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Although this drug is categorized as a local anesthetic, I have chosento put it in with the hallucinogens because of the psycho- tomimeticeffects that it produces. Cocaine is not a phenylethyl- amine, but it produces central nervous system arousal or stimulant effects which closely resemble those of the amphetamines, the methylenedioxyamphetamines in particular. This is due to the inhibition
by cocaine of re-uptake of the norepinepherine released by the adrenergic nerve terminals, leading to an enhanced adrenergic stimulation of norepinephrine receptors. The increased sense of well being and intense, but short lived, euphoric state produced by cocaine requires frequent administration.

Cocaine does not penetrate the intact skin, but is readily absorbed from the mucus membranes, creating the need to snort it. This accounts for the ulceration of the nasal septum after cocaine has been snorted for long periods.

The basic formula for cocaine starts by purchasing or making tropinone, converting the tropinone into 2-carbomethoxytropinone (also known as methyl-tropan-3-one-2-carboxylate), reducing this to ecgonine, and changing that to cocaine. Sounds easy? It really is not very simple, but with Reagan's new drug policies, cracking down on all of the drug smuggling at the borders, this synthetic cocaine may be the source of the future. This synthesis is certainly worth performing with the high prices that cocaine is now commanding. As usual, I will start with the precursors and intermediates leading up to the product.

Succindialdehyde. This can be purchased, too. 23.2 g of succinaldoxime powder in 410 ml of 1 N sulfuric acid and add dropwise with stirring at 0¡ a solution of 27.6 g of sodium nitrite in 250 ml of
water over 3 hours. After the addition, stir and let the mixture rise to room temp for about 2 hours, taking care not to let outside air into the reaction. Stir in 5 g of Ba carbonate and filter. Extract the filtrate with ether and dry, evaporate in vacuo to get the succindialdehyde. This was taken from JOC, 22, 1390 (1957). To make succinaldoxime, see JOC, 21, 644 (1956).

Complete Synthesis of Succindialdehyde. JACS, 68, 1608 (1946). In a 2 liter 3 necked flask equipped with a stirrer, reflux condenser, and an addition funnel, is mixed 1 liter of ethanol, 67 g of freshly distilled pyrrole, and 141 g of hydroxylamine hydrochloride. Heat to reflux until dissolved, add 106 g of anhydrous sodium carbonate in small portions as fast as reaction will allow. Reflux for 24 hours and filter the mixture. Evaporate the filtrate to dryness under vacuo. Take up the residue in the minimum amount of boiling water, decolorize with carbon, filter and allow to recrystallize in refrigerator. Filter to get product and concentrate to get additional crop. Yield of succinaldoxime powder is a little over 40 g, mp is 171-172¡.

5.8 g of the above powder is placed in a beaker of 250 ml capacity and 54 ml of 10% sulfuric acid is added. Cool to 0¡ and add in small portions of 7 g of sodium nitrite (if you add the nitrite too fast, nitrogen dioxide fumes will evolve). After the dioxime is completely dissolved, allow the solution to warm to 20¡ and effervescence to go to completion. Neutralize the yellow solution to litmus by adding small
portions of barium carbonate. Filter off the barium sulfate that precipitates. The filtrate is 90% pure succindialdehyde and is not purified further for the reaction to create tropinone. Do this procedure
3 more times to get the proper amount for the next step, or multiply the amounts given by four and proceed as described above.

Take the total amount of succinaldehyde (obtained from 4 of the above syntheses combined) and without further treatment or purification (this had better be 15.5 g of succindialdehyde) put into an Erlenmeyer flask of 4-5 liters capacity. Add 21.6 g of methylamine hydrochloride, 46.7 g of acetonedicarboxylic acid, and enough water to make a total volume of 2 liters. Adjust the pH to 8-10 by slowly adding a saturated solution of disodium phosphate. The condensate of this reaction (allow to set for about 6 days) is extracted with ether, the ethereal solution is dried over sodium sulphate and distilled, the product coming over at 113¡ at 25 mm of pressure is collected. Upon cooling, 14 g of tropinone crystallizes in the pure state. Tropinone can also be obtained by oxidation of tropine with potassium dichromate, but I could not find the specifics for this operation.

2-Carbomethoxytropinone. A mixture of 1.35 g of sodium methoxide (this is sodium in a minimum amount of methanol), 3.5 g of tropinone, 4 ml of dimethylcarbonate and 10 ml of toluene is refluxed for 30 min. Coo] to 0¡ and add 15 ml of water that contains 2.5 g of ammonium chloride. Extract the solution after shaking with four 50 ml portions of chloroform, dry, evaporate the chloroform in vacuo. Dissolve the oil residue in 100 ml of ether, wash twice with a mixture of 6 ml of saturated potassium carbonate and three ml of 3 N KOH. Dry and evaporate in vacuo to recover the unreacted tropinone. Take up the oil in a solution of aqueous ammonium chloride and extract with chloroform, dry, and evaporate in vacuo to get an oil. The oil is dissolved in hot acetone, cool, and scratch inside of flask with glass rod to precipitate 2- carbomethoxytropinone. Recrystallize 16 g of this product in 30 ml of hot methyl acetate and add 4 ml of cold water and 4 ml of acetone. Put in freezer for 2l/2 to 3 hours. Filter and wash the precipitate with cold methyl acetate to get pure product.

Methylecgonine. 0.4 mole of tropinone is suspended in 80 ml of ethanol in a Parr hydrogenation flask (or something that can take 100 psi and not react with the reaction, like stainless steel or glass). 10 g of Raney Nickle is added with good agitation (stirring or shaking) followed by 2- 3 ml of 20% NaOH solution. Seal vessel, introduce 50 psi of hydrogen atmosphere (after flushing vessel with hydrogen) and heat to 40-50¡. After no more uptake of hydrogen (pressure gauge will hold steady after dropping to its lowest point) bleed off pressure and filter the nickle off, rinse out bottle with chloroform and use this rinse to rinse off the nickle while still on the filter paper. Make the filtrate basic with KOH after cooling to 10¡. Extract with chloroform dry, and evaporate the chloroform in vacuo to get an oil. Mix the oil plus any precipitate with an equal volume of dry ether and filter. Add more dry ether to the filtrate until no more precipitate forms, filter and add to the rest of the precipitate. Recrystallize from isopropanol to get pure methylecgonine. Test for activity. If active, skip down to the step for cocaine. If not active, proceed as follows. Stir with activated carbon for 30 min, filter, evaporate in vacuo, dissolve the brown liquid in
methanol, and neutralize with 10% HCI acid in dry ether. Evaporate the ether until the two layers disappear, and allow to stand for 2 hours at 0¡ to precipitate the title product. There are many ways to reduce 2-carbomethoxytropinone to methylecgonine. I chose to design a Raney Nickle reduction because it is cheap and not as suspicious as LAH and it is much easier than zinc or sodium amalgams.