An Improved Synthesis of Cyclic Dialkynes

Synthesis and transformations of metallacycles 36. Cycloalumination of macrocyclic diacetylenes with Et3Al catalyzed by Cp2ZrCl2

“…The reactions were studied on the example of symmetrical cyclic diynes, cyclododeca 1,7 diyne (1a), cyclotetradeca 1,8 diyne (1b), and cyclohexadeca 1,9 diyne (1c). 23 Herein, based on the results obtained previously on cycloalumination of disubstituted acetylenes, 3 we devel oped conditions (cycloalkadiyne : Et 3 Al : [Zr] = 1 : 6 : 0.1, 20-22 °C, hexane, 6 h) for cycloalumination of cyclotet radeca 1,8 diyne (1b) as a model compound. Under these conditions, 1b underwent cycloalumination involving both triple bonds to give isomeric tricyclic bisaluminacyclo pentenes 2b and 3b in the ratio of 1 : 1 in 91% total yield (Scheme 2).…”

Synergetic Effects of Oxidative and Coordinative Promotors to Increase the Yield of a Twofold Pauson−Khand Reaction

“…The starting materials were prepared according to literature methods. [21] If not otherwise noted, the products were diastereomeric mixtures of the tricyclic diones.…”

Syntheses of double- and triple-decker clusters of osmium and cobalt metals linked by cyclotetradeca-1,8-diyne ligands

“…Cyclotetradeca-1,8-diene (C 14 H 20 ) [11], Os 3 (CO) 10 (NCMe) 2 [12], Os 3 (CO) 10 (C 14 H 20 ) (1) [5], Os 3 (CO) 9 (C 28 H 40 ) (2) [5], and Os 3 (CO) 8 (C 14 H 20 ) 2 (3) [6] were prepared by literature methods. Co 2 (CO) 8 (from Strem) was used as received.…”