A General Strategy Toward Aromatic 1,2-Ambiphilic Synthons: Palladium-Catalyzed ortho-Halogenation of PyDipSi-Arenes
作者:Alexander S. Dudnik、Natalia Chernyak、Chunhui Huang、Vladimir Gevorgyan
DOI:10.1002/anie.201004426
日期:2010.11.8
A general and efficient strategy to synthesize 1,2‐ambiphilic aromatic and heteroaromatic synthons from haloarenes has been developed. The method involves installation of the PyDipSi directing group, and subsequent palladium‐catalyzed directed ortho‐halogenation of aryl silanes (see scheme; Py=2‐pyridyl). The usefulness of these 1,2‐ambiphilic building blocks was shown in their participation as both
Amino acid-promoted C–H alkylation with alkylboronic acids using a removable directing group
作者:Yu Zhang、Hang Jiang、Dushen Chen、Yanghui Zhang
DOI:10.1039/c6ob00674d
日期:——
Palladium-catalyzed C–H alkylation reaction with alkylboronic acids has successfully been developed using a removable pyridyldiisopropylsilyl directing group. The amino acid played a crucial role as a ligand in the reaction. The alkylation protocol is also applicable to the coupling of C(sp3)–H bonds with alkylboronic acids.
PyDipSi: A General and Easily Modifiable/Traceless Si-Tethered Directing Group for C−H Acyloxylation of Arenes
作者:Natalia Chernyak、Alexander S. Dudnik、Chunhui Huang、Vladimir Gevorgyan
DOI:10.1021/ja1033167
日期:2010.6.23
A new general and easily installable silicon-tethered pyridyl-containing directing group (PyDipSi) that allows for highly efficient and regioselective Pd-catalyzed ortho C-H acyloxylation of arenes has been developed. It has also been demonstrated that this directing group can efficiently be removed as well as converted into a variety of other valuable functional groups. In addition, the installation of the PyDipSi directing group along with pivaloxylation and quantitative conversion of the PyDipSi group into a halogen functionality represents a formal three-step ortho oxygenation of haloarenes.