Synthesis and reactivity of aliphatic sulfur pentafluorides from substituted (pentafluorosulfanyl)benzenes

• Norbert Vida,
• Jiří Václavík and
• Petr Beier

Beilstein J. Org. Chem. 2016, 12, 110–116, doi:10.3762/bjoc.12.12

• transformations: electrophilic aromatic hydroxylation to the intermediate 6, oxidation to ortho-benzoquinone 7, Baeyer–Villiger (BV) oxidation, hydrolysis to muconic acid derivative 8, and finally intramolecular conjugate addition affording 3. Under certain conditions, small amounts of intermediates 6 and 8 were

• maleic acid derivative 4 in the product mixture. Control experiments in which 8 or 3 were reacted with H2O2/H2SO4 did not provide 4. This suggests that 4 may be formed by a second hydroxylation of 6 to 9. The second electrophilic aromatic hydroxylation is a favorable process because 6 is a more activated

Complete σ* intramolecular aromatic hydroxylation mechanism through O₂ activation by a Schiff base macrocyclic dicopper(I) complex

• Albert Poater and
• Miquel Solà

Beilstein J. Org. Chem. 2013, 9, 585–593, doi:10.3762/bjoc.9.63

• Grahit 101, E-17003 Girona, Spain 10.3762/bjoc.9.63 Abstract In this work we analyze the whole molecular mechanism for intramolecular aromatic hydroxylation through O2 activation by a Schiff hexaazamacrocyclic dicopper(I) complex, [CuI2(bsH2m)]2+. Assisted by DFT calculations, we unravel the reaction

• pathway for the overall intramolecular aromatic hydroxylation, i.e., from the initial O2 reaction with the dicopper(I) species to first form a CuICuII-superoxo species, the subsequent reaction with the second CuI center to form a μ-η2:η2-peroxo-CuII2 intermediate, the concerted peroxide O–O bond cleavage

• and C–O bond formation, followed finally by a proton transfer to an alpha aromatic carbon that immediately yields the product [CuII2(bsH2m-O)(μ-OH)]2+. Keywords: aromatic hydroxylation; C–H bond activation; C–H functionalization; copper; DFT calculations; mechanism; Schiff base; Introduction Bearing

Regio- and stereoselective oxidation of unactivated C–H bonds with Rhodococcus rhodochrous

• Elaine O’Reilly,
• Suzanne J. Aitken,
• Gideon Grogan,
• Paul P. Kelly,
• Nicholas J. Turner and
• Sabine L. Flitsch

Beilstein J. Org. Chem. 2012, 8, 496–500, doi:10.3762/bjoc.8.56

• -arylpiperidines can direct hydroxylation away from the substituted position and improve the product yield [18]. Although we did not observe any aromatic hydroxylation of 3a during our studies, we observed a significant improvement in regioselectivity with the THPs 3b–d, in which a substituent was present on the