An Iterative Method for the Synthesis of Symmetric Polyynes
作者:Racquel C. DeCicco、Allison Black、Lei Li、Nancy S. Goroff
DOI:10.1002/ejoc.201200442
日期:2012.9
An iterative synthetic route for obtaining symmetricpolyynes was developed, consisting of a series of iodination and Stille coupling reactions. The starting materials employed in this pathway are simple and can be prepared easily. Polyynes containing up to seven C≡C bonds were synthesized using this method. This route is particularly effective for accessing polyynes with an odd number of C≡C bonds
Synthesis and 13C NMR Spectroscopy of 13C-Labeled α,ω-Diphenylpolyynes
作者:Rik Tykwinski、Thanh Luu
DOI:10.1055/s-0031-1290983
日期:2012.6
The synthesis of three C-13-labeled alpha,omega-diphenylpolyynes is described. The known positions of the labeled carbon atoms allow assignment of the resonances in the C-13 NMR spectra and identification of trends in the chemical shifts.
Solution-spray flash vacuum pyrolysis: a new method for the synthesis of linear poliynes with odd numbers of C.tplbond.C bonds from substituted 3,4-dialkynyl-3-cyclobutene-1,2-diones
作者:Yves Rubin、Sophia S. Lin、Carolyn B. Knobler、John Anthony、Armen M. Boldi、Francois Diederich
DOI:10.1021/ja00018a035
日期:1991.8
We report a new method for the preparation of a wide range of linear poliynes, 1a-1i, with an odd number of C = C bonds. This method is based on solution-spray flash vacuum pyrolysis (SS-FVP) of the readily available 3,4-dialkynyl-3-cyclobutene-1,2-diones 3a-3i. It allows the synthesis of multigram quantities of a series of hexatriynes and decapentaynes from poorly volatile and thermally unstable precursors that cannot be subjected to conventional flash vacuum pyrolysis. Yields of the linear poliynes range from 42 to 99%. Similarly, the dodecahexayne 1j was obtained in 31% yield by SS-FVP of the bis(3-cyclobutene-1,2-dione) 3j. The synthesis of the new 3,4-dialkynyl-3-cyclobutene-1,2-diones 3h-3j via the ketals 7, 10, and 13 is reported. The X-ray crystal structure of 1,10-diphenyl-1,3,5,7,9-decapentayne (1c) was solved, and the crystal packing structure provides valuable information to explain the thermal polymerization behavior observed for this compound in the crystalline state.