A novel palladium-catalyzed preparative method of α,β-unsaturated ketones and aldehydes from saturated ketones and aldehydes via their silyl enol ethers
作者:Jiro Tsuji、Ichiro Minami、Isao Shimizu
DOI:10.1016/s0040-4039(00)94160-1
日期:1983.1
Silyl enol ethers prepared from saturated ketones and aldehydes can be converted to α,β-unsaturated ketones and aldehydes by the reaction of allyl carbonate in the presence of palladium-phosphine complexes as a catalyst. The selection of solvent is crucial and nitriles are most effective as the solvent.
The PdII‐catalyzed dehydroboration of boron enolates generated from ketones and 9‐iodo‐9‐borabicyclo[3.3.1]nonane was achieved, providing a synthetically versatile protocol from ketones to α,β‐unsaturated ketones. The PdII compound employed in this reaction worked catalytically in the presence of Cu(OAc)2. The high trans‐selectivity of the olefinic moiety was observed. Aryl halide moieties (‐Br and
Catalytic asymmetric carbon–carbon bond formation using alkenes as alkylmetal equivalents
作者:Rebecca M. Maksymowicz、Philippe M. C. Roth、Stephen P. Fletcher
DOI:10.1038/nchem.1394
日期:2012.8
Catalytic asymmetric conjugate addition reactions with organometallicreagents are powerful reactions in synthetic chemistry. Procedures that use non-stabilized carbanions have been developed extensively, but these suffer from a number of limitations that prevent their use in many situations. Here, we report that alkylmetal species generated in situ from alkenes can be used in highly enantioselective
Palladium-catalyzed synthesis of α,β-unsaturated ketones from ketones via allyl enol carbonates
作者:Isao Shimizu、Ichiro Minami、Jiro Tsuji
DOI:10.1016/s0040-4039(00)81773-6
日期:——
Allylenol carbonates, prepared by quenching ketone enolates with allyl chloroformate, are converted to α,β-unsaturated ketones with Pd(OAc)2-dppe catalyst in CH3CN.
New synthetic methods for α,β -unsaturated ketones, aldehydes, esters and lactones by the palladium-catalyzed reactions of silyl enol ethers, ketene silyl acetals, and enol acetates with allyl carbonates
Silyl enol ethers and ketenesilylacetals derived from ketones, aldehydes, esters and lactones are converted into α,β-unsaturated ketones, aldehydes, esters and lactones by treatment with allyl carbonates in high yields using the palladium—bis(diphenylphosphino)ethane (dppe) complex as catalyst. Phosphine-free palladium catalyst instead of the palladium—phosphine complex gives a higher selectivity