Abstract A variety of 1, 6-heptadiynes and certain borylalkynes co-oligomerize with enol ethers in the presence of [CpCo (C 2 H 4) 2](Cp= cyclopentadienyl) to furnish the hitherto elusive acyclic 2: 1 products, 1, 3, 5-trien-1-ol ethers, in preference to or in competition with the alternative pathway that leads to the standard [2+ 2+ 2] cycloadducts, 5-alkoxy-1, 3- cyclohexadienes. Minor variations, such as lengthening the diyne tether, cause reversion ...
