Interfacial microstructure and mechanical properties of Cf/AZ91D composites with TiO2 and PyC fiber coatings

An alternative method for the preparation of vismodegib: A tool for an undergraduate laboratory course

“…3 2-(2-Chloro-5-nitrophenyl)pyridine is the key intermediate for the synthesis of vismodegib, which is converted into 4-chloro-3-(pyridin-2-yl)aniline via a reduction reaction, which is then reacted with commercially available 2-chloro-4-methylsulfonylbenzoic acid to afford vismodegib (Scheme 1). [4][5][6][7][8][9][10][11] Seven representative synthetic routes to 2-(2-chloro-5-nitrophenyl)pyridine have been reported in the literature. The main difference between these routes are the construction of the phenyl pyridine, for which there were two described methods: a coupling reaction catalyzed by a metal catalyst, such as in routes A-D, [5][6][7][8] and a cyclization reaction utilizing appropriate functional groups on the substituted benzene, such as in routes E-G. [9][10][11] Catalysts containing palladium are employed to synthesize the key intermediate in routes A-E, which increases the complexity of purification due to the low limits of palladium residue in drugs.…”

“…[4][5][6][7][8][9][10][11] Seven representative synthetic routes to 2-(2-chloro-5-nitrophenyl)pyridine have been reported in the literature. The main difference between these routes are the construction of the phenyl pyridine, for which there were two described methods: a coupling reaction catalyzed by a metal catalyst, such as in routes A-D, [5][6][7][8] and a cyclization reaction utilizing appropriate functional groups on the substituted benzene, such as in routes E-G. [9][10][11] Catalysts containing palladium are employed to synthesize the key intermediate in routes A-E, which increases the complexity of purification due to the low limits of palladium residue in drugs. In addition, the use of precious metals will increase the synthetic costs.…”

“…In terms of the reduction of 2-(2-chloro-5-nitrophenyl) pyridine, catalytic hydrogenation using molecular hydrogen and reduction using Fe under acidic conditions are the most commonly used methods reported in the literature (Scheme 1). [4][5][6][7][8][9][10][11] Catalytic hydrogenation is environmentally friendly and widely used in industry; however, as mentioned earlier, metal residues in drugs will be encountered due to the use of palladium or platinum, and the determination of their levels is necessary. Besides, the use of pressurized equipment is required, but some laboratories cannot use hydrogen gas cylinders due to safety reasons.…”

Mean-field model analysis of deformation and damage in friction stir processed Mg-C composites

“…squeeze casting or stir casting, are faced with important issues related to the matrix/reinforcement interface. On one hand, for C fibre MgMCs, the poor wettability between carbon and pure Mg [4][5][6] may result in inadequate distribution of the reinforcing phase in the metallic matrix [2,7]. On the other hand, excessive interfacial reactions between the reinforcement and the molten metal may prove detrimental to the integrity and mechanical behaviour of the composite.…”

“…These poor mechanical properties are due to a significant degradation of the reinforcement and/or to the formation of brittle intermetallic compounds. In particular, extensive undesirable reactions have been reported between carbon and Mg alloys with a high Al content (such as alloy AZ91D) in the liquid-state and for high processing temperature [4,6,8]. Poor interface bonding may lead to premature failure by matrix decohesion from the C fibre [9].…”