Enantioselective Construction of Spiro Quaternary Carbon Stereocenters via Pd-Catalyzed Intramolecular α-Arylation
摘要:
We herein report the development of a sterically hindered and electron-rich P-chiral monophosphorus biaryl ligand that has enabled a general and efficient enantioselective intramolecular alpha-arylation, providing access to a wide series of [4.4], [4.5], and [4.6]-spirocycles with chiral benzylic quaternary carbons in high yields with good to excellent enantioselectivities. A pronounced water effect on enantioselectivity is observed.
Alkenyl Arenes as Dipolarophiles in Catalytic Asymmetric 1,3-Dipolar Cycloaddition Reactions of Azomethine Ylides
作者:Ana Pascual-Escudero、Abel de Cózar、Fernando P. Cossío、Javier Adrio、Juan C. Carretero
DOI:10.1002/anie.201609187
日期:2016.12.5
The use of alkenyl arenes as dipolarophiles in the catalytic asymmetric 1,3‐dipolarcycloaddition of azomethineylides is reported. Under appropriate reaction conditions with a CuI or AgI catalyst either the exo or the endo adduct was obtained with high stereoselectivity. This process provides efficient access to highly enantiomerically enriched 4‐aryl proline derivatives. The observed results are
Direct synthesis of dialkylarylvinylsilane derivatives: metathesis of dialkylaryl-iso-propenylsilane and its application to tetracyclic silacycle dye synthesis
The metathesis of dialkylarylvinylsilane, which has not been accomplished to date, is achieved using dialkylaryl-iso-propenylsilane as a substrate. In addition, we discovered that the reason why the metathesis of a ruthenium carbene complex and dialkylarylvinylsilane is difficult is the formation of a carbide complex.
and regioselective vicinal dioxidation of alkenes under transition metal and organic peroxide free conditions has been developed. This approach uses N-hydroxyphthalimide and its analogues as the transient nitroxyl-radical precursors and 2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (TEMPO+BF4–) as the oxidant as well as the source of persistent nitroxide. By employing this method, multifarious
Regioselective Three-Component Synthesis of Vicinal Diamines via 1,2-Diamination of Styrenes
作者:Jie Cao、Daqi Lv、Fei Yu、Mong-Feng Chiou、Yajun Li、Hongli Bao
DOI:10.1021/acs.orglett.1c00898
日期:2021.4.16
The vicinal diamine motif plays a significant role in natural products, drug design, and organic synthesis, and development of synthetic methods for the synthesis of diamines is a long-standing interest. Herein, we report a regioselective intermolecular three-component vicinal diamination of styrenes with acetonitrile and azodicarboxylates. The diamination products can be produced in moderate to excellent
Microwave-Enhanced Carbonylative Generation of Indanones and 3-Acylaminoindanones
作者:Xiongyu Wu、Peter Nilsson、Mats Larhed
DOI:10.1021/jo048375g
日期:2005.1.1
incomplete conversions of sluggish o-styryl bromides and chlorides were realized. Internal and chemoselective palladium(0)-catalyzed Heck arylations of enamides afforded suitable starting materials for subsequent rapid ring-closing reactions. Microwave-heated intramolecular in situ carbonylation of these electron-rich and sterically congested olefins conveniently afforded eight functionalized 3-acylaminoindanone