氟班色林的合成新方法

本文通过醋酸碘苯促进的苯甲醛、N-苯基羟胺和三甲基氰硅烷的一锅法反应首先构建氟班色林的重要骨架苯并咪唑酮结构,随后,与1,2-二溴乙烷反应得到中间体8,接着在浓盐酸中水解,得到中间体9,最后与哌嗪盐酸盐10反应,以29%的总收率得到氟班色林11。所有化合物的结构经过1H NMR、13C NMR、HRMS表征。该方法具有原料价廉易得、副产物少、收率较高等特点。     

A novel synthesis route to furo[3,2-a]carbazole

In this paper,we report a novel approach to the heteroaryl-condensed nuclei of natural furo[3,2-a]carbazole alkaloids.Our synthetic studies use N-phthaloyl tryptophan methyl ester as starting material and zinc ion mediated transamination reaction as the key step.This work also implicated a novel strategy to assemble other [a]-fused carbazoles.     

A novel synthesis route for ethylenediamine-protected ruthenium nanoparticles

A novel method has been developed to prepare water-dispersible ethylenediamine (en)-stabilized ruthenium nanoparticles. The procedure involves the reduction of an en-RuCl(3) complex by sodium borohydride. The Ru nanoparticles so prepared are fairly stable in water. TEM imaging shows a mean diameter of about 2.1 nm for the particles and a narrow particle size distribution.     

A novel route to meta-aminobenzotrifluoride

Product patterns can be altered in reactions of $\text{m}$-nitrobenzotrichloride [VI] with [AHF]_x·NH₄F complex. Side-chain fluorination predominates under ‘mild’ conditions. In contrast. ‘forcing’ conditions affected unexpected $\text{in}$-$\text{situ}$ fluorination-reduction to give $\text{m}$-aminobenzotrifluoride [V] in high yield [75%] and purity [99.6%]. $\text{in}$-$\text{situ}$ reduction is probably initiated by a combination of iron from the stainless steel autoclave and trace amounts of moisture. The transformation of [VI] to [V] represents another type of $\text{in}$-$\text{situ}$ fluorination-reduction nitroaromatics, e.g. nitrobenzene [VII] to $\text{p}$-fluoroaniline [VIII]. $\text{o}$-Nitrobenzotrichloride [XI] degraded under ‘forcing’ conditions with [AHF]_x·NH₄F.     

A novel route to synthesis of flavones from salicylaldehyde and acetophenone derivatives

Convenient, facile, and alternate synthesis of medicinally important flavones is reported. The 2-hydroxychalcones derived from condensation between acetophenones and salicylaldehyde, underwent oxidative cyclization on heating in the presence of catalytic iodine, generating diversified flavones under solvent-free conditions. Eleven compounds have been synthesized in good to excellent yields and their mechanism of formation is described.     

Stereoselective synthesis of novel five-membered homoazasugars. A convenient route to all-cis tetrasubstituted pyrrolidines

We present a highly stereoselective procedure for the preparation of (2S and 2R,3S,4R,5S)-5-methyl-3,4-dihydroxy-2- ethoxycarbonylmethylpyrrolidines based on conjugate addition of ammonia to unsaturated aldonic esters derived from d-ribose followed by tandem cyclization. Derivatisation of these compounds to 2-hydroxyethyl-, benzymidazolylmethyl-, biphenyl-1-aminoethyl and naphthalene-l-aminoethyl-pyrrolidines is also presented.     

A novel efficient and versatile route to the synthesis of 5-O-feruloylquinic acids

A novel synthesis of 5-O-feruloylquinic acid, a polyphenolic compound found in coffee beans, and its methyl ester derivative has been optimized. The sequence involves 6 steps and is compatible with the preparation of potential human metabolites of these compounds. The key reaction is a Knoevenagel condensation of 4-hydroxy-3-methoxy-benzaldehyde and a malonate ester of quinic acid.     

A novel route to imidoylbenzotriazoles and their application for the synthesis of enaminones

Reactions of secondary amides 2a-i with 1-chloro-1H-benzotriazole and triphenylphosphine give imidoylbenzotriazoles 3a-i. The treatment of 3a,b,e,g with silyl enol ethers 5a,b in the presence of potassium tert-butoxide provides a new general approach to enaminoketones 6a-h.     

A novel route to pH oscillators

The formaldehyde–sulfite reaction is an acid to alkali clock reaction in batch, which displays complex behaviour in a flow reactor. Current published mechanisms do not account for the behaviour in an open system. In this Letter, we construct a minimal model based on this system and demonstrate that a base-catalysed rate-determining step coupled with an appropriate OH⁻ consuming reaction can result in bistability and oscillations. The model may provide a method for the design of organic-based pH oscillators.     

Fluoride-free and seed-free microwave-assisted hydrothermal synthesis of nanosized high-silica Beta zeolites for effective VOCs adsorption

High-silica Beta zeolites, typically synthesized by hydrothermal synthesis with the assistance of F⁻ or seeds, are highly important in volatile organic compounds (VOCs) adsorption. Fluoride-free or seed-free synthesis of high-silica Beta zeolites attracts great attention. Herein, highly dispersed Beta zeolites with a size of 25–180 nm and Si/Al ratios of 9–∞ were successfully synthesized by a microwave-assisted hydrothermal strategy. We have for the first time revealed that microwave irradiation can induce the formation of hydroxyl free radicals (˙OH), promoting the formation of the Si–O–Si bond. Thanks to the high total surface area, pore volume, and excellent hydrophobicity, the as-prepared pure-silica Beta zeolite presents a higher toluene adsorption capacity in VOCs adsorption compared to other pure-silica Beta zeolites prepared by traditional methods. This work provides a facile avenue for fluoride-free and seed-free synthesis of nanosized high-silica zeolites, promising their important applications in VOCs adsorption.

A facile fluoride-free and seed-free microwave-assisted hydrothermal strategy is developed to prepare nanosized pure-silica Beta zeolites for VOCs adsorption.     

A novel route to thioketenes by flash vacuum thermolysis of silylatedketene dithioacetals,synthesis of propadienethione.

Flash vacuum thermolysis (fvt) of silylated ketene dithioacetals 2 leads to reactive thioketenes 1. This method, added to a retrodienic reaction, allowedaccess to propadienethione 3.     

A new synthetic route to produce metal zeolites with subnanometric magnetic clusters

By using a Co layered silicate as a source of Co and SiO(2), Co-Beta and Co-ZSM-5 zeolites with tetrahedrically coordinated cobalt were synthesized. Subnanometric clusters of Co can be produced and a magnetic material with superparamagnetic-paramagnetic phase transition is obtained.     

Application of nanosized zeolites in methanol conversion processes: A short review

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A novel route to 2,4-dianilino-substituted pyrimidines

A method is described to couple sterically-hindered electron-poor anilines to the 4-position of the pyrimidine core using a pyrimidine-2,4-bis(trifluoromethanesulfonate).     

A novel route for FePO4 olivine synthesis from sarcopside oxidation

Heterosite FePO₄ is synthesized for the first time by direct thermal oxidation of sarcopside Fe₃(PO₄)₂. Both FePO₄ and Fe₃(PO₄)₂ have a pseudo olivine structure. Complete isostructural conversion of sarcopside into FePO₄ is achieved at a temperature of 450 °C within 3 days according to the reaction Fe₃(PO₄)₂ + ¾ O₂ → 2 FePO₄ + ½ Fe₂O₃ which leads to the extraction of iron from the sarcopside structure. Appropriate heating ramp must be applied in order to avoid the crystallization of Fe₇(PO₄)₆. Electrochemical performances of the oxidation product are consistent with those of olivine FePO₄.