Synthesis and characterization of cyclobutenedione–bithiophene π-conjugated polymers: acetal-protecting strategy for Kumada–Tamao–Corriu coupling polymerization between aryl bromide and Grignard reagents
Kumada–Tamao–Corriu coupling polymerization of a cyclobutenedione monomer whose carbonyl groups are protected as acetals was achieved. Hydrolysis of the acetals afforded donor–acceptor type π-conjugated polymers consisting of cyclobutenedione as an acceptor unit and bithiophene as a donor unit. The acetal-protected monomer was also subjected to Suzuki–Miyaura coupling polymerization. The absorption and emission
Reaction of Dimethoxycarbene−DMAD Zwitterion with 1,2-Diones and Anhydrides: A Novel Synthesis of Highly Substituted Dihydrofurans and Spirodihydrofurans
The zwitterion formed by the reaction of dimethoxycarbene and DMAD adds efficiently to one of the carbonyl groups of 1,2-dicarbonyl compounds and anhydrides to generate dihydrofurans and spirodihydrofurans in good yields. In many cases, the carbene inserts into the C−C bond of the dione to yield masked vicinal tricarbonyl systems.
Engaging the Pyridine-DMAD Zwitterion in a Novel Strategy for the Selective Synthesis of Highly Substituted Benzene and Cyclopentenedione Derivatives
作者:Vijay Nair、Abhilash N. Pillai、P. B. Beneesh、Eringathodi Suresh
DOI:10.1021/ol051723w
日期:2005.10.1
[reaction: see text] The pyridine-mediated reaction of dimethylacetylenedicarboxylate and cyclobutene-1,2-diones affords selective access to either hexasubstituted benzene derivatives or cyclopentenedione derivatives depending on the concentration of pyridine.