functionalizations of more distal C-H bonds in hydrocinnamoyl ketones, Weinreb amides, and biphenyl Weinreb amides. Mechanistically, the coordination of these carbonyl groups and the bisdentate amino acid ligand with Pd(II) centers provides further evidence for our early hypothesis that the carbonyl groups of the potassium carboxylate are responsible for the directed C-H activation of carboxylicacids.
Octahedral iridium complex catalyzed α-chlorination of 2-acyl imidazoles with tosyl chloride
作者:Tao Deng、Pranjal P. Bora、Shao-Xia Lin、Yi Li、Qiang Kang
DOI:10.1016/j.tetlet.2017.01.078
日期:2017.3
An efficient and catalytic α-chlorination of 2-acyl imidazoles with readily available tosyl chloride catalyzed by an octahedral iridiumcomplex under mild condition was reported. A range of 2-acyl imidazoles were converted to their corresponding α-chlorination products in good to excellent yields.
Nickel-Catalyzed Asymmetric Intramolecular Reductive Heck Reaction of Unactivated Alkenes
作者:Feiyan Yang、Youxiang Jin、Chuan Wang
DOI:10.1021/acs.orglett.9b02577
日期:2019.9.6
An asymmetric Ni-catalyzed intramolecular reductiveHeckreaction of unactivated alkenes tethered to aryl bromides has been accomplished, providing a variety of benzene-fused cyclic compounds bearing a quaternary stereogenic center in good to excellent yields and high enantioselectivities. A mechanism has been proposed, which involves the enantiodetermining migratory insertion and the following protonation
The stereochemical course of intramolecularcarbolithiation of alkynes was, experimentally and computationally, investigated for the stereocontrolled preparation of alkylidene indenols. Reversal of syn-carbolithiation to anti-carbolithiation is observed in the presence of a lithium-chelating propargylic substituent. Electrophile trapping and domino process give access to tetrasubstituted compounds
Silyl-naphthalene endoperoxides as switchable sources of singlet oxygen for bactericidal activity
作者:Min Qu、Nan Wu、Wanqing Jiang、Lei Wang、Mahinur S. Akkaya、Engin U. Akkaya
DOI:10.1039/d1ra02933a
日期:——
“caged” structure, in the form of an endoperoxide. Here, the trimethylsilyl (TMS) group supplies the steric bulk, inhibiting the cycloreversion reaction to produce very little singlet oxygen under ambient conditions. However, when fluoride ions are added as tetrabutylammoniumfluoride, very rapid removal of the TMS group takes place, followed by the unhindered cycloreversion, releasing singlet oxygen