MOLECULES
·
2020
·Vol. 25
·期 4
·914
·
IF 3.267
Ligeng Wang,Chun Feng,Yan Zhang,Jun Hu
The regioselective mono-bromination of phenols has been successfully developed with KBr and ZnAl–BrO3−–layered double hydroxides (abbreviated as ZnAl–BrO3−–LDHs) as brominating reagents. The para site is much favorable and the ortho site takes the priority if para site is occupied. This reaction featured with excellent regioselectivity, cheap brominating reagents, mild reaction condition, high atom economy, broad substrate scope, and provided an efficient method to synthesize bromophenols.Keywords:phenol;bromination;regioselecitvity
研究领域:
有机化学
·
材料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2021
·
IF 4.354
Haopeng Wu,Chukai Shao,Di Wu,Liang Jiang,Hongquan Yin,Fu-Xue Chen
A highly regioselective protocol for intermolecular thiocyanation-amination of alkynes by N-thiocyano-dibenzenesulfonimide (NTSI) as the SCN and nitrogen sources has been developed. A C–S bond and C–N bond are simultaneously constructed in only one step. The reaction under simple mild conditions features a broad substrate scope, atom economy, high yields (up to 94%), and excellent functional group tolerance.
研究领域:
有机化学
·
合成化学
✓ 已验证
DOI
PubMed
高影响因子
Materials Research Express
·
2022
·Vol. 9
·期 3
·035101
·
IF 2.025
Yue Jiang,Yichen Cai,Jianping Li,Naibo Chen,Laigui Hu,Wenchong Wang,Qing-Miao Nie,Bo Yan
Oganic devices have gained much progress in the past decades, as a promising candidate for flexible/wearable electronics. However, the realization of organic microelectronic systems for wide applications is still difficult, due to the incompatibility of organic semiconductors (OSCs) with the conventional top-down lithography techniques for inorganics. To solve this challenge, bottom-up lithography-compatible methods have been developed for organic device arrays, i.e., template-directed growth or area-selective growth (ASG). Unfortunately, the physics on the dynamic process of the ASG method for molecular semiconductors is still not well understood. In order to explore this issue, the growth of particles on prepatterned surfaces under different diffusion lengths (Ld) was simulated in a microscopic point of view by using kinetic Monte Carlo method. Simulation results show that ASG of the particles is strongly related to the Ld of the particles, periodicity and size of prepatterned surfaces. It is notable that such simulated results were found to fit well with those of our experiments, which can be favorable for improving the ASG method for patterning functional molecules.
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2018
·Vol. 10
·期 5
·619-626
·
IF 4.927
Houbo Zhou,Christopher M. Plummer,Huaan Li,Huahua Huang,Pengfei Ma,Le Li,Lixin Liu,Yongming Chen
Previously, we developed amination modification of polyethylene by metal-free organocatalytic reaction. Here, we applied this chemistry to modify isotactic polypropylene (PP) to investigate the regioselectivity to different carbons. Specifically, this reaction was conducted in tetrachloroethane at 100 °C under a nitrogen protection where C–N bonds were selectively generated from the tertiary C–H bonds of the PP backbone in the presence of N-hydroxyphthalimide (NHPI) and bis(2,2,2-trichloroethyl) azodicarboxylate (BTCEAD). The grafting content of BTCEAD was as high as 4.7 units per 100 propylene units. Thus, a methodology for the regioselective post-functionalization of PP without metal catalysts has been developed. The obtained PP-g-BTCEAD was sequentially used as an atom transfer radical polymerization (ATRP) macro-initiator to graft polymers, such as polystyrene (PS) and poly(methyl) methacrylate (PMMA). The grafting polymerization was unequivocally proved by multiple characterization methods. The graft copolymers were applied as phase compatibilizers to improve blending of PP with PS and PMMA.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2015
·Vol. 33
·期 5
·792-796
·
IF 1.835
Liu Bo,Han Bao-yu,Zhang Chun-ling,Li Shi-hui,Sun Guang-ping,Cui Dong-mei
β -imidophosphonamido ligated lutetium alkyl complex (NPN Dipp )Lu(CH 2 SiMe 3 ) 2 (THF) (NPN Dipp = Ph 2 P(NC 6 H 3
i Pr 2 -2,6) 2 ) with the activation of Al i Bu 3 and [Ph 3 C][B(C 6 F 5 ) 4 ] exhibited high catalytic activity, medium syndio-(rr = 66%) but remarkably high 3,4-regioselectivity for the polymerization of β -myrcene (MY). In sharp contrast, high isotactic 3,4-polymyrcene (PMY) (mm = 95%) was obtained by the precursor (NPN Et )Lu(CH 2 SiMe 3 ) 2 (THF) (NPN Et = PPh 2 (NC 6 H 3
i Pr 2 -2,6)(NC 6 H 4 -Et-2)) with less bulky substituents on the N -aryl ring.
研究领域:
有机化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL COMMUNICATIONS
·
2017
·Vol. 53
·期 74
·10295-10298
·
IF 6.319
Huihuang Fang,Junmou Du,Chenchen Tian,Jianwei Zheng,Xinping Duan,Linmin Ye,Youzhu Yuan
Evenly dispersed tungsten carbides with controlled phase compositions that exhibit an impressive capacity to carry out the regioselective hydrogenolysis of inert aryl ether C–O bonds instead of aliphatic C–O bonds to produce aromatic compounds are reported.
研究领域:
催化
·
有机化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2020
·
IF 3.644
Bi Yanhong,Wang Zhaoyu,Tian Yaoqi,Fan Haoran,Huang Shuo,Lu Yihui,Jin Zhengyu
The immobilization of Thermomyces lanuginosus lipase on polydopamine-functionalized Fe3O4 magnetic nanoparticles (Fe3O4@PDA-TLL) as a nanobiocatalyst was successfully performed for the first time, and the Fe3O4@PDA-TLL was used for regioselective acylation of natural hyperoside with vinyl decanoate. The effects of several crucial factors, such as the reaction solvent, substrate molar ratio, temperature, and immobilized enzyme dosage, were investigated. Under optimum conditions, the reaction rate, 6″-regioselectivity, and maximum substrate conversion were as high as 12.6 mM/h, 100%, and 100%, respectively. An operational stability study demonstrated that the immobilized enzyme could maintain 90.1% of its initial maximum conversion even after reusing it five times. In addition, further investigations on the kinetic parameters, like Vmax, Km, Vmax/Km, and Ea, also revealed that the biocompatible Fe3O4@PDA could act as an alternative carrier for the immobilization of different enzymes.
研究领域:
生物化学
·
纳米生物学
·
酶工程
✓ 已验证
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 3.475
Rongling Yang,Tingting Wu,Ningning Xu,Xiangjie Zhao,Zhaoyu Wang,Hongzhen Luo,Muhammad Bilal,Zekun Nie,Yuye Song
Highly efficient and regioselective synthesis of pharmacologically useful 6′-O-benzoyl-helicid catalyzed by the whole-cell catalysts was successfully performed for the first time. The catalytic performance of Aspergillus oryzae whole cells for helicid benzoylation was significantly enhanced in acetone-ionic liquids (ILs) systems containing anions PF 6 , BF 4, and TF 2 N as compared to pure acetone. The catalytic performances of A. oryzae whole cells not only depend on the anion of ILs, but the cation. In acetone-[BMIM][PF 6 ] (5%, v/v) system, the substrate conversion efficiency reached 99 % at 24 h and initial reaction rate was achieved to be 7.42 mM/h, while 99 % substrate conversion was acquired at 72 h in acetone. Moreover, the A. oryzae whole cells showed excellent 6′-regioselectivity (99 %) and high operational stability in helicid benzoylation maintaining 75.5 % of its original activity after seven repeated reaction cycles in acetone-[BMIM][PF 6 ] (5%, v/v) system. In conclusion, the inclusion of a suitable level of ionic liquids might exhibit a high potential for improving whole-cell biocatalysis for helicid benzoylation in a regioselective and cost-effective manner.
研究领域:
生物化学
·
制药工程
✓ 已验证
DOI
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
·
2022
·Vol. 20
·期 7
·1510-1517
·
IF 3.89
Yang Liu,Meng Cao,Shangxi Zhang,Zhenxi Wang,Xin Dai,Xinde Jiang,Yucheng Dong,Jie Fu
A Brønsted acid catalyzed method for the construction of guaiazulenyl C3-functionalized indole derivatives is reported for the first time. The reactions proceeded smoothly at ambient temperature by using (±)-10-camphorsulfonic acid (CSA) as a catalyst, 2-indolylmethanols and guaiazulene as substrates, and the desired products were obtained in high yields with excellent regioselectivities.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
·
2015
·Vol. 117
·期 10
·1636-1646
·
IF 1.812
Lingyi Liu,Meirong Pang,Ying Zhang
AOB-w is a water-soluble antioxidant extracted from bamboo leaves, containing four flavone C-glucosides (orientin, isoorientin, vitexin, and isovitexin) as functional components. Flavone C-glucoside esters were firstly synthesized by three lipases (CALB, RM IM, and TL IM) in organic solvent system or solvent-free system. Results indicated that C12 fatty acid ester exhibited the optimal antioxidant capacity, CALB was the most efficient lipase in both systems, and higher conversion yields were achieved in solvent-free system. Highest conversion was obtained with 1% water content for CALB and 2% water content for RM IM and TL IM. All lipases displayed absolute 6″-regioselectivities with monoester. It is required to consider both of hydrophobicity and antioxidant capacity to prepare high-efficiency oil-soluble antioxidant. Regression equations were built up to illuminate the relationship between conversion yield of flavone C-glucoside and antioxidant capacity of its corresponding ester. Highest antioxidant capacity could be achieved when conversion yield was nearly 60% for flavone C-glucosides. Based on reaction parameters of flavone C-glucosides, high-efficiency eAOB-o was prepared, which could be expected as an excellent oil-soluble antioxidant in lipids. Practical applications: Water-soluble antioxidant of bamboo leaves (AOB-w) is a natural food antioxidant extracted from bamboo leaves, with four flavone C-glucosides (orientin, isoorientin, vitexin, and isovitexin) as functional components. This study aimed to provide a practical procedure to prepare high-efficiency lipid antioxidant by enzymatic acylation. Based on the optimal parameters from the synthesis of flavone C-glucoside esters, high-efficiency oil-soluble antioxidant of bamboo leaves (eAOB-o) was prepared. eAOB-o exhibited higher antioxidant capacity than cAOB-o, which has been approved as food antioxidants in China. High-efficiency acylation products were obtained by consideration both of lipid solubility and antioxidant capacity. Based on the rule, flavone C-glucoside ester and eAOB-o were prepared.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULAR DIVERSITY
·
2019
·Vol. 24
·期 2
·423-435
·
IF 2.032
Zheng Ran,Feng Fan,Zhang Zhihui,Fu Jiaxu,Su Qing,Zhang Yumin,Gu Qiang
Abstract An efficient strategy for synthesizing of 3-substituted bis-isoxazole ether bearing 2-chloro-3-pyridyl under microwave radiation was reported. The reactive regioselectivity was improved by changing mainly the solvent and acid-binding agent. 3-(2-Chloropyridin-3-yl)-5-(((3-substituted phenyl isoxazol-5-yl)methoxy)methyl)isoxazoles were synthesized in 31–92% yields and were characterized by FT-IR, HRMS, 1 H and 13 C NMR spectroscopy. The single crystal of 3-(2-chloropyridin-3-yl)-5-(((3-(p-tolyl)isoxazol-5-yl)methoxy)methyl)isoxazole was obtained, and the structure of compound has also been determined by X-ray diffraction technique. Weak intra- and intermolecular C–H∙∙∙O interactions and a C–H∙∙∙π interaction link molecules into a three-dimensional network. The results showed that the synthesized compounds belonged to triclinic system, and their regioselectivity depended on the solvent and acid-binding agent. The merits of this method include the environmentally friendly, efficient, simple operation, and higher regional selectivity. Graphic abstract An efficient synthesis of 3-substituted bis-isoxazole ethers was developed via 1,3-dipolar cycloaddition reaction starting from 3-substituted phenyl-5-((prop-2-yn-1-yloxy))methyl)isoxazoles and ( Z )-2-chloro- N -hydroxynicotinimidoyl chloride using NaHCO3 as an acid-binding agent in THF solvent-dissolved trace water under catalyst-free microwave-assisted conditions.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
ACS Materials Letters
·
2024
·
IF 9.6
Yuanhao Shen,Mingjun Qiu,Xiaocheng Huang,Weiwei Du,Xinlei He,Yingwu Luo,Zheng Yang,Junjie Zhao
Nonlithographic patterning of polymer thin films enables various applications spanning from soft electronics to biomedical engineering. Developing area-selective deposition (ASD) for polymers could achieve self-aligned polymer growth, fostering the generation of complex nanostructures and device configurations with enhanced precision and versatility. However, due to the rapid radical propagation in chain reactions, achieving area-selective radical polymerization in all-dry processes still represents a huge challenge. Here, we report a photocatalytic surface-initiated chemical vapor deposition method. Localized radical generation on the TiO2 surface enabled ASD of a poly(glycidyl methacrylate) (pGMA) thin film. Increasing hydroxyl groups and eliminating Ti(III) defects on the TiO2 surface by the O2 plasma pretreatment were found to be crucial to promote the photocatalytic initiation efficiency. Moreover, we obtained area selectivity of up to 92.2% on prepatterned TiO2/SiO2 substrates with pGMA film thickness over 10 nm on TiO2. Our work offers placement control over chain-growth polymers, providing new opportunities for bottom-up nonlithographic nanofabrication.
研究领域:
材料科学
·
高分子化学
·
纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）