- Aerobic C(sp2)-H Hydroxylations of 2-Aryloxazolines: Fast Access to Excited-State Intramolecular Proton Transfer (ESIPT)-Based Luminophores
-
The direct hydroxylation of 2-aryloxazolines via a deprotonative magnesiation using TMPMgCl·LiCl and subsequent oxidation with molecular oxygen or air as a green oxidant is reported. This method proceeds under mild conditions at room temperature with high regioselectivity and chemoselectivity. The obtained phenols exhibit tunable luminescence properties, induced by excited-state intramolecular proton transfer. This method opens a new opportunity for the sustainable synthesis of luminescent organic molecules.
- G?bel, Dominik,Clamor, Nils,Lork, Enno,Nachtsheim, Boris J.
-
p. 5373 - 5377
(2019/06/07)
-
- Directed ortho-Metalation of O-Aryl N,N-Dialkylcarbamates: Methodology, Anionic ortho-Fries Rearrangement, and Lateral Metalation
-
The directed ortho-lithiation reactions of O-aryl N,N-dialkylcarbamates as well as O-1-naphthyl and O-2-naphthyl N,N-dialkylcarbamates with sec-butyllithium/tetramethylethylenediamine (sBuLi/TMEDA) followed by quenching with various electrophiles afford a range of polysubstituted aromatic compounds. If the solutions of the ortho-lithiated carbamates are warmed to room temperature without the addition of external electrophiles, salicylamide and 1- and 2-hydroxynaphthamide derivatives are formed through anionic ortho-Fries rearrangements. The relative stabilities and reactivities of different O-aryl N,N-dialkylcarbamates were investigated. The lateral metalation of 2-tolyl carbamates with lithium diisopropylamide (LDA) provides a route to benzo[b]furan-2(3H)-ones. Previously reported results are used in a comparison of seven O-based directed metalation groups in reactions with several electrophiles. The described methodology is useful for the preparation of 1,2,3-substituted aromatic compounds.
- Miah, M. A. Jalil,Sibi, Mukund P.,Chattopadhyay,Familoni, Oluwole B.,Snieckus, Victor
-
p. 440 - 446
(2017/12/15)
-
- Ortho-and para-selective ruthenium-catalyzed C(sp2)-H oxygenations of phenol derivatives
-
Versatile ruthenium catalysts allowed for efficient direct oxygenations of aryl carbamates under remarkably mild reaction conditions. In addition to chelation-assisted C-H activation, the optimized ruthenium catalyst proved amenable to para-selective hydroxylations of anisoles without Lewis basic directing groups.
- Liu, Weiping,Ackermann, Lutz
-
supporting information
p. 3484 - 3486
(2013/07/26)
-
- Arylsilane oxidation - New routes to hydroxylated aromatics
-
An efficient route to hydroxylated aromatics has been developed, via the oxidation of aryl organosilanes under functional group-tolerant and relatively mild conditions, using sub-stoichiometric amounts of fluoride promoters.
- Bracegirdle, Sonia,Anderson, Edward A.
-
supporting information; experimental part
p. 3454 - 3456
(2010/07/16)
-
- Hydroxylation of carbanions with lithium teri-butyl peroxide acting as an oxenoid
-
The lithium salt of terf-butyl hydroperoxide can convert alkyl, vinyl, aryl carbanions, acetylides and various enolates into the corresponding hydroxylated derivatives in good yields and under mild conditions. Eisevier.
- Julia, Marc
-
-