Assessing the accuracy and methodology of the chemistry in Breaking Bad
Edward Ellam
Breaking Bad is one of the most critically acclaimed television shows over the past decade. The show focuses on Walter White, a Caltech graduate chemistry teacher who decides to pursue a career of crime primarily through the synthesis (or ‘ cooking ’ ) of methamphetamine. Chemistry is the foundation of the show, not only in the synthesis of the methamphetamine but also in various situations throughout. Therefore, one should assume that the chemistry should be accurate. Over this essay the accuracy and methodology of the chemistry during the show will be discussed, concluding that it is not fully accurate.
N-metamphetamine synthesis
There are two primary ways of synthesizing methamphetamine used in the show. The first way initially used involves PI 3 made in situ reducing ( S)- pseudoephedrine (found in cough syrup) to methamphetamine as shown in figure 1. The reaction in the reduction stage goes as follows
2𝑃+3𝐼 2 +6𝐻 2 𝑂 →2𝑃𝐼 3 +6𝐻 2 𝑂 → 6𝐻𝐼 + 2𝐻 3 𝑃𝑂 3 .
The HI is a strong reducing agent because, due to the large ionic radius of I - ions, it is easy for it to lose electrons. The HI reduces the (1 s,2s) -pseudoephedrine by removing the OH group to produce ( S )-N-methamphetamine. This method produces an optically active isomer of N-methamphetamine. The second method ( ‘ blue sky ’ ) used in the show is based on phenylacetic acid. In the first step the phenylacetic acid is reduced by acetic acid with a thorium dioxide catalyst. This step is dangerous due
to the radioactive thorium dioxide, and explains why the characteristic yellow suits are used during the show. The second step involves the further reduction of phenylacetone by aluminium amalgam (an alloy of magnesium containing mercury) along with the addition of a methylamine group. Aluminium is an effective reducing agent due to its tendency to lose 3 electrons as follows 𝐴𝑙 →𝐴𝑙 3+ + 3𝑒 − . By amalgamating with mercury, the unreactive Al 2 O 3 layer is removed, allowing the aluminium to react. Throughout the show the addition of aluminium amalgam is often forgotten: without it the reaction would not occur. The blue colour from the show is also inaccurate, as unless there are impurities, the N-methamphetamine should be colourless. Furthermore, the second reaction produces a racemic product of (S )/( R )-N-methamphetamine. As the S-isomer is significantly more potent than its R counterpart, the racemic mixture of N-methamphetamine produced from the second method should be less potent which is opposite to how it is viewed in the show. Figure showing the ways of synthesizing (S)-N- methamphetamine. From ‘The chemistry of Breaking Bad ‘
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