Synthesis of MWCNT-COOH: Carboxylic acid-functionalized MWCNTs (MWCNT-COOH) were prepared following the literature [35]. Pristine MWCNTs were oxidized by a mixture of H2SO4/HNO3 at 70 °C for 3 h to prepare MWCNT-COOH. The resulting suspensions were then dialyzed for 3 days to remove all the salts and acids, and the purified MWCNT-COOH powder was collected by filtration and dried under vacuum. The MWCNT-COOH was redispersed in ethanol via sonication. Synthesis of OA-Fe3O4 NPs: OA-Fe3O4 NPs were prepared following the literature method [36]. For the synthesis of OA-stabilized Fe3O4 NPs, Fe(acac)3 (2 mmol), 1,2-hexadecanediol (10 mmol), oleic acid (5 mmol), oleylamine (6 mmol), and benzyl ether (20 mL) were mixed and magnetically stirred under …show more content…
For the synthesis of TOABr-stabilized Pd NPs with a diameter of ∼2.61 nm, an aqueous solution of 30 mM aqueous K2PdCl4 (30 mL) was first added to 25 mM TOABr in toluene (80 mL). Transfer of the K2PdCl4 from the aqueous phase to the toluene phase was observed within 1 min. A solution of 0.4 M NaBH4 (25 mL) was added to the reaction mixture. After 30 min, the separated aqueous phase was removed, and the toluene solution containing the reduced TOABr-Pd NPs was subsequently washed sequentially with 0.1 M H2SO4, 0.1 M NaOH, and H2O. Synthesis of Cationic-Pd NPs: Cationic Pd NPs were prepared as reported previously [32]. For the synthesis of cationic Pd NPs, an aqueous solution of 0.1 M 4-dimethylaminopyridine (DMAP) (80 mL) was added to the as-prepared TOABr-Pd NP toluene solution (80 mL). In this case, the Pd NPs were directly phase-transferred from toluene to the aqueous phase within 3 h, and the toluene phase was subsequently removed. The resulting Pd NPs were stabilized by cationic DMAP ligands in water (i.e., DMAP-Pd …show more content…
The solution was transferred to an autoclave, sealed, and maintained at 180 °C for 12 h, followed by washing with methanol. The OA-TiO2 NPs were isolated by centrifugation and dispersed in toluene. Synthesis of OA-Ag NPs: For the preparation of OA-stabilized Ag NPs [39], silver trifluoroacetate (0.4 g), OA (3.5 mL), and isoamyl ether (30 mL) were mixed in a 250 mL three-neck flask under argon. The mixture was heated at 160 °C for 30 min then cooled to room temperature by removing the heat source. The purification process was performed four times using excess polar solvent (ethanol) and centrifugation. The precipitated OA-Ag NPs were dispersed in
When the red Co(NO3)2*6H2O crystal was added to the white NH4 crystal, and water was added to dissolve, the solution turned blue in color. As the solution was nixed, the color changed to that of a blue-purple and a blue precipitate formed. When the 6 M NH3 began to be added, the color shifted to dark purple color after 15 mL of ammonia and the amount of the precipitate was less. After 20 mL of ammonia, the solution became a red brown with very little of the blue precipitate. After 30 mL of ammonia, the solution was similar in color to an iodine solution, a dark brown-red, almost black in color. At this point there was no visible precipitate on the surface of the solution. After 40 mL of the ammonia had been added, the solution was the same iodine like color as before. When closely examined, there was a black precipitate that had settled on the bottom of the beaker. At this point, hydrogen peroxide, 3% H2O2, was added to solution. After 4 mL of the H2O2 was added, the solution was the same color and the precipitate had not changes. After 8 mL of the H2O2, there was not noticeable change. After 12 mL of the H2O2, the solution was slightly redder in color but the precipitate had not changed. After 15 mL of H2O2, the solution was the same color and no changes had occurred to the precipitate. At 17 mL, the solution began to effervesce slightly, though there
Isoamyl acetate was synthesized by refluxing 1 eq of isopentanol with 4 eq of acetic acid, and 0.5 eq of concentrated sulfuric acid as a catalyst and a dehydrating agent to ensure reaction equilibrium lies far towards the products. The reaction mixture was then added to water and liquid-liquid extraction was conducted. A second extraction was then conducted after adding NaHCO3 solution to the organic layer. This removes the residual acids which are soluble in the aqueous layer. Drying of the crude ester with anhydrous MgSO4 removes H2O that disrupts the NMR and infrared spectrum, hindering the characterization of the product formed.
The goal of this was to successfully accomplish the synthesis of para-Chlorophenoxyacetic acid. In this experiment, para-Chlorophenoxyacetic acid was synthesized from 4-chlorophenolate and chloroacetic acid using an SN2 reaction. The product obtained was determined to be the para isomer of Chlorophenoxyacetic acid. This was confirmed by the melting point of 157.3-157.9 ◦C. The percent yield determined at the end of the experiment was 37.83 %. The TLC analysis showed that P-Chlorophenol was less polar than P-Chlorophenoxyacetic Acid because it had an Rf value of 0.38 in comparison to the value of 0.33 on a 50:50 hexane and ethyl acetate solvent mixture. In the NMR comparison, it was shown that both the starting material of chloroacetic acid and product contained a peak of integration two around 4 ppm representing the acidic proton. In the FT-IR comparison, it was determined that the Chloroacetic acid and the para-Chlorophenoxyacetic acid both had an OH bond at 3416 cm-1 and 3429.72 cm-1 respectively. The Chloroacetic acid and para-Chlorophenoxyacetic acid also both had a carbon-oxygen double bond at 1648 cm-1 and 1654.81 cm-1 respectively. The para-Chlorophenoxyacetic acid also contained a peak at 1236.18 cm-1 which represents the C-O-C bond.
Furthermore, the principles and metrics of green chemistry were incorporated into the synthesis reaction through the use of the benign solvent, water. Through the use of the vacuum filtration and the recrystallization procedures, the product was further purified. Subsequently, the purity and identity of the product were evaluated through the analysis tool of Nuclear Magnetic Resonance. Ultimately, the efficiency and greenness of the reaction were measured through the calculation of the percent yield and the atom
Nanocrystals are made up of drug with only little amount of surfactant (below critical micelle concentration (CMC)) to stabilize formulation [14]. Most of the nanoparticles are made up of large amount of excipients which is not the case with nanocrystals as most of the part is only the drug. Besides lower amount of stabilizers makes toxicity issues associated with nanosuspensions negligible and offers ease of scale-up and better physical stability compared to amorphous form [15, 16]. Different methods are classified as top-down (high pressure homogenization, media milling, and sonication) and bottom-up techniques (nanoprecipitation) for effective production of Nanocrystals [17]. Development of nanocrystal based formulation of risperidone can be advantageous to tackle the problem of poor water solubility. Numerous solidification techniques are used to increase physical stability of nanosuspensions as spray drying, lyophilization and many more based upon the properties of drug and characteristics of final formulation. Amongst all these techniques lyophilization is used predominantly for nanosuspension solidification.
Procedure: In the first experiment (Synthesis Reaction) 5g of Mg was heated with a Bunson burner to perform a reaction. In the second experiment (Decomposition Reaction) 5g of Cu2Co3 was heated with a Bunson burner to perform a chemical reaction with visible physical properties. In experiment 3 (Single Displacement Reaction) 15 mL of 6 M hydrochloric acid (HCl) was put into a Erlenmeyer flask and was stopped with an airtight stopper to record the temperature and pressure when .25g of Zinc was added. In Experiment 4 (Double Displacement Reaction) two separate beakers were used. In the first one there was 15mL of NaOH and the second contained NiCl2. These were poured into each other to watch what reaction would take place.
Compound 4 was then used to create the intermediate compound 6 using an N-iodosucciminide-mediated (NIS) nucleophilic displacement with dibenzyl phosphate in dichloromethane and THF exposed to 4 Å molecular sieves. This method resulted in a yield of 91% of compound 6. A sequence of extractions used to purify compound 6 further, which is described in the Materials and Methods section of this paper. This procedure allows for the production of compound 6 to be scaled up and well as obtain efficient
Nevertheless, our initial attempts with the reported procedure to isolate the intermediate were proven futile and low yielding due to high reactivity and instability of the intermediate. To circumvent this problem, I revised the synthesis under one-pot reaction condition without the need for the isolation of the intermediate. Activation of the protected guanosine with 1.2 equivalent of the chloroformate and subsequent addition of an excess amount of the tryptamine (4 eqvi) resulted in the coupled product. Isolation and deprotection of the coupled product resulted in the final product with more than 70% yield. Next, we investigated the effect of TrpGc on the activity of hHint1 using a fluorescence assay described previously.3 At a fixed saturating substrate concentration, TrpGc exhibited a dose dependent decrease in the activity of hHint1 with maximum half inhibitory concentration (IC50) values of 25.5 ± 6.0 μM (Fig 1). We next employed isothermal titration calorimetry (ITC) to investigate the nature of non-covalent interactions on the inhibitory activity of Bio-AMS on hHint1. The ITC studies provided an experimental dissociation
4-(2-aminoethyl)morpholine (742 mg, 5.7 mmol) and acetone (10 mL) were mixed together on ice, while a mixture of 4-chlorobenzoyl chloride (0.55 ml, 4.3 mmol) in acetone (2.5 mL) was added drop-wise for 10 minutes. Then, the mixture was mixed on ice for an addition five minutes, then for ten minutes at room temperature. Diethyl ether (10 mL) was added to the mixture and the resultant white precipitate was filtered. The product was recrystallized using ethanol (95%) and filtered. After drying, the crystals were dissolved in a mixture of dichloromethane (10 mL) and ammonia (concentrated, 10 mL). The organic layer was removed and the aqueous layer was washed with dichloromethane (10 mL). The combined organic layer was dried with sodium sulfate (anhydrous) and evaporated, which afforded a white powder (0.68 g, 66%) mp: 130-133°C; 1H NMR (400 MHz, CDCl3) δ (ppm) 7.71 (d, 2H), 7.41 (d, 2H), 6.87 (s, 1H), 3.73 (t, 4H), 3.53 (q, 2H), 2.60 (t, 2H), 2.5 (t, 4H); IR (ATR) υmax (cm-1) 3277, ~2900, 1633, 1595, 1546, 1486, 1469, 1461, 1142, 1116,
M.p. 200-201 oC. 1H NMR (300 MHz, DMSO, ppm): δ 1.20 (t, 3H, J ¬= 7.1 Hz, COOCH¬2¬CH¬3), 1.31 (t, 3H, J¬ = 7.1 Hz, COOCH¬2¬CH¬3), 2.77 (t, 2H, J ¬= 5.6 Hz, H-4), 3.59 ( t, 2H, J = 5.1 Hz, H-5), 4.08 (q, 2H, J¬ = 7.0 Hz, COOCH¬2-CH¬3), 4.29 (q, 2H, J¬ = 7.0 Hz, COOCH¬2¬CH¬3), 4.45 (s, 2H, H-7). 8.55 (s, 2H, NH2), 11.42 (s, 1H, NH). 13C NMR (75 MHz, DMSO, ppm): δ 13.8 (CH3), 14.3 (CH3), 25.7 (C-4), ¬40.6 (C-5), 41.9 (C-7), 60.2 (CH2, ester), 60.7 (CH2, carbamate), 110.5 (C-3), 121.8 (C-3a), 128.4 (C-7a), 151.0 (C-2), 154.5 (C=O), 165.0 (C=O, carbamate), 178.7 (C=S). Anal. Calcd for C14H19N3O4S2 (357.45): C, 47.04; H, 5.36; N, 11.76; Found C, 46.91; H, 5.19; N,
To a solution of o-aminoester 1 (0.9 g, 3 mmol) in DMSO (5 mL), carbondisulfide (0.3 mL), saturated sodium hydroxide (0.2 mL) and dimethyl sulfate (0.5 mL) were added. The mixture was stirred overnight (TLC showed complete conversion). The precipitate that formed was filtered off, washed with ethanol and crystallized from methanol to give compound 3 as yellow crystals (0.72 g, 62%); mp: 168-169oC; 1H-NMR (400 MHz, DMSO-d6): δ 1.21 (t, 3H, J ¬= 7.1 Hz, COOCH¬2¬CH-3), 1.32 (t, 3H, COOCH¬2¬CH¬3), 2.80 (s, 3H, CH¬3), 2.82 (t, 2H, J ¬= 6.5 Hz, H-4), 3.62 (t, 2H, J¬ = 6.5 Hz, H-5), 4.03 (q, 2H, J = 7.2 Hz, COOCH¬2¬CH¬3), 4.08 (bs, 1H, NH), 4.30 (s, 2H, H-7), 4.53 (q, 2H, J = 7.2 Hz, COOCH¬2¬CH¬3); 13C-NMR (100 MHz, DMSO-d6): δ 14.2 (CH3), 22.8 (C-4),
To the 1.31 g (2.7 mmol) of compound 2, in 6 mL EtOH in a round bottom flask, (2mL) NaOH 2M was added drop wise. The reaction mixture was stirred for overnight. Then 5 mL of distilled water was added to the reaction mixture and solvent was removed under reduced pressure. The residue was washed with diethyl ether (2 x 30 mL). Then it was cooled down under ice-water bath for 10 minute and then pH was adjusted to 1 by drop wise addition of 1 M HCl. Then ethyl acetate (50 mL) was added and filtered off. The filtrate was washed with sodium carbonate solution to yield compound 3 as a white solid. FT-IR (KBr) νmax/cm-1: 3440, 3288, 3176, 2978, 1706, 1641, 1571, 1453, 1413, 1339, 1053,
The Diels-Alder step is the “bottleneck” of previous synthetic strategies due to its wasteful reaction and low yield. Our synthetic strategy was able to produce the scaffold using the Diels-Alder reaction and high yield. This is due to the added solubility of the non-functional anthracene. Unfortunately, our total yield is lowered due to the alkylation of the scaffold. Reproducing the 98% yield will further increase our total yield and goal. In the future, optimizing the alkylation step is necessary to reach the previously reported yield. The next step in the synthesis is brominating the scaffold, which will allow different functional groups to be added using metal catalysis. Sonagashira will be used to add different functional groups. Since our strategy allows us to add functionality at the end with no “bottleneck” reaction, Pentiptycene can be synthesized in higher quantity without wasting material. Optimizing this synthesis will further the study of pentiptycene as novel material for molecular machinery, polymers, and porous
The purpose of this lab is to find the oxidation state of manganese for the synthesis of manganese (?) chloride, and to complete the naming of the compound. The discovery of the charge of manganese in the ionic compound will be used to further the analysis of the reaction. The lab requires performing the chemical reaction of synthesizing manganese metal and hydrochloric acid. The laboratory techniques required to find the oxidation state will include qualitative observation, collecting quantitative data, gravimetric analysis, unit conversions, and stoichiometry.
After this we added .5g of NaCl and allowed the solution to cool to room temperature then placed it into an ice bath. The reaction mixture turned into a lighter shade of yellow and began to crystallize. The crystals were filtered through a Buchner funnel and rinsed twice with saturated aqueous NaCl solution. The reaction mixture was placed in a boiling water bath in order to dissolve most of the dye and all the contaminating salts. It was then cooled in a ice bath and filtered using a Buchner funnel. The product obtained was shiny and a metallic gray-gold color. The product weighed in at .207g of methyl orange, giving us a percent yield of