## 7 Miscellaneous Routes  
### \(\alpha\)-Functionalised Ketones as Substrates  
In 2018, [PERSON] published the selective monodehalogenation of \(\alpha\),\(\alpha\)-dihaloketones (201). 2-Iodo-1-phenylethanone was isolated in 64% yield upon stirring the \(\alpha\),\(\alpha\)-diiodo-product for 10 h in a CH\({}_{3}\)CN/H\({}_{2}\)O mixture. The procedure yielded an inseparable mixture of the \(\alpha\)-haloketone and \(\alpha\),\(\alpha\)-dihaloketone for 2-bromo-1-phenylethanone. Alternatively, [PERSON] et al. established an IL-mediated selective debromination method in which 1-methyl-3-pentylimidazolium tetra-fluoroborate ([pmlm]BF\({}_{4}\)) acted as both catalyst and reaction medium (202). Two aromatic \(\alpha\)-bromoketones (R = H, Me) and one \(\alpha\)-chloroketone (R = Me) were generated in good yields (Scheme 78). This route exhibited short reaction times, excellent efficacy and selectivity, and the use of a recyclable and readily available catalyst. In the last decade, [PERSON] and co-workers dedicated considerable effort towards the development of an effective S\({}_{N}\)2 substitution protocol yielding \(\alpha\)-functionalised ketones from their corresponding \(\alpha\)-bromoketones (203; 204; 205; 206). Their most recent work involved an imidazolium poly(ionic liquid)-based substitution (Scheme 79). Four aromatic \(\alpha\)-iodoketones were obtained in excellent yields (87-91%) upon the addition of the IL and NaI to the substrate in H\({}_{2}\)O at 60 \({}^{\circ}\)C. The authors claimed that the IL can be recycled and reused in up to five consecutive runs without significant loss in activity. This route has some promising features, i.e., catalyst recycling, aqueous solvent and mild reaction conditions; however, it still suffers from the need to synthesise the \(\alpha\)-bromoketone substrate. An alternative substitution procedure, developed by [PERSON] and co-workers, generated 14 \(\alpha\)-chloroketones in quantitative yields from \(\alpha\)-bromoketones (Scheme 80) (207). This route tolerated the presence of electron-donating and -withdrawing aromatic substituents. Additionally, sterically hindered substrates were tolerated. This procedure afforded quantitative yields, thus avoiding chromatographic purification of the products. [PERSON] and co-workers designed a synthetic protocol converting \(\alpha\)-diazoketones in \(\alpha\)-halo-ketones (Scheme 81) [208]. The protocol yielded ten \(\alpha\)-chloroaryl ketones in 56-82% when stirring a mixture of FeCl\({}_{3}\) (0.5 equiv. ), silica gel (100 mg) and the diazo compound in DCM for 10 min. Furthermore, seven \(\alpha\)-bromoaryl ketones were obtained in moderate to excellent yields (55-95%) by changing the Lewis acid to FeBr\({}_{3}\). This route's versatility was demonstrated through its tolerance towards electron-donating (e.g., Me, OMe) and -withdrawing (e.g., I, Cl, NO\({}_{2}\)) aromatic substituents, as well as sterically hindered substrates. [PERSON] and [PERSON] developed a continuous process for the synthesis of \(\alpha\)-chloroketones from their acetyl chloride derivatives (Scheme 82) [209; 210]. The protocol involved mixing a \(N\)-methyl-\(N\)-nitroso-\(p\)-toluenesulfonamide (diazid) solution in DMF and a KOH solution in MeOH/H\({}_{2}\)O with the starting material to afford the \(\alpha\)-diazoketone intermediate. Subsequent addition of HCl allowed the isolation of four aromatic \(\alpha\)-chloroketones in excellent yields (88-90%). The on-demand generation and direct consumption of diazomethane or its precursor certainly eliminate human exposure to the reagent, thus reducing the risk of explosive decomposition. [PERSON] and co-workers aimed to establish a sustainable procedure for the Appel halogenation, which converts alcohols in alkyl halides [211]. Although a broad scope of halides was obtained, the procedure only yielded two aryl \(\alpha\)-haloketones (Scheme 83).