Allylic with ortho-substituted phenols

Tab. 10.7 summarizes the results of the application of rhodium-catalyzed allylic etherification to a series of ortho-substituted phenols. The etherification tolerates alkyls, including branched alkanes (entries 1 and 2), aryl substituents (entry 3), heteroatoms (entries 4 and 5), and halogens (entry 6). These results prompted the examination of ortho-disubstituted phenols, which were expected to be more challenging substrates for this type of reaction. Remarkably, the ortho-disubstituted phenols furnished the secondary aryl allyl ethers with similar selectivity (entries 7-12). The ability to employ halogen-bearing ortho-disubstituted phenols should facilitate substitutions that would have proven extremely challenging with conventional cross-coupling protocols. 

Phenolic compounds substitutable at the para-position are 4-nonyljiienol, 4-(l,l-dimethyiethyl) 4ienol, 4-(l-adamantyl)phenol, and4-arylazo-3-aminophenol. These phenolic compounds have the two ortho positions free for reaction with methanal. Another substituted monomer is 2-allyl-3(5)-pentadecylphenol. The 2-allyl-3 (5)-pentadecylphenol can react with methanal either at the para position or ortho position. In case of the two nucleus phenoUc compound 4,4 -(l-... 

Focusing on benzene-like arenes, Shu-Li You described an efficient intramolecular Ir-catalyzed nucleophilic allylic substitution of phenols, addressing meto-substituted hydroxyarene with allylic carbonate side chains 31 as acyclic precursors [20]. A range of tetrahydroisoquinolines 33 was isolated in good yields (up to 90%) and ee up to 96% in the presence of chiral phosphoramidite ligand (5,5,5 )-32 (4mol%) and [IrCKCOD)] as the metal source (Scheme 5.10). The use of DMAP as an additive (200 mol%) in THF (rt to 50°C) allowed the regiochemical ortho aromatic C—H replacement (33 vs. 33 ) prevalently. 

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