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Synthesis of Low Nitrogen Cetane Improvers from the Nitration of Renewable Feedstocks
Published in Chunshan Song, Chang S. Hsu, Isao Mochida, Chemistry of Diesel Fuels, 2020
Mark H. Mason, Christopher Yan, Zhi Chen, Rajan Aggarwal, Joseph A. Heppert, Galen J. Suppes
Synthesis and testing of internal dinitrates of fatty esters as cetane improvers. As Figure 10−2 demonstrates, the internal double bonds in these oils offer convenient routes to energetic materials. These alkenes are readily epoxidized by performic acid. The resultant epoxides are hydrolyzed with dilute HC1 to yield diols, which are readily nitrated with acetyl nitrate to give vicinal dinitrates. In a more efficient route, the epoxide can be ring opened by N2O5 in a single step to yield the dinitrate.
Alkenes and Alkynes: Structure, Nomenclature, and Reactions
Published in Michael B. Smith, A Q&A Approach to Organic Chemistry, 2020
A diol is a molecule with two hydroxyl units (OH), such as ethanediol (ethylene glycol): HOCH2CH2OH. What is the structure of pentane-1,2-diol? Of cyclopentane-1,2-diol?
Metabolic Engineering for the Production of a Variety of Biofuels and Biochemicals
Published in Kazuyuki Shimizu, Metabolic Regulation and Metabolic Engineering for Biofuel and Biochemical Production, 2017
Diols have two hydroxyl groups, and give a wide range of industrial applications for chemicals and fuels. In particular, the microbial production of 1,3-propandiol (1,3-PDO), 1,2-propandiol (1,2-PDO), 2,3-butanediol (2,3- BDO), 1,4-butanediol (1,4-BDO), and 1,3-butanediol (1,3-BDO) has been paid recent attention (Zheng et al. 2011).
Optimisation of a Ce–Mn co-doped SnO2–Sb anode based on a nanotubular TiO2 array for electrochemical decolourisation of wastewater
Published in Transactions of the IMF, 2023
Shengyan Ge, Mengyao Shao, Xingfu Zhou
Studies have shown that the precursor solvent for preparing the electrode has an important influence on the morphology and electrochemical performance of the electrode33. The use of polymeric precursors can generate a network-like polymer metal ion complex, this structure is conducive to the adhesion of the electrocatalytically active metal oxide onto the electrode surface, and increases the surface area of the electrode after the calcination. Therefore, the cerium-manganese co-doped Ti/TiO2–NTs/TiO2–SnO2–Sb prepared by using ethylene glycol (ethane diol) as the solvent were investigated. From Figure 9(a), it can be seen that the electrode prepared with ethylene glycol as the solvent has the best decolourisation extent of the simulated dye wastewater, and the decolourisation extent of methylene blue reaches 98.5% in 30 min, while the decolourisation extent of the electrode using normal butanol and ethanol as solvents is 89% and 81%, respectively. Ethylene glycol was used as the optimal solvent in fabrication of cerium-manganese co-doped Ti/TiO2–NTs/TiO2–SnO2–Sb electrode. It can be seen from Figure 9(b) that dye concentration decays exponentially with time, in accordance with the decay law in the process of intermittent electrolysis.
A convenient four-component reaction for the synthesis of dithiocarbamates starting from naphthols in water
Published in Journal of Sulfur Chemistry, 2020
Maryam Khalili Foumeshi, Rohollah Haghi, Petr Beier, Azim Ziyaei Halimehjani
To a solution of 1 (5 mmol, 1 equiv) in H2O (5 mL) was added CS2 (10 mmol, 2 equiv). The reaction mixture was stirred at room temperature for 30 min. Then the naphthol derivative (5 mmol, 1 equiv) was added followed by the addition of formaldehyde (5 mmol, 1 equiv). Stirring was continued at room temperature for overnight (14–16 h). In most of the cases, the product was obtained by filtration. In the case of oily products, the reaction mixture was extracted with EtOAc, the organic phase dried over Na2SO4 and evaporated in a rotary evaporator to afford the product. If needed, further purification was carried out by recrystallization in a minimum amount of EtOAc or by column chromatography. In the case of naphthalene-2,3-diol, two equivalents of amine and formaldehyde and four equivalents of CS2 were used.
New latent metathesis catalysts equipped with exchangeable boronic ester groups on the NHC
Published in Journal of Coordination Chemistry, 2018
Revannath Sutar, Danielle Butilkov, N. Gabriel Lemcoff, Ofer Reany
Our initial attempts were based on a very general synthetic strategy through Williamson’s etherification of a phenolic NHC salt (2) with different generations of the dendryl bromides (GnBr) [29]. Thus, diamine 1 [30] was converted to the NHC salt 2 and was introduced to G0Br under several conditions of etherification (Scheme 1). However, due to the low solubility of the phenolate salts accompanied with the vulnerability of imidazolidinium salt toward basic reaction conditions, sluggish reactions and poor reproducibility were obtained. Therefore, an alternative multistep synthetic sequence was followed (Scheme 2). Thus, Williamson’s etherification of N-Boc protected 3,5-dimethyl-4-aminophenol (4) [31] with G0Br, followed by N-Boc deprotection with HFIP under microwave irradiation [32] afforded the alkylated aniline derivative 6a (Scheme 2). The latter was reacted with glyoxal in a toluene/ethanol mixture to afford diimine 7a; however, the reaction proceeded in low yields [33]. Fortunately, using trans-1,4-dioxane-2,3-diol as the glyoxal source significantly improved the yields of the condensation reaction [34]. After screening several solvent combinations, a mixture of THF and HFIP as a solvent system was found to be optimal for reduction of 7a to diamine 8a.