Anthracene, acetamidation

Anodic oxidation of anthracene in MeCN containing (CF3C0)20 (to remove water and suppress hydroxylation) leads to the formation of the acetamidation product in 85% yield [159]. Results obtained by cyclic voltammetry supported the mechanism shown in Eq. (47). 

Anodic oxidation of n-alkanes in acetonitrile results in mixtures of A -s-alkylacetamides but skeletal rearrangement of the intermediate i-carbenium ions is not observed. Aromatic compounds can undergo direct acetamidation in the ring. Thus, acetophenone, which normally undergoes electrophilic aromatic substitution at the meta position, affords the o- and p-acetamides (Scheme 44). Anthracene is cleanly converted into the acetamide (84) when the reaction is performed in the presence of TFAA as water scavenger (equation 41). ... 

The arynes 4,5-dehydro- and 4,5,15,16-bis(dehydro)octafluoro[2.2]paracycloph anes, 162 and 163 (Figure 12.2), generated from the corresponding aryl iodide [87] or acetamide [88], have been captured in Diels-Alder reachons by Dolbier and coworkers. Aromatics, such as benzene, naphthalene, anthracene and furan... 

The two examples portrayed below, each occurring via different mechanistic pathways, give one a sense of the breadth of the chemistry. In the first (Eq. 2), different nucleophiles, viz., azide and methanol, add across a double bond [5]. The more nucleophilic of the pair adds to the less substituted carbon to afford a heteroatom-stabilized cation that is then intercepted by the second nucleophile, ultimately delivering the product (Eq. 3). The second example portrays the replacement of a C-H bond on anthracene with acetonitrile to afford the acetamide adduct after hydrolysis of the nitrilium ion intermediate (Eq. 4) [6]. 

Hammerich O, Parker VD (1974) Reaction of the anthracene cation radical with acetonitrile. A novel anodic acetamidation. J Chem Soc Chem Commun 7 275-276... 

---