Palladium-Catalyzed Regiodivergent Substitution of Propargylic Carbonates
作者:Theresa M. Locascio、Jon A. Tunge
DOI:10.1002/chem.201603481
日期:2016.12.12
The palladium(0)‐catalyzed, ligand‐controlled, regioselective addition of diaryl acetonitrile pronucleophiles to propargylic carbonates is reported. Selective formation of either terminal 1,3‐dienyl or propargylated products is proposed to arise from a change in reaction mechanism controlled by the denticity of the coordinating ligand.
Palladium-Catalyzed Direct α-Arylation of Arylacetonitriles with Aryl Tosylates and Mesylates
作者:On Ying Yuen、Xiangmeng Chen、Junyu Wu、Chau Ming So
DOI:10.1002/ejoc.202000176
日期:2020.3.31
The first general palladium‐catalyzed α‐arylation of arylacetonitriles with aryl and heteroaryl sulfonates are reported. The catalyst system comprising of Pd(OAc)2 and XPhos is highly effective towards this reaction. A wide range of aryl/heteroaryl tosylates and mesylates are coupled with arylacetonitriles smoothly and catalyst loadings as low as 0.1 mol‐% Pd can be achieved.
Divergent Synthesis of Isonitriles and Nitriles by Palladium-Catalyzed Benzylic Substitution with TMSCN
作者:Kento Asai、Koji Hirano、Masahiro Miura
DOI:10.1021/acs.joc.0c01861
日期:2020.10.2
Ligand-controlled palladium-catalyzed divergent synthesis of isonitriles and nitriles from benzylic carbonates and TMSCN has been developed. The BINAP- or DPEphos-ligated palladium catalyst selectively provides the corresponding benzylic isonitriles, whereas their regioisomers, benzylic nitriles, are formed exclusively under phosphine ligand-free conditions. Mechanistic studies reveal that isonitrile
The Pd/PMe3-catalyzed allylation of 1-(cyanomethyl)naphthalenes with allyl acetates proved to be para- rather than α-regioselective. This reaction is thought to proceed through ligand attack of the para-carbon in the arenes, electronically enriched by a cyano-stabilized α-carbanion, to the (π-allyl)palladium and a 1,5-hydrogen shift of the para-hydrogen from the dearomatized intermediate.