In our nucleophilic trifluoromethoxylation protocol, a secondary alkyl bromide was swiftly converted into the corresponding product in good yields (Scheme 2, entry 53). The reaction proved to be versatile by delivering products in good to excellent yields for allylic and benzylic substrates bearing multiple functionalities and heterocyclic scaffolds. These were also represented by API intermediate derivatives, such as Celecoxib, Pitavastin, Umifenovir, and a Lonazolac analog (Scheme 2, entries 54-59). Moreover, the trifluoromethoxy anion was also reacted in a SNAr manifold (Scheme 2, entry 60) and used to modify glycosyl substrates (Scheme 2, entries 61 and 62). Furthermore, our methodology can be extended to incorporate longer polyfluoroethoxy chains. By flowing fluoroalkyl anhydrides as anion precursors through the CsF-packed bed, these substrates can initially undergo acyl fluoride formation, followed by alkoxy anion formation upon a second fluoride addition. We employed this strategy to obtain tetra-and pentafluoroethoxy-derived glycosyl products (Scheme 2, entries 63 and 64). Scheme 2. On demand generation of SCF3 and OCF3 anions and its reaction with electrophiles. All yields are those of isolated compounds unless otherwise noted. Standard conditions for anion generation: thiophosgene or diphosgene (0.1 M in MeCN with 1 equiv of 18-crown-6) was passed through a 3.8 mL cartridge filled with a 7:3 w/w mixture of CsF and glass beads. Standard conditions for the fed batch substitution: electrophile (0.2 mmol) is added to the solution of the anion (from 2.5 to 7 equiv) and stirred at room temperature. For the fluoralkoxylation reactions 1 equiv of AgOTf was used. For detailed reaction conditions of each substrate see the S.I. a From the bromide. b From the mesylate. c See S.I. for telescoped-flow conditions. d From fluoride. e From the acyl chloride using 3 equiv. of TMSCl. f NMR yield reported due to the volatility of the product. g From the [N2•BF4]. h Difluoroacetic anhydride was used as anion precursor. i Trifluoroacetic anhydride was used as anion precursor.