Synthesis Of 4-Bromobutyrate

The crude product was washed by taking the reaction product in the separatory funnel and adding 23 mL of deionized H2O. The mixture was shaken and allowed to settle until layers were observable. The top layer was the desired product and approximately 25 mL of aqueous layer was extracted from the separatory funnel. Next, 25 mL of 5% NaHCO3 was added to the separatory funnel in order to neutralize the acid. This mixture was swirled, plugged with the stopper and inverted. Built-up gas was released by turning the stopcock to its opened and closed positions, releasing CO2 by-product. This was done four times in one minute intervals. The solution was allowed to settle until layers were observable. The bottom layer that contained salt, base and water was extracted from the separatory funnel. The crude product was washed again as mentioned previously.

9-anthraldehyde and (carbethoxymethylene)triphenylphosphorane were reacted together using the Wittig reaction to produce E-3-(9-Anthryl)-2-propenoic acid ethyl ester. .100 g of 9-anthraldehyde and .180 g of (carbethoxymethylene)triphenylphosphorane were used. 9-anthraldehyde was a green powder while (carbethoxymethylene)triphenylphosphorane was a white powder. Both were added together into a 3.00 mL conical vial with a magnetic spin valve. The vial was inserted into a 120 C sand bath to melt the reagents. Once the reagents melted, they were stirred for 15 minutes (2:30 pm-2:45 pm). After stirring, the vial was removed to cool to room temperature. 3.00 mL of hexanes were added to the vial and the suspension was stirred. The solvent was removed

Preparation of 1 required the alcohol starting material (3.50 g, 0.023 mol) and sodium bromide (2.88 g, 0.028 mol) to be added to 5 mL of 9M H2SO4 and heated very carefully, due to its high boiling point, under standard reflux conditions for 25 m. While under reflux, the reaction developed two layers; a top reddish layer and a bottom clear layer. Following reflux, the resulting reaction material was allowed to cool and liquid material was pipetted away from excess NaBr solid. Extraction of the collected material with 1 x 15 mL of water and 2 x 10 mL of 5% NaHCO3, followed by drying with sodium sulfate, gave the oil 1 (3.68 g, 0.017 mol, 75%). 1H NMR (CDCl3, 200 MHz) 7.6-7.0 (m, 4H), 3.51 (t, 2H), 2.62 (t, 2H), 2.34 (s, 3H), 2.12 (p, 2H). IR (cm-1) 3106, 3087, 2968, 1951, 1882, 1806, 1496, 1454, 1227, 1069, 758.

Reaction 1 involved a primary alcohol (OH), weak leaving group in the starting material and a reaction with a strong nucleophile (sodium bromide) and a polar protic solvent (sulfuric acid). The reaction was carried out through reflux and the product had a relatively high yield (75%) (Scheme 1).

The mixture was heated at 120°C using an aluminum block and was stirred gently. After all of the solid dissolved, it was heated for 20 additional minutes to ensure the reaction was complete.

In the first reaction, trans-stilbene was brominated to give meso-stilbene dibromide. In the second reaction, the stilbene dibromide was heated with base to induce dehydrobromination (net loss of HBr) and formation of diphenylacetylene. The purpose of this lab experiment is to carry out the bromination of E-stilbene and characterize the product, meso-stilbene dibromide, by its melting point. In the following experiment, the dibromide is converted into diphenylacetylene. Pyridinium hydrobromide perbromide (PHPB), a crystalline solid which is much less corrosive and easier to handle than liquid bromine was the brominating agent used in this

(2) Scheme 2: Synthesis of and Isolation of Benzoic Acid The above reaction was carried out and was unsuccessful, yielding almost no amount of product. The desired appearance of the product was a white crystalline compound. Since barely any product was isolated benzoic acid in the lab was substituted for the next reaction.

Discussion: In the synthesis of 1-bromobutane alcohol is a poor leaving group; this problem is fixed by converting the OH group into H2O, which is a better leaving group. Depending on the structure of the alcohol it may undergo SN1 or SN2. Primary alky halides undergo SN2 reactions. 1- bromobutane is a primary alkyl halide, and may be synthesized by the acid-mediated reaction of a 1-butonaol with a bromide ion as a nucleophile. The proposed mechanism involves the initial formation of HBr in situ, the protonation of the alcohol by HBr, and the nucleophilic displacement by Br- to give the 1-bromobutane. In the reaction once the salts are dissolved and the mixture is gently heated with a reflux a noticeable reaction occurs with the development of two layers. When the distillation was clear the head temperature was around 115oC because the increased boiling point is caused by co-distillation of sulfuric acid and hydrobromic acid with water. When transferring allof the crude 1-bromobutane without the drying agent,

+ HEAT The product N-acetyl anthranilic acid was synthesized through the reaction of anthranilic acid with acetic anhydride, which was hydrolyzed leading to the formation of the white crystalline product. The reaction of anthranilic acid with acetic anhydride lead to acetylation of the amino group.

The goal of this experiment was to synthesize aspirin. In this experiment aspirin, also known as acetylsalicylic acid, was synthesized from salicylic acid and acetic anhydride. In the reaction the hydroxyl group on the benzene ring in salicylic acid reacted with acetic anhydride to form an ester functional group. This method of forming acetylsalicylic acid is an esterification reaction. Since this esterification reaction is not spontaneous, sulfuric acid was used as a catalyst to initiate the reaction. After the reaction was complete some unreacted acetic anhydride and salicylic acid was still be present in the solution as well as some sulfuric acid, aspirin, and acetic acid. Crystallization, which uses the principle of

The ether extracts is rinse twice with 10mL of water and dry over K2CO3. 7) Transfer the dried and filtered solution to oil after evaporate and rinse into a 50 mL Erlenmeyer flask. B: Synthesis of α-Chloro-2,6-dimethylacetanilide 1) Add 50mL of glacial acetic acid and 7.2 g (or 5.2 mL) of chloroacetyl chloride to every 7 grams of dimethylaniline from the previous step. 2) Warm the solution on a water bath at (40–50)ºC. After remove, add 1 gram of sodium acetate in 100 mL of water. 3)

Abstract: Synthesis of new compounds 2-(bis((1H-benzo[d]imidazol-2- yl)methylthio)methyl)-1H-benzo[d]imidazole (6a) and 2-((((1H-benzo[d]imidazol-2-yl)(((5- hydroxy-1H-benzo[d]imidazol-2-yl)methyl)sulfanyl)methyl)sulfanyl)methyl)-3H- benzo[d]imidazol-5-ol (6b) were carried out under two different reaction conditions, namely the conventional method and microwave irradiation conditions. The compounds (3a,b), (5a,b) and (6a,b) were synthesized by using microwave methods which showed decrease in the reaction time and increasing in the yield as shown in Table (1). The structures of the synthesized compounds were confirmed by IR; NMR and elemental analysis. The antimicrobial activityof the synthesized benzimidazolemethanethiol derivatives

The reaction began with the insertion of magnesium into the carbon-bromine bond to generate the Grignard reagent. 96 mg of magnesium turnings were ground up with a mortar and pestle in order to remove any surface oxides and contaminations that may preclude magnesium’s ability to react with unreactive alkyl halides. The magnesium turnings, along with a small crystal of iodine and a drop of 1,2-dibromoethane were added to a round bottom flask. The 1,2-dibromoethane is necessary to activate the alkyl halide. In a conical vial 2mL of anhydrous ether

In the materials and methods section; ligand preparation, target protein identification and preparation, molecular descriptors calculation, ADME (Absorption, Distribution, Metabolism and Excretion) and TOPKAT (Toxicity Prediction by Komputer Assisted Technology) analysis were carried out according to the previously reported method as briefly stated below.

Finally, Godwin et al.,9 has developed novel mono-sulfone chemistry that allows controlled conjugation of PEG to proteins and peptides. A component of this chemistry involves reduction by sodium borohydride to reduce the electron withdrawing carbonyl to prevent unwanted retro-Michael reactions. The mild reducing nature of this procedure allows selective cysteine modifications to be performed on native proteins without denaturation or racemization. Through a comparative study, PEG-mono-sulfone reagents demonstrated higher stability than