A new synthetic route to α—damascone (4) starting from citral is described-The synthesis features allylatioa of α—cyclocitral (1) with allylic bromide in the presence of tin powder to give the crucial intermediat...A new synthetic route to α—damascone (4) starting from citral is described-The synthesis features allylatioa of α—cyclocitral (1) with allylic bromide in the presence of tin powder to give the crucial intermediate 1—(2',6',6'—trimethylcyclo— hexen —2'—yl)—3—buten —1—ol(2a) and (2b) in a combined yield of 70%.展开更多
In recent years,the organometallic ehemistry of the lanthanide metals in low oxidation states has beenactively investigated.The synthesis of the low一valent lanthanide eomPlexes has the signifieant meanings ontheory a...In recent years,the organometallic ehemistry of the lanthanide metals in low oxidation states has beenactively investigated.The synthesis of the low一valent lanthanide eomPlexes has the signifieant meanings ontheory and praeti展开更多
In order to make the synthetic route of Thiamidol more efficient and easier to scale up,a new method was developed.The compound 2,4-dihydroxyacetophenone was dissolved in ethyl acetate and brominated with cupric bromi...In order to make the synthetic route of Thiamidol more efficient and easier to scale up,a new method was developed.The compound 2,4-dihydroxyacetophenone was dissolved in ethyl acetate and brominated with cupric bromide.After bromination,the mixture was filtered to remove cuprous bromide.The obtained ethyl acetate solution containing 2-bromo-1-(2,4-dihydroxyphenyl)ethanone was directly reacted with(2-methylpropanoyl)thiourea to obtain the precipitate of Thiamidol hydrobromide.The precipitate was neutralized by deacidification and recrystallized to afford Thiamidol with high purity.In addition,in the screening of fertility-promoting substances,Thiamidol was found to be effective in protecting human sperm from motility loss in vitro.This suggests that it may have potential application in fertility protection and promotion.展开更多
The progress made by the scientific community in emerging photovoltaic technologies over the past two decades has been outstanding. Numerous methods have been developed for the preparation of hybrid organic–inorganic...The progress made by the scientific community in emerging photovoltaic technologies over the past two decades has been outstanding. Numerous methods have been developed for the preparation of hybrid organic–inorganic perovskite solar cells. The power conversion efficiency has been up to 14% by a one-step vacuum deposition technique. A serious concern is the toxicity of the materials. In this review, several methods aimed at resolving these problems to some extent have been compiled, including eco-friendly synthesis. Further efficiency enhancements are expected following optimization, and a better fundamental understanding of the internal electron charge transfer, electron–hole diffusion to the corresponding layers, flexibility, and stability-dependent bandgaps is reported. This paper explores the green synthesis of organic–inorganic perovskites for industrialization. Concerning the above facts, a simple low-cost model called‘‘dispersed photovoltaic cells' ' is presented.展开更多
Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate)(PDEFMV),a novel bio-based elastomer with a saturated structure,was synthesized via redox emulsion polymerization.The glass-transition temperatures...Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate)(PDEFMV),a novel bio-based elastomer with a saturated structure,was synthesized via redox emulsion polymerization.The glass-transition temperatures of PDEFMV,adjusted through the variation of the diethyl fumarate-to-methoxyethyl acrylate feeding ratio,ranged from-36.1 to-14.8 ℃.The number-average molecular weights of PDEFMV ranged from 384,000 to 46,000 g/mol.In designing the molecular structure,vinyl chloroacetate was used to provide active sites for subsequent vulcanization and crosslinking.The active chlorine groups within the PDEFMV chain reacted with the crosslinking agent trithiocyanuric acid under high temperature and pressure to form a nonsulfur crosslinked three-dimensional network structure.To achieve the desired properties,carbon black(CB,N330) was incorporated to reinforce PDEFMV,leading to the formation of PDEFMV/CB composites.A comprehensive study was conducted on the high-temperature oil resistance of PDEFMV/CB composites.Following immersion in IRM903 oil at temperatures of 150 and 200 ℃ for 72 h,the mass and volume changes in PDEFMV/CB were lower than those observed in commercially available acrylate rubber(AR)/CB,indicating that PDEFMV exhibited superior oil resistance.Furthermore,the aging characteristics and mechanisms of oil resistance in the PDEFMV/CB and AR/CB composites were investigated at different temperatures(150,200,and 250 ℃).The results provide insights into the operational temperature ranges suitable for PDEFMV/CB and offer valuable guidance for potential industrial applications.展开更多
文摘A new synthetic route to α—damascone (4) starting from citral is described-The synthesis features allylatioa of α—cyclocitral (1) with allylic bromide in the presence of tin powder to give the crucial intermediate 1—(2',6',6'—trimethylcyclo— hexen —2'—yl)—3—buten —1—ol(2a) and (2b) in a combined yield of 70%.
文摘In recent years,the organometallic ehemistry of the lanthanide metals in low oxidation states has beenactively investigated.The synthesis of the low一valent lanthanide eomPlexes has the signifieant meanings ontheory and praeti
基金Development Fund for Shanghai Talents,China(No.15431903000)。
文摘In order to make the synthetic route of Thiamidol more efficient and easier to scale up,a new method was developed.The compound 2,4-dihydroxyacetophenone was dissolved in ethyl acetate and brominated with cupric bromide.After bromination,the mixture was filtered to remove cuprous bromide.The obtained ethyl acetate solution containing 2-bromo-1-(2,4-dihydroxyphenyl)ethanone was directly reacted with(2-methylpropanoyl)thiourea to obtain the precipitate of Thiamidol hydrobromide.The precipitate was neutralized by deacidification and recrystallized to afford Thiamidol with high purity.In addition,in the screening of fertility-promoting substances,Thiamidol was found to be effective in protecting human sperm from motility loss in vitro.This suggests that it may have potential application in fertility protection and promotion.
基金CONACYT for a postdoctoral research fellowship (Fellowship:24641)support by CONACYT (Grant: 240011)UANL-FCQ
文摘The progress made by the scientific community in emerging photovoltaic technologies over the past two decades has been outstanding. Numerous methods have been developed for the preparation of hybrid organic–inorganic perovskite solar cells. The power conversion efficiency has been up to 14% by a one-step vacuum deposition technique. A serious concern is the toxicity of the materials. In this review, several methods aimed at resolving these problems to some extent have been compiled, including eco-friendly synthesis. Further efficiency enhancements are expected following optimization, and a better fundamental understanding of the internal electron charge transfer, electron–hole diffusion to the corresponding layers, flexibility, and stability-dependent bandgaps is reported. This paper explores the green synthesis of organic–inorganic perovskites for industrialization. Concerning the above facts, a simple low-cost model called‘‘dispersed photovoltaic cells' ' is presented.
基金supported by the National Key Research and Development Program of China (2022YFC2104700)the National Natural Science Foundation of China (52273003,51988102)。
文摘Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate)(PDEFMV),a novel bio-based elastomer with a saturated structure,was synthesized via redox emulsion polymerization.The glass-transition temperatures of PDEFMV,adjusted through the variation of the diethyl fumarate-to-methoxyethyl acrylate feeding ratio,ranged from-36.1 to-14.8 ℃.The number-average molecular weights of PDEFMV ranged from 384,000 to 46,000 g/mol.In designing the molecular structure,vinyl chloroacetate was used to provide active sites for subsequent vulcanization and crosslinking.The active chlorine groups within the PDEFMV chain reacted with the crosslinking agent trithiocyanuric acid under high temperature and pressure to form a nonsulfur crosslinked three-dimensional network structure.To achieve the desired properties,carbon black(CB,N330) was incorporated to reinforce PDEFMV,leading to the formation of PDEFMV/CB composites.A comprehensive study was conducted on the high-temperature oil resistance of PDEFMV/CB composites.Following immersion in IRM903 oil at temperatures of 150 and 200 ℃ for 72 h,the mass and volume changes in PDEFMV/CB were lower than those observed in commercially available acrylate rubber(AR)/CB,indicating that PDEFMV exhibited superior oil resistance.Furthermore,the aging characteristics and mechanisms of oil resistance in the PDEFMV/CB and AR/CB composites were investigated at different temperatures(150,200,and 250 ℃).The results provide insights into the operational temperature ranges suitable for PDEFMV/CB and offer valuable guidance for potential industrial applications.