Parameters Influencing Reactivity and Regioselectivity in the Methoxycarbonylation of Arylalkenes
作者:Barend Bezuidenhoudt、Maretha du Plessis、Charlene Marais
DOI:10.1055/s-0035-1560912
日期:——
hydroformylation and hydroesterification reactions. However, little is known in this regard about the influence of the steric and electronic environment around the double bond of the substrate. A variety of arylalkenes were therefore subjected to methoxycarbonylation to investigate the steric and electronic effects of substituents on the aromatic ring of the substrate on the regioselectivity and reactivity in the
development of novel carbonylative transformations usingCOsurrogates. Consequently, toxic CO gas can be replaced by more convenient inorganic or organic carbonyl compounds. Herein, the first regioselectivemethoxycarbonylation of alkenes with paraformaldehyde and methanol as CO substitutes is reported. This new procedure is applicable to a series of alkenes in the presence of a palladium catalyst under
Recyclable Selective Palladium-Catalyzed Synthesis of Five-, Six- or Seven-Membered Ring Lactones and Lactams by Cyclocarbonylation in Ionic Liquids
作者:Fangguo Ye、Howard Alper
DOI:10.1002/adsc.200606100
日期:2006.9
ionic liquids, BMIMPF6 or BMIM NTf2, are used successfully for the palladium-catalyzed cyclocarbonylation of 2-allylphenols and anilines, 2-vinylphenols, and 2-aminostyrenes. The reaction proceeds cleanly and efficiently to afford high yields of lactones or lactams with good or excellent selectivity for one isomer. The ionic liquid containing the palladium catalyst, and ligand, is recyclable in all cases
Regioselective Palladium(II)-Catalyzed Synthesis of Five- or Seven-Membered Ring Lactones and Five-, Six- or Seven-Membered Ring Lactams by Cyclocarbonylation Methodology
作者:Bassam El Ali、Kazumi Okuro、Giuseppe Vasapollo、Howard Alper
DOI:10.1021/ja953403l
日期:1996.1.1
affording five- or seven-memberedring lactones (bicyclic, tricyclic, and pentacyclic) as the principal products, often in excellent yields. Use of 2-aminostyrenes as reactants and catalytic quantities of palladium acetate and tricyclohexylphosphine, affords five-membered ring lactams in high yield and selectivity. Bicyclic and tricyclic heterocycles containing six-membered ring lactams can be synthesized
A Palladium-Catalyzed Regioselective Hydroesterification of Alkenylphenols to Lactones with Phenyl Formate as CO Source
作者:Haining Wang、Ben Dong、Yang Wang、Jingfu Li、Yian Shi
DOI:10.1021/ol403171p
日期:2014.1.3
An effective Pd(OAc)2-PPh3 catalyzed hydroesterification of alkenylphenols with phenyl formate as CO surrogate is described. A variety of lactones are obtained in generally high yields with high regioselectivities. In one case, 76% ee is obtained with a chiral ligand.