Neodymium allyl compounds

As the first catalytically active allyl-lanthanide compounds, the tetrakis(allyl) complexes Li[Ln(C3H5)4] dioxane, with Ln = Ce, Nd, Sm, Gd, and Dy, have been described [47]. More recently the field of allyl-lanthanide chemistry was extended considerably by the synthesis of the neutral tris(allyl) compounds of lanthanum and neodymium, LnlCsHj), n dioxane (Ln = La, n = 1.5 Ln = Nd, n = 1) from the tetrakis(allyl) complexes by abstraction of allyllithium with tri(ethyl)boron according to eqs. (1) and (2) [48]. For the catalytic properties of the allylneodymium(III) complexes, see [106],... 

Under standard conditions the tetrakis(allyl)neodymium complex, like the tris(allyl)neodymium complex, shows only moderate catalytic activity with a high trans selectivity, but in combination with appropriate Lewis acids such as alkylaluminum chlorides or methylalumoxane the activity can be increased considerably and the selectivity changes mainly to cis. Extremely active catalysts of very high cis selectivity are obtained with the chloro(allyl)neodymium compounds in combination with methylalumoxane in heptane. For more details see [39, 49, 106]. 

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