Cyclopentadienyl triphenylphosphine cobalt with Various Substituents

3-BUTADIENE-l,4-DIYL)(i -CYCLOPENTADIENYL)-(TRIPHENYLPHOSPHINE)COBALT WITH VARIOUS SUBSTITUENTS 

The f -cyclopentadienylcobalt unit, [Co( -C5H5)], is believed to be a key active species in catalytic cyclooligomerization of acetylenes or cooligomerization of acetylenes with other unsaturated reactants. It can be generated from several precursors, [Co( j -CjH5)(CO)2], [Co(i -CsH5)( -diene)],  

When disubstituted acetylenes are employed, the i/ -acetylene complex, [Co( / -C5H5)(PPh3)(RC=CR)], can be isolated. In such cases, one can construct a cobaltacyclopentadiene with two different acetylene units by addition of other acetylenes, or one can synthesize cobaltacyclopentene complexes by addition of olefins. 

An effort to get more crystals from the mother liquid is often unsuccessful. Yield 9.9-13 g (53-69%). For analytical purpose the product is recrystallized from toluene-hexane. 

Into a 200-mL single-necked flask fitted with a nitrogen bypass and equipped with a magnetic stirring bar is placed Co t) - 

(n5-CYCLOPENTADIENYL)[l, l -(i 2-l,2-ETHYNEDIYL)DI-BENZENE](TRIPHENYLPHOSPHINE)COBALT AND (q5-CYCLOPENTADIENYL) (METHYL 3-PHENYL-q2-2-PROPYNOATE)(TRIPHENYLPHOSPHINE)COBALTt 

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