4237-37-0Relevant articles and documents
Catalyst-Controlled Regioselective Chlorination of Phenols and Anilines through a Lewis Basic Selenoether Catalyst
Dinh, Andrew N.,Maddox, Sean M.,Vaidya, Sagar D.,Saputra, Mirza A.,Nalbandian, Christopher J.,Gustafson, Jeffrey L.
, p. 13895 - 13905 (2020/11/03)
We report a highly efficient ortho-selective electrophilic chlorination of phenols utilizing a Lewis basic selenoether catalyst. The selenoether catalyst resulted in comparable selectivities to our previously reported bis-thiourea ortho-selective catalyst, with a catalyst loading as low as 1%. The new catalytic system also allowed us to extend this chemistry to obtain excellent ortho-selectivities for unprotected anilines. The selectivities of this reaction are up to >20:1 ortho/para, while the innate selectivities for phenols and anilines are approximately 1:4 ortho/para. A series of preliminary studies revealed that the substrates require a hydrogen-bonding moiety for selectivity.
Toward a Catalytic Atroposelective Synthesis of Diaryl Ethers Through C(sp 2)-H Alkylation with Nitroalkanes
Dinh, Andrew N.,Noorbehesht, Ryan R.,Toenjes, Sean T.,Jackson, Amy C.,Saputra, Mirza A.,Maddox, Sean M.,Gustafson, Jeffrey L.
supporting information, p. 2155 - 2160 (2018/09/29)
We report studies toward a small-molecule-catalytic approach to access atropisomeric diaryl ethers that proceeds through a C(sp 2)-H alkylation using nitroalkanes as the alkyl source. A quaternary ammonium salt derived from quinine, containing
2,2,6,6-Tetramethylpiperidine-catalyzed, ortho-selective chlorination of phenols by sulfuryl chloride
Saper, Noam I.,Snider, Barry B.
, p. 809 - 813 (2014/04/03)
2,2,6,6-Tetramethylpiperidine (TMP)-catalyzed (1- 10%) chlorinations of phenols by SO2Cl2 in aromatic solvents are more ortho selective than with primary and less hindered secondary amine catalysts. Ortho-selective chlorination is successful even with electron deficient phenols such as 2-hydroxybenzaldehyde and 2'- hydroxyacetophenone. Notably, ortho selectivity increases with the reaction temperature. On the other hand, tetraalkylammonium chloride-catalyzed chlorinations are moderately para selective.