π-アリルモリブデン触媒によるアルキン類の環化反応に関する知見　

抄録

Low-valent molybdenum complexes showed similar reactivity typically in the Pauson-Khand-type reactions with their cobalt complexes. However, these two categories of metal complexes showed completely different feature in the catalytic reaction. While dicobalt octacarbonyl with certain activator catalyzed the intramolecular Pauson-Khand reaction, one of the low-valent molybdenum complexes, π-allylmolybdenum, did not catalyzed the desired reaction but produced cyclohexadiene derivatives as a major component even under pressured CO atmosphere. This trend in cyclization clearly appeared when 1,7-diphenyl-1,6-heptadiynes were used as substrate. Cyclopentadienone derivatives were produced when dicobalt octacarbonyl was used as a catalyst, whereas substituted benzene derivatives were produced when π-allylmolybdenum was used in the presence of excess allyl bromide.

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