A study of molybdenum catalysts in the polymerization of 2,5-didodecyl-1,4-dipropynylbenzene

Investigation of molybdenum-based in situ catalyst systems for alkyne metathesis. The treatment of dipropynyldidodecylbenzene with a mixture of (acac)2MoO2 in the presence of 7 equivalents of triethylaluminum and 2-fluorophenol furnishes didodecyl-PPE of high molecular weight at temperatures as low as 105 °C in boiling toluene. A series of other molybdenum carbonyl complexes in the presence of phenols were as well investigated as metathesis catalysts. While all of the investigated catalyst precursors were active in the formation of PPEs, they are not more active than the original Mo(CO)6-4-chlorophenol system. The exception is the (acac)2MoO2-based catalyst that is significantly more active than all of the other investigated in situ catalyst systems.