## 5 Oxidation of Functionalised Hydrocarbons
### Haloalcohols as Substrates  
Haloalcohols or halohydrins were also intermediates in the oxhylogenation reactions discussed above. Therefore, it is important to note the close relationship between the two sections and that protocols discussed in this section could also help to advance the oxhylogenation strategies.  
[PERSON] and [PERSON] independently developed a micellar catalytic oxidation of alcohols [173, 174]. Both authors reported the successful conversion of 2-bromo-1-phenylethanol into its corresponding ketone (Table 6). [PERSON] and co-workers enhanced the substrate's water solubility upon addition of CTAB, a commercially available cationic surfactant, to the reaction medium. Similarly, [PERSON] and co-workers ensured the sufficient solubility of the substrate by adding GMPGS-2000, a non-ionic surfactant. Both procedures exploited the concept of micellar catalysis, which truly distinguished them from the state-of-the-art. However, one major flaw of these micellar catalytic systems concerns the often tedious work-up, attributed to the difficult separation of the organic and aqueous phase [175].  
A copper-catalysed oxidation of secondary alcohols was designed by [PERSON] and co-workers [176]. 2-Bromo-1-phenylethanolamine was isolated in 95% yield upon addition of Cu(OTf) (0.05 equiv.), TEMPO (0.05 equiv.), (5)-5-(pyrrolidin-2-yl)-1\(H\)-tetrarole (0.05 equiv.) and KOrBu (1 equiv.) to the corresponding alcohol in dimethylformamide (DMF) at room temperature. However, no reaction/substrate scope was disclosed. Another limited protocol was developed by [PERSON] and co-workers using AlMe\({}_{3}\)-catalysed Oppenauer oxidation (Scheme 70) [177]. The scope again consisted of one \(\alpha\)-haloketone, i.e., 2-bromo-1-phenylethanolone, making it difficult to assess the method's efficiency.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Reaction Conditions** & **Scope (Yield)** & **Refs.** \\ \hline
2-iodosylbenzoic acid (0.01 equiv.), Oxone® (0.525 equiv.), CTAB (3 wt\%), H\({}_{2}\)O, r.t., 2 h & 2-bromo-1-phenylethanolamine (95\%) & [173] \\ IBX (1.2 equiv.), GMPGS-2000 (2 wt\%), H\({}_{2}\)O, r.t., 24 h & 2-bromo-1-phenylethanolamine (64\%) & [174] \\ \hline \hline \end{tabular}
\end{table}
Table 6: Micellar catalytic oxidation of 2-bromo-1-phenylethanol.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Method** & **Reaction Conditions** & **Scope (Yield)** & **Aromatic Substituents** \\ \hline
**1** & Fe(OTf)\({}_{3}\) (1.15 mol\%), L4 (1.15 mol\%), DCE, & 2 \(\alpha\)-Bromoketones (91–92\%) & H, Cl \\
2 & Fe(OTf)\({}_{3}\) (1.15 mol\%), L1 (1.15 mol\%), O\({}_{2}\) (1 atm), & 4 \(\alpha\)-Bromoketones (65–99\%) & \\
2 & DCE/DBE 75 \({}^{\circ}\)C, 8 h & 1 \(\alpha\)-Iodoketones (70\%) & H, Me, OMe, F, Cl, Br \\ \hline \hline \end{tabular}
\end{table}
Table 5: Fe\({}^{\text{III}}\)-catalysed oxidation of haloalkenes.  
He and co-workers described the bis(methoxypropyl)ether (bMPE)-promoted oxidation of benzylic alcohols [178]. The procedure yielded one \(\alpha\)-bromo- and one \(\alpha\)-chloroketone in good yields (Scheme 71). Although again the scope was limited, the main advantage of this protocol is its solvent-free conditions.  
In 2014, [PERSON] published a _T. versicolor_ Lacasse and TEMPO system, which converted haloalcohols into their corresponding ketones [179]. _T. versicolor_ Lacasse is an extracellular enzyme excreted by white and brown fungi. A broad scope of \(\alpha\),\(\alpha\)-dihalogenated aryl ketones were obtained in good to excellent yields. The chemoenzymatic procedure also yielded one \(\alpha\)-halocarbonyl compound, i.e., 2-chloro-1-phenylethanolamine, at a yield of 62%. Despite the mild reaction conditions, the long reaction times (24 h) and the moderate yield still limited the method's applicability.