The Proper Preparation of Aluminum Amalgam

by Eleusis

This is for all of you Dr. Shulgin fans out there that might be a little miffed at poor yields when attempting mild reductive aminations (not the fruity little Disney characters, kids). The trick here is *cleaning* the damned foil before you use it. Follow closely, be careful with the mercuric solutions, they can be absorbed transdermally (in other words, use gloves, dumbass).

Preparation of Aluminum Amalgam

Aluminum Amalgam is a useful mild reducing agent which requires careful preparation in order to be effective. The following is adapted from Vogel's Practical Organic Chemistry.

Prepare 10% Sodium Hydroxide solution by dissolving 20g NaOH in 180mL of distilled water.

Prepare a ~2% Mercuric (II) Chloride solution by dissolving 1g of HgCl2 in 50mL of distilled water.

Cut 40g of aluminum foil into small squares approximately .5cm a side.

Place the aluminum into a large beaker or other suitable glass container and cover with the sodium hydroxide solution. Heat gently in a well ventilated area until hydrogen gas evolves vigorously for about 3 minutes. Strain the foil through a plastic colander and wash first with distilled water, then with denatured alcohol. Pat dry then add to a beaker with the 2% HgCl2 solution. Allow to amalgamate for 2 minutes then pour off the supernatant. It is unethical to pour mercury compounds down the drain, but you'll probably do it anyway ;-). Now wash the foil in the colander as before, with distilled water, ethanol, and then a little bit of ether. Submerge the aluminum amalgam in ether to store until use.

- - Aluminum Amalgam Doc - 09/01/95 -