Arginine Ester Hydrochloride Lab Report

The light yellow precipitate was collected by suction filtration using a Hirsch funnel. The product was washed with two 1-mL portions of cold methanol followed by two 1-mL portions of diethyl ether. The product was dried in the oven at 110°C. The IR spectrum as a KBr pellet was obtained for the product and inosine for analysis.

In the primary ligand structure two methyls were stayed in meta state and the hydrogen of phenol was omitted.

In order to improve the reaction efficiency, reaction time was increased from 1h to 2h, which led to the drop of the desired product yield (however, yield of 2a decreased to 35%) (entry 4). Then, we examined the effects of increasing amount of TBHP and TBAB at reaction temperature of 80 °C for improving the reaction efficiency (entries 5-7) and the best result observed when, 50 mol%. TBAB and 8.0 equiv. TBHP were used (entry 7). Also, other additives such as TBPB, Aliquat 336, KI, CuI and element iodine (I2) were used. Tetrabutylphosphonium bromide (TBPB) and Aliquat 336 gave the corresponding product 3a in 75% and 48% yields, respectively (entries 8 and 9) and KI, CuI as well as element iodine (I2) were ineffective to the CDC reaction (entries 10-12). Notably, no product was detected when, K2S2O8 and H2O2 as the oxidants were employed instead of TBHP (entries 13 and 14). In addition, The solvent screening studies indicated that no product was formed in the solvents such as PhCl, CH3CN, 1,4- dioxane and DMSO (entries 15-18). We also carried out a reaction without solvent of toluene (or under neat), led to the formation of product 3a with 40% yield (entry 19). In the absence of TBAB as additive (entry 20), 2a was not detected, which suggested that TBAB played the important role in this

Aniline derivatives (4 mmol) or 1,8-diaminonaphthalene derivative will dissolved in 20 mL hydrochloric acid (1 M) and stirred with magnetic stirrer for one hour. 20 mL hydrochloric acid (1 M) will be used to dissolve ammonium persulfate (4 mmol) and magnetically stirred for one hour. Then the ammonium persulfate solution will be added into the aniline derivative or 1,8-diaminonaphthalene derivative solution and will be left at room temperature for 6-9 hours. Finally, the precipitate will be collected and washed several times by acetone and distilled water. The obtained compounds (pure polyanilines or polynaphthylamines) will be dried at ambient temperature for 24

L. Zhu et. al., reported the synthesis of new derivatives of 4-aryl-3,5-dicyano-2,6-di(3′-indolyl)pyridine (50) and polysubstituted (3′-indolyl)pyrazolo[3,4-b]pyridine and (3′-indolyl)benzo[h]quinolines (51) via a one-pot multicomponent reaction of aromatic aldehydes, 3-cyanoacetyl indoles, and ammonium acetate employing the microwave irradiation as an energy source and ethylene glycol as a solvent,115,116 scheme 50.

5-nitro-2,3-dihydroxydrophthalazine-1,4-dione was measured to 0.140 grams. 2ml of NaOH was added to the concial vile which turned the mixture rustic in color. Sodium hydrosulfate was measured to 0.2506 grams and added to the conical vile. The mixture became an even deeper red. 0.5 ml of water was then used to wash all the solid from the vile walls. As the conical was spun, white chunks were visible, so the heat was increased to a level of six rather than 5. After adding acetic acid, there was an orange layer that formed. There was a yellow layer on top of the orange layer. After stirring the conical vile, the mixture turned opaque and stayed orange. One the conical vile was cooled on ice for 10 minutes, the mixture became lighter.

HCl)33, respectively, with 2-mercaptoacetic acid (2) in the presence of 6M hydrochloric acid under reflux for 4 hours in 70% yield. 1H-NMR spectrum of 3a , as an example, showed a singlet at 1.7 for SH, singlet at 3.8 for methylene group and benzimidazole protons at 7.4 and 7.6 ppm. Compounds 3a and 3b were heated with 2,2-dichloroacetic acid (4) and potassium carbonate in absolute ethanol under reflux for 3 hours to give 2,2-bis(((1H-benzo[d]imidazol-2-yl)methyl)thio)acetic acid (5a) in 69% yield and 2,2`-bis(((5-hydroxy-1H-benzo[d]imidazolyl)methyl)thio)acetic acid (5b) in 66% yield, respectively. Compounds 5a,b gave compatible spectroscopic data (Experimental). Condensation of o-phenylenediamine (1) with each of 5a,b in the present of 6N hydrochloric acid give 2,2`-((((1H-benzo[d]imidazol-2-yl)methylene)bis(sulfane-diyl))bis-(methylene))bis-(1H-benzo[d]imidazole(6a) in 66% yield, and2,2`-((((1H-benzo[d]imi-dazol-2-yl)bis(sulfane-diyl)bis(methylene))-bis(1H-benzo-d]imidazol-5-ol) (6b) in 61% yield; Scheme (1).

The boiling points recorded for both compounds were slightly off due to an error while performing the lab. The thermometer was set too low to the vigrex column, resulting in lower boiling points. This can be fixed by raising the thermometer in the stillhead to height of where the glassware splits. Even with this discrepancy, the identity of both compounds was still confirmed. For fraction A, the IR RM-03-IRA was obtained. This spectrum contains a peak at 2877 cm-1 and a peak at 1106 cm-1. The second peak shows that the compound contains an ether. The presence of this functional group and the lack of a carbonyl group and hydroxyl group eliminated 9 of the 13 possible unknowns. The NMR spectra eliminated the other three possibilities. The NMR spectra obtained for fraction A are RM-03-NMRA1 and RM-03-NMRA2. The 1H NMR, RM-03-NMRA1, showed only 2 types of protons present, one represented at 3.47 ppm and the other at 3.32 ppm. It also showed that there was acetone in the NMR tube by the presence of the peak at 2.09 ppm. There were only two compounds left that had two types of protons, 1,2-dimethoxtethane and

All reagents were of the highest quality available and were purchased either from Sigma Aldrich, Merck, Fluka, Scharlau Chemie, Roth, CALEDON, Gibco, Invitrogen or Biofil. N,N,N',N'-Tetramethyl-O-(benzotriazol-l-yl)Uronium Tetrafluoroborate (TBTU), Triisopropylsilane (TIS), 1-hydroxybenztriazole (HOBt), 5(6) Carboxyfluorescein (FAM), Potassium cyanide, Methotrexate and Ninhydrine were obtained from Sigma-Aldrich (St. Louis, MO, USA). 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide (MTT) was from Roth (Karlsruhe, Germany). Piperidine was obtained from BDH Laboratory Supplies (England). Trifluoroacetic acid (TFA) was from Fluka (Buchs, Switzerland). N-ethyldiisopropylamine (DIPEA), Triethylamine (TEA), Dimethyl Sulfoxide (DMSO), Acetonitrile

p-Dimethylaminobenzaldehyde (1g) and rhodanin-N-acetic acid (1.25g) were dissolved in ethanol (50 ml). The mixture was stirred thoroughly for a few minutes. The temperature was raised to 800C and the mixture was refluxed for 4 hours. The product was filtered. It was purified by recrystallisation from absolute ethanol. The yield was noted as 80%. It was further purified by column chromatography using 10:3 hexane-ethyl acetate solvent systems and dried in vacuum. The reaction s showing the synthesis of the products are shown in table 3.1

In part 1, around 1.5 g of p-aminophenol was weighted and added into 100 mL Erlenmeyer flask and then placed on a steam bath. While the flask was being heated, 1 mL of water: ethanol (1:1) was added continuously until p-aminophenol was dissolved. The flask was let to cool down at room temperature until crystals started to form, then the flask was placed into an ice bath. The compound was filtered using a vacuum filtration apparatus and a Buchner funnel until crystals were dried. Formed compound was weighted and 10 g was kept for later use. Recrystallised p-aminophenol was placed into a 100 mL Erlenmeyer flask and 9 mL of water

This reaction is divided into two parts. In the first part acetone, L – proline and 4 – nitrobenzaldehyde are reacted to give (R)-4-hydroxy-4-(4-nitrophenyl)butan-2-one as the major product along with (S)-4-hydroxy-4-(4-nitrophenyl)butan-2-one. The identity of the product is confirmed by IR spectra of the product which gives peaks at 1073.94 cm-1, 1330 cm-1, 1515.05, 1600.13 cm-1, 1708.25 cm-1, 2930.82 cm-1and broad peak at 3418.10 cm-1. The mass of the product is 0.013 grams which gives a percentage yield of 29.81%. The melting point of the product is not taken due to minimal product.

The product obtained after reflux was a yellow liquid. With the halide tests, the product reacted faster with sodium iodide to form a precipitate than with silver nitrate. This indicates that the degree of the product was primary and that bromine did replace the alcohol group. The IR of the product showed four peaks at 3326.36, 2932.86, 1465.34, and 1028.73. These peaks indicate O-H, C-H, C-H3, and C-O bonds, respectively, within the product. 2.032 grams of product were recovered from the reaction. With this, a percent yield of 27.14% was calculated.

The formation of the imine is carried out by adding 0.213 grams of ortho-vallin, the aldehyde, and .150 grams of para toluidine. The solids were grinded until homogenous, one layer is formed. The crystals went from brown to orange liquid layer. The bi-product of imine formation is water, and OH gets protonated and come off during the reaction. Recrystallization is done to get rid of water. Hexane is used as the recrystallization solvent because it is non-polar, like the imine. The mass is 0.3365 grams and the percent yield is 99.6%. There was some product lost on the stirring rod. The IR showed a peak at 2942.40 indicating a methyl group and a peak at 1593.67 and 1614.90

The final yield for this compound was 0.01 or 1%, mainly because of human errors. Possibly, the starting reactants may have been incorrectly mixed or mixing temperature could have been exceeded. Other plausible error might have been incorrect use of separating funnel or reflux condenser. Overall yield cannot be calculated due to a fact that no other measurements took place during this experiment to help determine the overall yield. To increase the final and overall yields, the starting reagents should be mixed properly, separating funnel should be used with great care and laboratory schedule provided should be followed.