Structural studies, lead compounds donor groups

Goates, Ott, et al. have rationalized their extensive data by suggesting that a cyclic structure for the second component is an important factor leading to compound formation. Carbon disulphide appears to be the only non-cyclic substance so far studied that forms a compound with CeF. The presence of multiple interaction sites on the donor molecule is also seen to be important. The stability of the compounds is enhanced as the number of active groups C=C double bonds, 0-atoms, or N-atoms, is increased. The suggestion that the existence of these solid compounds is due to donor-acceptor complexing can be discounted when it is noted that triethylamine, JVJV-dimethylacetamide, tetra-hydrofuran, and 1,2-dimethoxyethane do not form compounds with C F but are as efficient electron donors as many of the cyclic molecules listed in Table 6. 

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