R. Gleiter, R. Merger, B. Nuber
Nov 1, 1992
Citations
0
Influential Citations
26
Citations
Journal
Journal of the American Chemical Society
Abstract
The three skipped cyclic C 12 H 12 dienediynes, 4,9-dimethylene-1,6-cyclodecadiyne (1), (Z,Z)-4,10-cyclo-dodecadiene-1,7-diyne (2), and 10-methylene-(Z)-4-cycloundecene-1,7-diyne (3), have been synthesized by cyclization of dilithium salts of diterminal enediynes with the corresponding dihalogenides. This simple approach only worked (with approx. 5% yield) when no CuCl catalyst was used. Besides 1-3, 4,9-diisopropylidene-1,6-cyclodecadiyne(30), the cyclic enediynes (Z)-4-cycloundecene-1,7-diyne(19) and (Z)-4-cyclododecene-1,7-diyne (20), as well as 4-methylene-1,6-cyclodecadiyne (22), 4-methylene-1,6-cycloundecadiyne(23) and their isopropylidene congeners 25 and 28 have synthesized. Partial hydrogenation of 1-3 gives the corresponding homoconjugated tetrenes. The reaction of 30 with dicarbonyl(η 5 -cyclopentadienyl)cobalt yields a superphane of two cyclobutadiene units, stabilized by two CpCo moities