Diolefins, telomerization

In the presence of suitable cocatalysts such as alcohols, phenols, or secondary amines, 1,3-diolefins are oligomerized to linear dimers or trimers by the same nickel-ligand systems, which are effective for cyclooligomerization (see 14.5.2.5.1). Reactions may be accompanied by telomerization. Typical examples are given in Table 1. 

Telomerization of Conjugated Diolefins with Aromatics and Olefins Using Chelated Organosodium Catalysts... 

A nionic telomerizations of conjugated diolefins with hydrocarbon acids - are known but suffer from very low catalytic efficiencies. Morton et al. (I) and, later, Pappas et al. (2) used unchelated organosodium compounds to telomerize conjugated diolefins with weak hydrocarbon acids but obtained very low catalyst efficiencies (about 5 grams/gram catalyst). More recently, the anionic telomerization of butadiene and toluene by sodium on oxide supports (3) and sodium in tetrahydrofuran (4) was studied .also, a potassium amide/lithiated alumina catalyst was used to telomerize butadiene (5). 

This report covers the use of chelated organosodium compounds as novel catalysts for telomerizing conjugated diolefins with weak hydrocarbon acids such as aromatics and olefins (7). The factors affecting the chain-transfer reaction were of particular interest because one of our objectives was to increase selectivity to low-molecular-weight species. The products are useful in synthesizing plasticizer alcohols, flame retardants, and surface coatings. 

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