Jitsuo Kiji

Nickel-catalyzed allyl-transfer reactions

Abstract The reaction of allylic compounds in the presence of some nickel catalysts has been studied. 2,7-Octadienyl isopropyl ether is converted into 2-methylenevinylcyclopentane in moderate yield by NiX2(n-Bu3P)2-t-BuOK (1:2) (where X is Cl, Br, or NO3) in ethanol. In amines the hydroxyl or ether group of allyl compound is smoothly substituted with the amino group; corresponding allyl substituted amines are formed in high yields. Allyl alcohol is selectively converted to diallyl ether in the presence of Ni(Acac)2-n-Bu3P-NaBH4 (1:3:1) at 40°C. At higher temperature isomerization of allyl alcohol into propionaldehyde is predominate. These reactions are considered to proceed through π-allyl intermediates.

Reaction of 2-t-butyl-1,3-butadiene with π-allylic palladium complexes. A novel cyclization of allylilc ligands

Abstract The reaction of 2-t-butyl-1,3-butadiene with π-allylic palladium chlorides is described. The 2-chloroallyl complex gives a π-allylic complex with an open chain structure, in which the butenyl group in is the anti-position. Allyl-1-carbomethoxyallyl-, methallyl-, and 1-carbomethoxymethallyl-palladium chlorides give six-membered cyclic complexes. The product of the former two are π-allyllic and those of the latter are σ-bonded complexes.

A NOVEL DIMERIZATION OF NORBORNADIENE BY NICKEL CATALYSTS

Abstract In amine norbornadiene is converted catalytically into exo -5-(o- tolyl) - 2 - norbornene by (n-Bu3P)2NiX2- NaBH4 (where X is anionic ligand: e.g., Br, Cl, or SCN), the ratio of which is less than 1. Addition of more amount of NaBH4 leads to the formation of [2+2] cycloaddition products.

Homogeneous Catalysis of Nickel Complexes. Oligomerization, Polymerization and Some Related Reactions of Diolefins

It has already been reported that the cyclodimerization of butadiene proceeds smoothly under the influence of some nickel complexes to give 2-methylenevinylcyclopentane (I) ((a), Eq. 1).1 In this reaction a ligand-containing nickel(0) complex, combined with protic acid, has been proved to be an active species.2 Not only the cyclodimerization but also following reactions of diolefins occur in the presence of the catalysts; (b) trans-l,14-polymerization,3 (c) amination of 1,3-diolefin and norbornadiene,4 (d) ally1 transfer,5 (e) a novel dimerization of norbornadiene (Eq.2),6 and (f) cycloaddition of butadiene to strained ring olefins to form an exomethylene- and methyl-substituted four-membered cyclic compound (Eq. 3).7