Monday, October 10, 2016

The Illicit Preparation of Morphine and Heroin from Pharmaceutical Products Containing Codeine:

1. Extraction of codeine
Several packets of tablets, sufficient to yield about 2 g of codeine, are crushed and mixed with water. The mixture is filtered using a filter pump, Buchner funnel and side-arm flask, to remove tablet binding agents, diluents and other excipients. The aqueous filtrate is poured into a separating funnel and sodium hydroxide solution added to make the solution strongly alkaline. This is then extracted with chloroform (about 50 ml). The chloroform layer is drained off and evaporated to dryness using gentle heating (often on a domestic stove). The aqueous layer containing aspirin and paracetamol is discarded. The codeine base is recovered as a white crystalline solid for use in Step 3.
2. Preparation of pyridine hydrochloride
In a beaker pyridine (20 ml) and concentrated hydrochloric acid (25 ml) are strongly heated (to about 190°C) to drive off water. The product is cooled rapidly to form a waxy white solid which is stored in a sealed container in a freezer to minimise exposure to moisture and avoid decomposition.
3. Reaction of codeine and pyridine hydrochloride
The reaction is carried out using a boiling tube which is flame-dried before use. Pyridine hydrochloride (3.5 g) as prepared in Step 2 is then heated in the tube until it melts and any residual moisture is driven off. Any resulting condensation on the inside walls of the tube is wiped off. Codeine base (1.5 g) is added to the tube which is then stoppered with a rubber bung covered with filter paper and heated until the mixture starts to fume. Heating is continued until a reddish-orange colour develops in the reaction melt, which becomes noticeably more viscous (6-12 min). The contents of the boiling tube are then poured into a 500 ml separating funnel and the volume made up to 100 ml with water. Sodium hydroxide solution (10%) is added until the contents of the separating funnel are strongly basic. As the sodium hydroxide is added the contents turn milky-brown before becoming clear brown again. Chloroform (20 ml) is added. After extraction the greyish-brown chloroform layer is either discarded or put aside for later recovery of the codeine contained in it. The aqueous layer is poured into a 400 ml beaker and the pH is carefully adjusted to pH 9 using hydrochloric acid and narrow-range indicator paper. The solution is rapidly filtered under suction, using a Buchner funnel and 2 filter papers, to remove a fine, dark brown residue containing unwanted by-products. The filtered solution is then poured into a clean beaker and precipitation is induced by vigorously rubbing the side of the beaker with a 'seeding stick' as the pH is carefully lowered to 8.5 with additional hydrochloric acid. (In homebake laboratories a split wooden clothes peg is often used as the 'seeding stick'.) The product is allowed to settle for at least 5 min before being filtered off under vacuum. The morphine product is recovered as a powder, ranging in colour from beige to dark brown.
4. Conversion of morphine to heroin
Morphine powder as prepared in Step 3 is placed in a spoon. A small amount of acetic anhydride is added and the mixture ignited. Addition of acetic anhydride may be repeated. A brown or black tar-like residue remains.

https://www.erowid.org/archive/rhodium/chemistry/codeine.homebake.labs.html

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