作者:Aditya L. Gottumukkala、Kiran Matcha、Martin Lutz、Johannes G. de Vries、Adriaan J. Minnaard
DOI:10.1002/chem.201200694
日期:2012.5.29
An efficient palladium catalyst is presented for the formation of benzylic quaternarystereocenters by conjugate addition of arylboronic acids to a variety of β,β‐disubstituted carbocyclic, heterocyclic, and acyclic enones. The catalyst is readily prepared from PdCl2, PhBOX, and AgSbF6, and provides products in up to 99 % enantiomeric excess, with good yields. Based on this strategy, (−)‐α‐cuparenone
Disclosed herein are compounds of formula (I) or pharmaceutically acceptable salts, solvates, or combinations thereof,
wherein X
1
, X
2
, X
3
, X
4
, J, K, L, X
5
, X
6
, R
b
, G
2
, and m are defined in the specification. Compositions comprising such compounds and methods for treating conditions and disorders using such compounds and compositions are also disclosed.
Synthesis of diverse β-quaternary ketones via palladium-catalyzed asymmetric conjugate addition of arylboronic acids to cyclic enones
作者:Jeffrey C. Holder、Emmett D. Goodman、Kotaro Kikushima、Michele Gatti、Alexander N. Marziale、Brian M. Stoltz
DOI:10.1016/j.tet.2014.11.048
日期:2015.9
The development and optimization of a palladium-catalyzedasymmetricconjugateaddition of arylboronicacids to cyclic enone conjugateacceptors is described. These reactions employ air-stable and readily-available reagents in an operationally simple and robust transformation that yields β-quaternary ketones in high yields and enantioselectivities. Notably, the reaction itself is highly tolerant of
Recoverable polystyrene-supported palladium catalyst for construction of all-carbon quaternary stereocenters via asymmetric 1,4-addition of arylboronic acids to cyclic enones
we describe the preparation of a recoverable polystyrene supported chiral palladium catalyst based on PyOx ligand suitable for asymmetric 1,4-addition of arylboronic acids to cyclic 3-substituted five- and six-memberedenones. In the reaction, all‑carbon quaternary stereocenters are formed with a high level of enantioselectivity (up to 91% ee) and conversion (up to 99%). The catalyst was used in 6 cycles
Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Five-, Six-, and Seven-Membered β-Substituted Cyclic Enones: Enantioselective Construction of All-Carbon Quaternary Stereocenters
作者:Kotaro Kikushima、Jeffrey C. Holder、Michele Gatti、Brian M. Stoltz
DOI:10.1021/ja200664x
日期:2011.5.11
The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4-addition of arylboronic acids to β-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF(3))(2) and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this