80945-05-7Relevant articles and documents
Copper-Catalyzed C(sp3)?H Amidation: Sterically Driven Primary and Secondary C?H Site-Selectivity
Bakhoda, Abolghasem (Gus),Jiang, Quan,Badiei, Yosra M.,Bertke, Jeffery A.,Cundari, Thomas R.,Warren, Timothy H.
, p. 3421 - 3425 (2019/02/14)
Undirected C(sp3)?H functionalization reactions often follow site-selectivity patterns that mirror the corresponding C?H bond dissociation energies (BDEs). This often results in the functionalization of weaker tertiary C?H bonds in the presence of stronger secondary and primary bonds. An important, contemporary challenge is the development of catalyst systems capable of selectively functionalizing stronger primary and secondary C?H bonds over tertiary and benzylic C?H sites. Herein, we report a Cu catalyst that exhibits a high degree of primary and secondary over tertiary C?H bond selectivity in the amidation of linear and cyclic hydrocarbons with aroyl azides ArC(O)N3. Mechanistic and DFT studies indicate that C?H amidation involves H-atom abstraction from R-H substrates by nitrene intermediates [Cu](κ2-N,O-NC(O)Ar) to provide carbon-based radicals R. and copper(II)amide intermediates [CuII]-NHC(O)Ar that subsequently capture radicals R. to form products R-NHC(O)Ar. These studies reveal important catalyst features required to achieve primary and secondary C?H amidation selectivity in the absence of directing groups.
SENSITIZED PHOTOLYSIS OF BENZOYL AZIDE. A NITRENE SINGLET-TRIPLET EQUILIBRIUM
Inagaki, Masao,Shingaki, Tadao,Nagai, Toshikazu
, p. 9 - 12 (2007/10/02)
The acetophenone-sensitized photolyses of benzoyl azide in cis- and trans-1,4-dimethylcyclohexanes gave the N-substituted benzamides stereospecifically.The photolyses in 2,3-dimethylbutane showed the same insertion regioselectivity ratio toward the C-H bonds as that of singlet benzoylnitrene in the direct photolysis.These facts indicate the existence of the singlet nitrene despite the triplet photosensitization and provide a chemical evidence for the establishment of a singlet-triplet equilibrium for benzoylnitrene.
INSERTION OF BENZOYLNITRENE TOWARD HYDROCARBON C-H BONDS
Inagaki, Masao,Shingaki, Tadao,Nagai, Toshikazu
, p. 1419 - 1422 (2007/10/02)
Benzoylnitrene, generated photochemically from benzoyl azide, was inserted stereospecifically into the tertiary C-H bonds of cis- and trans-1,4-dimethylcyclohexanes.The insertion regioselectivities toward the C-H bonds were determided by use of 2-methylbutane and 2,3-dimethylbutane.The insertion proceeds involving the singlet nitrene, but not the triplet, and the photoCurtius rearrangement takes place independently of the nitrene reaction.
