| abstract |
Diethers of general formula: <CHEM> where R, R<I>, R<II>, R<III>, R<IV> and R<V>, same or different, are H or linear or branched alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl radicals with 1-18 carbon atoms, provided that R and R<I> are not both H or CH3 or are not CH3 and n-propyl; R<VI> and R<VII> the same or different, are linear or branched alkyl, cycloaliphatic, aryl, or arylalkyl radicals having 1-18 carbon atoms; one or more of R to R<VII> may be bonded to form a cyclic structure. The diethers are particularly useful in the preparation of Ziegler-Natta catalysts. |