732-26-3Relevant articles and documents
Selective Preparations; 27. A Convenient Preparation of 1-Hydroxydibenzofuran from 2-Bromo-4,6-di-t-butylphenol
Tashiro, Masashi,Yoshiya, Haruo,Fukata, Gouki
, p. 495 - 496 (1980)
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Westerberg, D. Eric,Sutherland, Bruce R.,Huffman, John C.,Caulton, Kenneth G.
, p. 1642 - 1643 (1988)
ACTIVITY OF SECONDARY AROMATIC AMINES AS CATALYSTS IN THE REACTION OF STERICALLY HINDERED AROXYL RADICALS WITH HYDROPEROXIDES
Varlamov, V. T.
, p. 482 - 490 (1989)
Secondary aromatic amines AmH catalyze the reaction of the 2,4,6-tri-t-butylphenoxyl radical ArO* with cumyl hydroperoxide ROOH.This effect is closely connected with the antioxidant action of the mixtures of sterically hindered phenols and AmH which have a synergistic effect and which are used in practice.The present work is directed to a study of the dependence of the catalytic activity of AmH on the temperature and on the substituents on the aromatic rings.
Visible light enables catalytic formation of weak chemical bonds with molecular hydrogen
Park, Yoonsu,Kim, Sangmin,Tian, Lei,Zhong, Hongyu,Scholes, Gregory D.,Chirik, Paul J.
, p. 969 - 976 (2021/07/25)
The synthesis of weak chemical bonds at or near thermodynamic potential is a fundamental challenge in chemistry, with applications ranging from catalysis to biology to energy science. Proton-coupled electron transfer using molecular hydrogen is an attractive strategy for synthesizing weak element–hydrogen bonds, but the intrinsic thermodynamics presents a challenge for reactivity. Here we describe the direct photocatalytic synthesis of extremely weak element–hydrogen bonds of metal amido and metal imido complexes, as well as organic compounds with bond dissociation free energies as low as 31 kcal mol?1. Key to this approach is the bifunctional behaviour of the chromophoric iridium hydride photocatalyst. Activation of molecular hydrogen occurs in the ground state and the resulting iridium hydride harvests visible light to enable spontaneous formation of weak chemical bonds near thermodynamic potential with no by-products. Photophysical and mechanistic studies corroborate radical-based reaction pathways and highlight the uniqueness of this photodriven approach in promoting new catalytic chemistry. [Figure not available: see fulltext.].
Multiple N-H and C-H Hydrogen Atom Abstractions through Coordination-Induced Bond Weakening at Fe-Amine Complexes
Wang, Zongheng,Johnson, Samantha I.,Wu, Guang,Ménard, Gabriel
, p. 8242 - 8251 (2021/06/25)
We report the use of the reported Fe-phthalocyanine complex, PcFe (1; Pc = 1,4,8,11,15,18,22,25-octaethoxy-phthalocyanine), to generate PcFe-amine complexes 1-(NH3)2, 1-(MeNH2)2, and 1-(Me2NH)2. Treatment of 1 or 1-(NH3)2 to an excess of the stable aryloxide radical, 2,4,6-tritert-butylphenoxyl radical (tBuArO?), under NH3 resulted in catalytic H atom abstraction (HAA) and C-N coupling to generate the product 4-amino-2,4,6-tritert-butylcyclohexa-2,5-dien-1-one (2) and tBuArOH. Exposing 1-(NH3)2 to an excess of the trityl (CPh3) variant, 2,6-di-tert-butyl-4-tritylphenoxyl radical (TrArO?), under NH3 did not lead to catalytic ammonia oxidation as previously reported in a related Ru-porphyrin complex. However, pronounced coordination-induced bond weakening of both α N-H and β C-H in the alkylamine congeners, 1-(MeNH2)2 and 1-(Me2NH)2, led to multiple HAA events yielding the unsaturated cyanide complex, 1-(MeNH2)(CN), and imine complex, 1-(MeN═CH2)2, respectively. Subsequent C-N bond formation was also observed in the latter upon addition of a coordinating ligand. Detailed computational studies support an alternating mechanism involving sequential N-H and C-H HAA to generate these unsaturated products.
