratihar, Sanjay
, p. 5781 - 5788 (2014/07/22)
The present approach for determining the electrophilicity (E) and nucleophilicity (N) of aldehydes includes a kinetic study of KMNO4 oxidation and NaBH4 reduction of aldehydes. A transition state analysis of the KMNO4 promoted aldehyde oxidation reaction has been performed, which shows a very good correlation with experimental results. The validity of the experimental method has been tested using the experimental activation parameters of the two reactions. The utility of the present approach is further demonstrated by the theoretical versus experimental relationship, which provides easy access to E and N values for various aldehydes and offers an at-a-glance assessment of the chemical reactivity of aldehydes in various reactions. the Partner Organisations 2014.
Nanoparticle-supported and magnetically recoverable organic-inorganic hybrid copper(ii) nanocatalyst: A selective and sustainable oxidation protocol with a high turnover number
Rathore, Puran Singh,Patidar, Rajesh,Thakore, Sonal
, p. 41111 - 41121 (2014/12/10)
A magnetically recoverable copper-based nanocatalyst was prepared from inexpensive starting materials. With a particle size between 20 to 30 nm, it was shown to catalyze the oxidation of benzylic alcohols. The catalyst exhibited a high turnover number (TON) and excellent selectivity. The catalyst was characterized by several techniques, such as XRD, HR-TEM, SAED, EDS, FT-IR, VSM, and BET surface area. Factors affecting the reaction parameters, such as the substrate to oxidant molar ratio, weight of the catalyst, reaction time, etc., were investigated in detail. The reusability of the catalyst was examined by conducting repeat experiments with the same catalyst; it was observed that the catalyst displayed no significant changes in its activity even after seven cycles for the aerobic, as well as for the peroxide, oxidation of benzyl alcohol. Furthermore, the heterogeneous nature, easy recovery, and reusability, makes the present protocol highly beneficial for addressing environmental concerns and industrial requirements. This journal is
An efficient one pot method for synthesis of carboxylic acids from nitriles using recyclable ionic liquid [bmim]HSO4 Dedicated to my mentor Professor (Mrs.) Krishna Misra on her 76th birthday
Kumar, Satyanand,Dixit, Sandeep Kumar,Awasthi, Satish Kumar
supporting information, p. 3802 - 3804 (2014/07/07)
Environmentally benign ionic liquid [bmim]HSO4 was found suitable for conversion of nitriles into carboxylic acids under mild conditions with excellent purity.
