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Macrocyclic Receptors Synthesis, History, Binding Mechanism: An Update on Current Status
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
Pillararenes are symmetrical macrocyclic receptors, where synthesis of these types of receptors requires a single synthetic step and hence can be easily accessible with higher synthetic yield. The condensation product of 1,4-dimethoxybenzene and paraformaldehyde in the presence of a Lewis acid catalyst produces the first pillararene as 1,4-dimethoxypillar[5]arene. The subsequent removal of methoxy groups using BBr3 (boron tribromide) yielded pillar[5]arene. Commonly used Lewis acid catalysts for pillararenes synthesis include ferric chloride (FeCl3), boron trifluoride (BF3), sulfuric acid (H2SO4), trifluoromethanesulfonic acid (CF3SO3H), trifluoroacetic acid (CF3COOH) and p-toluenesulfonic acid (PTSA).
Properties of the Elements and Inorganic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Bismuth tungstate Bismuth vanadate Bismuth zirconate Borane carbonyl Borazine Boric acid Boron Boron arsenide Boron carbide Boron nitride Boron oxide Boron phosphide Boron silicide Boron sulfide Boron tribromide Boron trichloride Boron trifluoride Boron trifluoride etherate Boron triiodide Bromic acid Bromine Bromine azide Bromine chloride Bromine dioxide Bromine fluoride Bromine monoxide Bromine pentafluoride Bromine trifluoride Bromoauric(III) acid pentahydrate Bromogermane Bromosilane Bromosyl trifluoride Bromotrichlorosilane Bromyl fluoride Cadmium Cadmium acetate Cadmium acetate dihydrate Cadmium antimonide Cadmium arsenide Cadmium azide Cadmium borotungstate octadecahydrate Cadmium bromide Cadmium bromide tetrahydrate Cadmium carbonate Cadmium chlorate dihydrate Cadmium chloride
Doping, Surface Modifications and Metal Contacts
Published in Andrew Sarangan, Nanofabrication, 2016
Liquid source dopants include boron tribromide (BBr3) and phosphoryl chloride (POCl3) [2,3]. The liquid is heated to increase its vapor pressure, and then bubbled with a carrier gas such as Ar, argon, nitrogen or oxygen to increase the flow rate and distribution of the vapor in the chamber, as illustrated in Figure 8.3. Although these liquid sources are still hazardous, they have significantly lower vapor pressures and are more contained than the gas phase dopant. They also offer the same flexibilities and advantages of gas sources.
Smart gas sensor based on photonic crystal for sensing perilous gases: industrial and mining applications
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Sathish Kumar Danasegaran, Elizabeth Caroline Britto, Poonguzhali S
The several existing PhC sensors are based on a single structure and can sense only a single gas. Also, the existing resonator structures were based on basic circular rods around the dielectric material and that sensor can detect only one gas. If the rod shape of PhC varies it tends to enhance the sensor performance. The novelty of the proposed work is the resonator structure is optimized for various shapes like square, rhombus, pentagon and hexagon. Further, the PhC sensor is designed with square and hexagonal Si rods and the sensor can detect seven toxic gases including Boron tribromide (BBr3), carbon monoxide (CO), cyanogen (CN)2, hydrogen cyanide (HCN) and phosgene (COCl2). The article’s organization in section 2 elucidates the PhC sensor principle and various PhC design resonator structures are discussed in section 3. In section 4, the simulated outputs are investigated and the paper is concluded in section 5.
Synthesis and properties of novel 6,7-dihydrocyclopenta[5,6-b]benzofuran-based liquid crystal compounds
Published in Liquid Crystals, 2021
Danyang Wan, Jian Li, Lingchao Mo Mo, Xiaozhe Yang, Zhaoyi Che, Minggang Hu, Juanli Li, Zhongwei An
Boron tribromide (5.0 mL, 51.9 mmol) was added dropwise to a solution of (±)-5-bromo-2-ethyl-6-methoxy-2,3-dihydro-1 H-indene (Compound G, 2.80 g, 11.0 mmol) and dichloromethane (30 mL) at −10°C~0°C. Then, the reaction system was stirred at room temperature for 2 hours before quenching with water (30 mL), extracted with dichloromethane (2*30 mL), washed with water (2*30 mL), and dried over anhydrous MgSO4. The inorganic salt was filtered off and the solvent was removed. The residue was purified by column chromatography on silica gel (eluent: n-heptane/dichloromethane, 1/1, V/V) to afford the desired product as a dark green solid (2.39 g, 90% yield). 1 H NMR (500 MHz, CDCl3): δ = 0.96 (t, J = 7.5 Hz, 3 H), 1.47–1.53 (m, 2 H), 2.33–2.39 (m, 1 H), 2.47–2.52 (m, 2 H), 2.93–2.98 (m, 2 H), 5.33 (s, 1 H), 6.85 (s, 1 H), 7.24 (s, 1 H) ppm. 13 C NMR (125 MHz, CDCl3): δ = 150.6, 145.5, 137.4, 127.3, 112.1, 107.6, 42.7, 39.0, 38.2, 28.6, 12.7 ppm. MS m/z (RI, %): 239.9 (M+, 100), 241. 9 (M++2, 98), 131.9 (68), 160.9 (60), 145.9 (44), 197.9 (36), 199.9 (35).
Highly efficient chirality inducers in nematic liquid crystals: synthesis of 7,7’-disubstituted 2,2’-methylenedioxy-1,1’-binaphthyls
Published in Liquid Crystals, 2019
Christian Kühn, Matthias Bremer, Peter R. Schreiner
As substituents we chose polarizable aromatic, sterically demanding and mesogenic groups, as well as substituents with polarizable units. Compounds 17a–g were prepared from 2-naphthols derivatives 1a–c. The racemic products were separated by HPLC on a chiral column and their helical twisting powers measured in the nematic mixture MLC-6260 (Merck KGaA, Darmstadt, Germany). 7-Methoxy-2-naphthol 1a was converted into 7- methoxy-2-trifluoromethane- sulfonyloxy - naphthalene 2. Palladium-catalyzed cross-coupling [30] of triflate 2 with organoboranes 3a (commercially available) and 6 (obtained from the bromo compound) afforded 7-methoxy-2,2ʹ-binaphthalene 4 and 2-(3,5-di-tert.-butylphenyl)-7-methoxy-naphthalene 7. Finally, ether cleavage of 4 and 7 with boron tribromide gave the desired 7-substituted 2-naphthols 5a and 5b.