PHOSPHINE-UREA LIGANDS FOR TRANSITION METAL CATALYZED CROSS-COUPLING REACTIONS
摘要:
Carbon-carbon bond forming reactions are the cornerstone of organic chemistry. A new class of ligands was developed for transition metal catalyzed cross-coupling reactions. These phosphine-urea ligands incorporate a urea subunit into the backbone of the ligand, which is designed to bind to the organometallic coupling partner and simultaneously facilitate and direct transmetalation of the nucleophile. Synthetic routes were designed and executed to synthesize phosphine-urea ligands. These ligands catalyze a wide variety of cross-coupling reactions including Suzuki, Negishi, and Buchwald-Hartwig cross-couplings. Aryl-aryl, alkyl-aryl, and alkyl-alkyl C—C cross-couplings are performed successfully with these ligands. In addition, specific chiral phosphine-urea ligands catalyze Negishi cross-couplings enantioselectively from a racemic alkylzinc nucleophile.
Compounds having the formula
1
are angiogenesis inhibitors. Also disclosed are compositions containing the compounds, methods of making the compounds, and methods of treatment using the compounds.
The invention relates to novel compounds for use as inhibitors of NLRP3 inflammasone production, wherein such compounds are as defined by compounds of formula (I) and wherein the integers R1, R2 and R3 are defined in the description, and where the compounds may be useful as medicaments, for instance for use in the treatment of a disease or disorder that is associated with NLRP3 inflammasome activity.
Ni<sup>I</sup>Catalyzes the Regioselective Cross-Coupling of Alkylzinc Halides and Propargyl Bromides to Allenes
作者:Rita Soler-Yanes、Iván Arribas-Álvarez、Manuel Guisán-Ceinos、Elena Buñuel、Diego J. Cárdenas
DOI:10.1002/chem.201603758
日期:2017.1.31
We describe the unprecedented formation of allenes by Ni‐catalyzed cross‐coupling of propargyl bromides with alkylzinc halides. The reaction regioselectivity is complementary to the previously reported formation of propargyl‐coupled compounds. Experiments support the formation of NiI complexes as the active species and the participation of radical intermediates. Kinetic studies showed that the reaction
Trimethylsilyl chloride promoted synthesis of α-branched amines by nucleophilic addition of organozinc halides to nitrones
作者:Ying Fu、Yanhua Liu、Yaojuan Chen、Helmut M. Hügel、Minzhu Wang、Danfeng Huang、Yulai Hu
DOI:10.1039/c2ob26202a
日期:——
general procedure for the nucleophilicaddition of organozinc halides with nitrones in the presence of trimethylsilyl chloride has been developed. Trimethylsilyl chloride was found to be both an indispensable reaction promoter and a ready hydroxylamine protective agent in these reactions. The produced O-(trimethylsilyl)hydroxylamines can be easily reduced into corresponding amines just by a zinc–copper
Pd-catalyzed Fukuyama cross-coupling of secondary organozinc reagents for the direct synthesis of unsymmetrical ketones
作者:Alan H. Cherney、Sarah E. Reisman
DOI:10.1016/j.tet.2013.11.104
日期:2014.5
organometallic reagents represents a convergent route toward complex and versatile ketone products. Despite the mild conditions and high functional group tolerance, the cross-coupling of carboxylic acid derivatives, such as thioesters, and secondary organometallic reagents is an underdeveloped transformation. Herein, we disclose a convenient and efficient protocol for the Pd-catalyzed Fukuyama cross-coupling