Three-component synthesis of 2-(4-amino-2,5-dihydro-1H-imidazol-5-ylidene)malononitriles
摘要:
2-(4-Amino-2,5-dihydro-1H-imidazol-4-yildene)malononitriles were synthesized by three-component reaction of tetracyanoethylene, carbonyl compound, and ammonium acetate. The synthesis can be performed in two steps with intermediate isolation of 2-aminoethene-1,1,2-tricarbonitrile, as well as using preliminarily prepared 2-aminoethene-1,1,2-tricarbonitrile and 1,3,5-trisubstituted 2,4-diazapentadienes.
Unlocking Acyclic π-Bond Rich Structure Space with Tetraethynylethylene–Tetravinylethylene Hybrids
作者:Kelsey L. Horvath、Nicholas L. Magann、Madison J. Sowden、Michael G. Gardiner、Michael S. Sherburn
DOI:10.1021/jacs.9b08885
日期:2019.12.18
Literature reports describe tetraethynylethylene (TEE) as unstable but tetravinylethylene (TVE) as stable. The stabilities of these two known compounds are reinvestigated, along with those of five unprecedented TEE-TVE hybrid compounds. The five new C10 hydro-carbons possess a core, tetrasubstituted C=C bond carrying all possible combinations of vinyl and ethynyl groups. A unified strategy is described
investigations (Table) demonstrated that the radiaannulenes are particularly powerful electronacceptors. Thus, bicyclic radiaannulene 11, which possesses eight peripheral 3,5-di(tert-butyl)phenyl substituents, is reversibly reduced at −0.83 V in THF (vs. Fc+/Fc), making it a betterelectronacceptorthan buckminsterfullerene C60 under comparable conditions.
Synthesis of a Series of Diiron Complexes Based on a Tetraethynylethene Skeleton and Related C<sub>6</sub>-Enediyne Spacers, (dppe)Cp*Fe−C⋮CC(R)C(R)C⋮C−FeCp*(dppe): Tunable Molecular Wires
complexes as molecularwires has been evaluated on the basis of the comproportionation constants (KC) obtained by electrochemical measurements and the Vab values obtained from the spectral parameters of the intervalence charge transfer bands of the isolated monocationic radical species appearing in the near-IR region. As a result, the C6-enediyne complexes turn out to be excellent molecularwires, with KC
一系列带有FeCp *(dppe)(Fe)端盖的3,4-二取代的(hex-3-ene-1,5-diyne-1,6-diyl)diron配合物Fe -C⋮CC(C)C (R)C⋮C- Fe(R = H,C⋮C-SiMe 3,C⋮C-H,C 6 H 5,p -C 6 H 4 CF 3),以及相关的(octa-3,5二烯-1,7-二炔-1,8-二基)diron络合物,铁-C⋮C-C(H)C(H)C(H)C(H)C⋮C-铁,已经被制备并评估了它们作为分子丝的性能。烯炔配合物是通过亚乙烯基中间体[ Fe C C(H)C(R)C(R)C(H)合成的衍生自相应的末端炔烃或Me 3 Si保护的前体(XC⋮CCC(C)C⋮C-X; X = H,SiMe 3)的C Fe ] 2+,其产品已经在光谱学和结晶学上表征。基于通过电化学测量获得的配分常数(K C)和从分离的单阳离子自由基的间隔电荷转移带的光谱参数获得的V
Tetraethynylethenes: Fully cross-conjugated ?-electron chromophores and molecular scaffolds for all-carbon networks and carbon-rich nanomaterials
作者:John Anthony、Armen M. Boldi、Yves Rubin、Markus Hobi、Volker Gramlich、Carolyn B. Knobler、Paul Seiler、Fran�ois Diederich
DOI:10.1002/hlca.19950780104
日期:1995.2.8
isolated in pure form, whereas derivatives with two or more free CH termini were only stable in dilute solution and polymerized rapidly in pure form. A trans-bis(triisopropylsilyl)-protected derivative represented an exception and could be isolated as stable crystals. X-Ray analysis revealed that the two bulky (i-Pr)3Si groups isolate the reactive chromophores from one another in the crystal and prevent