Phenylacetone is derived from acetone and contains a phenyl group as a substituent, which is why it is also commonly named phenyl-2-acetone or P2P. Most derivatives contain substituents in their phenyl groups, which give them different properties. Phenylacetone is present in food additives as a flavoring agent, including flavorings and condiments; They are often involved in the synthesis of many chemical intermediates. Phenylacetone is very important in the pharmaceutical industry for the production of central nervous system (CNS) active compounds and anticoagulants. In the pesticide industry, phenylacetone is present to a lesser extent in the synthesis of some pesticides.

Phenylacetone is an organic compound with the formula C6H5CH2C (=O) CH3. It is a colorless oil that is soluble in organic solvents but insoluble in water. This substance is used to make amphetamine-type substances such as methamphetamine, commonly known as P2P. As such, it is a Schedule II controlled substance in the United States (and most of the world) and is not freely available.

Walt and Jesse produce P2P in the basement of the latter's house by heating phenyl acetic acid in a 70 mm tube furnace at 425°C with ice acetic acid or acetic anhydride for several hours in the presence of a thorium oxide catalyst. In the desert, Walter and Jesse produce enough P2P to cook 42 pounds of meth.

The reduction amination of P2P produces amphetamine.

The reaction of P2P with bleach will produce chloroform and phenylacetic acid.

If sodium hydroxide and iodine are used instead of bleach, yellow iodoform is formed. This reaction can be used as a qualitative test for methyl ketone.

In the show, the crude P2P Walt gets directly from the tube furnace is milky white, which means it is impure and usually contaminated with water. However, according to all descriptions in the literature and other sources, the crude P2P distillate obtained from this route is always yellow or orange due to various trace amounts of other aromatic compounds formed as by-products (similar to how the crude benzene distillate obtained from decarboxylation of sodium benzoate is orange). Pure P2P must be distilled again under reduced pressure to prevent excessive distillation of contaminants, and then dried with anh. CaSO4 or MgSO4.

Although not shown, because the tube furnace blocks the view, Walt may pass the crude distillate through activated carbon to remove by-products, and then azeotropic distillation of wet emulsion P2P with benzene to dry it.