Syntheses of [60]Fullerene andN,N-Bis(4-biphenyl)aniline-Tethered Rotaxane: Photoinduced Electron-Transfer Processes via Singlet and Triplet States of [60]Fullerene
Visible‐Light‐Induced [4+2] Annulation of Thiophenes and Alkynes to Construct Benzene Rings
作者:Chunlan Song、Xin Dong、Zhongjie Wang、Kun Liu、Chien‐Wei Chiang、Aiwen Lei
DOI:10.1002/anie.201905971
日期:2019.8.26
The [4+2] annulation represents an elegant and versatile syntheticprotocol for the construction of benzene rings. Herein, a strategy for visible-light induced [4+2] annulation of thiophenes and alkynes, to afford benzene rings, is presented. Under simple and mild reaction conditions, the ready availability and structural diversity of thiophenes and alkynes permit the facile synthesis of several substituted
Spatial Anion Control on Palladium for Mild C–H Arylation of Arenes
作者:Jyoti Dhankhar、Elisa González-Fernández、Chao-Chen Dong、Tufan K. Mukhopadhyay、Anthony Linden、Ilija Čorić
DOI:10.1021/jacs.0c09611
日期:2020.11.11
C-H arylation of arenes without the use of directing groups is a challenge, even for simple molecules, such as benzene. We describe spatial anion control as a concept for the design of catalytic sites for C-H bond activation, thereby enabling nondirected C-H arylation of arenes at ambient temperature. The mild conditions enable late-stage structural diversification of biologically relevant small molecules
Palladium‐Catalyzed Secondary C(
<i>sp</i>
<sup>3</sup>
)−H Arylation of 2‐Alkylpyridines
作者:Hong‐Liang Li、Yoichiro Kuninobu
DOI:10.1002/adsc.202000306
日期:2020.7.16
A pyridyl group‐assisted palladium‐catalyzed secondary C(sp3)−H arylation protocol was developed. A substituent at the 3‐position of the pyridyl group is proved to be important for promoting C−H arylation and controlling the regioselectivity. Aryl iodides can be used as coupling partners. The reaction proceeded in good to excellent yields with good functional group tolerance, even on the gram‐scale
Palladium-Catalyzed Enantioselective C(sp<sup>3</sup>)–H Arylation of 2-Propyl Azaaryls Enabled by an Amino Acid Ligand
作者:Hong-Liang Li、Deng-Feng Yang、Hua-Qing Jing、Jon C. Antilla、Yoichiro Kuninobu
DOI:10.1021/acs.orglett.1c04215
日期:2022.2.18
A palladium(II)-catalyzed enantioselective arylation of unbiased secondaryC(sp3)–H bonds was developed. The enantioselectivity was controlled by the combination of a pyridyl or isoquinolinyl directinggroup and an amino acid, N-Boc-2-pentyl proline. A variety of 2-propyl azaaryls and biaryl iodides were employed to provide arylated products in moderate to good yields (up to 82%) with high enantioselectivities
4-[Di(biphenyl-4-yl)amino]azobenzene and 4,4′-bis[bis(4′-tert-butylbiphenyl-4-yl)amino]azobenzene as a novel family of photochromic amorphous molecular materials
We have created photochromic amorphous molecular materials containing an azobenzene chromophore, 4-[di(biphenyl-4-yl)amino]azobenzene and 4,4â²-bis[bis(4â²-tert-butylbiphenyl-4-yl)amino]azobenzene (t-BuBBAB), which readily form amorphous glasses above room temperature and exhibit photochromism in their amorphous films. We have shown that the photogenerated cis-form in the amorphous film can be stabilized at ambient temperature by the incorporation of a bulky group; the backward cisâtrans thermal isomerization can be controlled by temperature for t-BuBBAB.