42550-76-5Relevant academic research and scientific papers
Mechanistic studies on Pd-catalyzed telomerization and co-cyclization of butadiene: Amphiphilicity of bis-π-allylpalladium intermediate in the presence of phosphine ligand
Kiji, Jitsuo,Okano, Tamon,Nomura, Takaaki,Saiki, Kayoko,Sai, Torei,Tsuji, Jiro
, p. 1939 - 1945 (2007/10/03)
Pd-catalyzed reactions of butadiene, which proceed through a bis-π-allylpalladium intermediate, (η3,η3-C8H12)Pd (2), were performed in the presence of both a pronucleophile (aceto- or cyanoacetate) and an electrophile (benzaldehyde). Methyl aceto- or cyanoacetate and benzaldehyde reacted independently with 2 to give telomers 8 and the divinylsubstituted pyranes 9, respectively. In the case of methyl cyanoacetate, the co-cyclization of 2 with 2-cyano-3-phenylpropenoate (11) formed in situ also took place to afford the cyclohexane derivative 10. Namely, three kinds of amphiphilic additions of the C8-chain of 2 occurred to δ+H-Nuδ-, δ+C=Cδ- and δ+C=Oδ- simultaneously in a one-pot reaction The Pd-catalyzed reaction of allyl chloride, allyltributylstannane, methyl cyanoacetate, and benzaldehyde was undertaken under neutral conditions, expecting the amphiphilic reactions by the intermediacy of (η3-C3H5)2Pd (6) formed in situ. Allylation of both benzaldehyde and methyl cyanoacetate took place. Competitively amphiphilic bis-allylation of the polar double bond of 11 also occurred to form the 1,7-octadiene derivative 18. The mechanisms of both reactions can be explainable in terms of the amphiphilicity of the intermediates (2 and 6) in the presence of a phosphine ligand.
