1437769-72-6Relevant articles and documents
Access to Air-Stable 1,3-Diphosphacyclobutane-2,4-diyls by an Arylation Reaction with Arynes
Ueta, Yasuhiro,Mikami, Koichi,Ito, Shigekazu
, p. 7525 - 7529 (2016)
Tuning of the physicochemical properties of the 1,3-diphosphacyclobutane-2,4-diyl unit is attractive in view of materials applications. The use of arynes is shown to be effective for installing relatively electron rich aryl substituents into the open-shell singlet P-heterocyclic system. Treatment of the sterically encumbered 1,3-diphosphacyclobuten-4-yl anion with ortho-silylated aryl triflates in the presence of fluoride under appropriate conditions afforded the corresponding 1-aryl 1,3-diphosphacyclobutane-2,4-diyls. The air-stable open-shell singlet P-heterocycles exhibit considerable electron-donating character, and the aromatic substituent influences the open-shell character, which is thought to be related to the property of p-type semiconductivity. The P-arylated 1,3-diphosphacyclobutane-2,4-diyl systems can be further utilized as detectors of hydrogen fluoride (HF), which causes a remarkable change in their photoabsorption properties.
Ligand-Regulated Palladium-Catalyzed Regiodivergent Hydroarylation of the Distal Double Bond of Allenamides with Aryl Boronic Acid
Dong, Yunhui,Du, Xin,Li, Xinling,Liu, Hui,Liu, Qing,Wang, Ping,Zhang, Daopeng,Zhang, Lizhi,Zhao, Huan
, p. 13276 - 13288 (2021/10/12)
The ligand-regulated regiodivergent hydroarylation of the distal double bond of allenamides with aryl boronic acid was achieved in the presence of palladium(II) catalysts, delivering a variety of functionalized enamide with excellent E selectivity and Markovnikov/anti-Markovnikov selectivity. Two possible coordination intermediates were proposed to be responsible for the regiodivergent hydroarylation: (1) The coordination Intermediate I, which was proposed to be formed through the coordination of MeCN, distal double bond, phenyl to palladium, led to the aryl group away from the Intermediate I, inducing excellent E selectivity and anti-Markovnikov selectivity. (2) A switch of regioselectivity to 1,2-Markovnikov hydroarylation was obtained using bidentate phosphine ligand (dppf or Xantphos). The formed coordination Intermediate II led to the N-tether away from the Intermediate II and at the trans position of aryl, resulting in excellent E selectivity and Markovnikov selectivity. Meanwhile, tentative investigation on the mechanism proved that the hydron source of this hydroarylation is more likely to be boronic acid. The transmetallation between aryl boronic acid and palladium catalyst was the initial step of this transformation.
2-[(Neopentyl glycolato)boryl]phenyl Triflates and Halides for Fluoride Ion-Mediated Generation of Functionalized Benzynes
Ikawa, Takashi,Yamamoto, Rika,Takagi, Akira,Ito, Toyohiro,Shimizu, Kazunori,Goto, Masahiko,Hamashima, Yoshitaka,Akai, Shuji
, p. 2287 - 2300 (2015/07/27)
2-[(Neopentyl glycolato)boryl]phenyl trifluoromethanesulfonates (triflates) and halides have been developed as new benzyne precursors, which generate benzynes at 120°C in the presence of a fluoride ion. There are two major features of these types of precu
Generation of arynes via ate complexes of arylboronic esters with an ortho-leaving group
Sumida, Yuto,Kato, Tomoe,Hosoya, Takamitsu
, p. 2806 - 2809 (2013/07/11)
An efficient method of generating aryne has been achieved by treating ortho-(trifluoromethanesulfonyloxy)arylboronic acid pinacol ester with tert- or sec-butyllithium. Monitoring the reaction by 11B NMR has indicated that a boron-ate complex formed in situ is the eventual precursor that converts into aryne near room temperature. The prior formation of the ate complex at a low temperature has enabled us to use various arynophiles, including those bearing base-sensitive groups. The ready availability of the aryne precursors and mutual orthogonality in aryne generation with widely used ortho-silylaryl triflate have enhanced the utility of the method.
