Allenes tris phosphite

Ni- and Rh-catalyzed intramolecular [4+2] cycloadditions of the diene-allene 65 using tri(o-phenylphenyl) phosphite gave the different products 66 and 67 [21],... 

Both bis(l,5-cyclooctadiene)nickel(0) and bis(acrylonitrile)nickel(0) catalyze the polymerization of allene to highly crystalline linear polymers (451). With compounds such as tri-o-tolyl phosphite, bis(acrylo-nitrile)nickel in hydrocarbon catalyzes the cyclodimerization of butadiene to 1,5-cyclooctadiene, whereas in alcohols it catalyzes the... 

The authors have also demonstrated that the chemoselective binding of the Rh catalyst to the allene r-system could be altered by changing the electronic property of the catalyst system. Employing tris(hexafluoro-2-propyl)phosphite as the additive, the Rh catal3rst selectively reacted with the terminal olefin of the allene 98 to furnish the 6-6-fiised ring product 99, which is analogous to the nickel-catalyzed reaction (97) (Scheme 50). 

Mixed catalytic oligomerization of butadiene and allene in the presence of nickel(0)-tris-(2-biphenylyl) phosphite provides (368) and (369) in 69% yield if a low concentration of allene is maintained. ... 

The mixed oligomerization of allene and butadiene (1 10) in the presence of nickel(o) tris(2-biphenylyl) phosphite affords the ten-membered ring [2+2+2] cycloadducts 284 and 285 in a combined yield of 69 %. Heating of the cycloadducts at 150 °C gives 4-methylene-c -divinylcyclohexane 286 as the result of a thermal Cope rearrangement . ... 

The nickel(0)-catalyzed stereoselective intramolecular [4+ 2] cycloaddition between dienes and unactivated allenes or alkynes has been shown to be an efficient complement to the uncatalyzed concerted Diels-Alder reaction that often requires stereoelectronic restrictions. In a typical reaction, treatment of dienyne with 10 mol% Ni(COD)2 and 30mol% of tri-o-biphenyl phosphite at room temperature... 

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