= Solution
\b[G is the diaryl <ether> $\mathrm{(2{-}NO_2C_6H_4){-}O{-}(2{-}CH_2C(=O)N_{morph}C_6H_4)}$.] Here $N_{morph}$ denotes the <nitrogen> of the intact morpholine ring; the phenoxy <oxygen> and phenylacetamide chain are ortho on their original ring. <potassium> <carbonate> first generates <phenoxide> from F. Its <oxygen> attacks the <fluorine>-bearing <carbon> of 1-fluoro-2-<nitrobenzene>, forming a <Meisenheimer complex>. Delocalization of its negative charge into the ortho <nitro group> stabilizes this addition intermediate. Fluoride elimination restores <aromaticity> and completes <nucleophilic aromatic substitution>.
This first step forms an O–aryl bond, rather than immediately arylating the less acidic alpha <carbon>. The neutral <product (chemistry)> has formula $\mathrm{C_{18}H_{18}N_2O_5}$, obtained from the two <substrate (chemistry)>s by net loss of HF. The connectivity is shown beside B in the independently drawn diagram above. The <amide>-<substrate (chemistry)> O-to-C migration strategy has direct primary precedent.<Developing the Scope of O→C Aryl Migrations: Exploring Amide Substrates as Potential Precursors for Asymmetric Reactions by Dana Ameen and Timothy J. Snape>[2014, pp. 1925–1934, amide substrates and five-membered rearrangement pathways]{ref}
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