163271-80-5Relevant articles and documents
Straightforward Synthesis of 5-Bromopenta-2,4-diynenitrile and Its Reactivity Towards Terminal Alkynes: A Direct Access to Diene and Benzofulvene Scaffolds
Kerisit, Nicolas,Toupet, Lo?c,Larini, Paolo,Perrin, Lionel,Guillemin, Jean-Claude,Trolez, Yann
, p. 6042 - 6047 (2015)
The high-yielding synthesis of 5-bromopenta-2,4-diynenitrile (BrC5N) was achieved for the first time. Its reactivity with triisopropylsilylacetylene and triisopropylsilylbutadiyne in the presence of copper and palladium as co-catalysts and diisopropylamine was evaluated. It revealed an unprecedented cascade reaction leading to a diene in one case and to a benzofulvene in the other case, with a unique structure. Both of them were characterized by X-ray crystallography, among other techniques. The mechanism of the reaction leading to the diene was investigated experimentally. Theoretical calculations at the DFT level suggest that the mechanism leading to the benzofulvene relies on a hexa-dehydro Diels-Alder (HDDA)-type of mechanism. This work constitutes an example of an unanticipated reactivity leading to an important increase of chemical complexity.
Synthesis of Polyynes Using Dicobalt Masking Groups
Kohn, Daniel R.,Gawel, Przemyslaw,Xiong, Yaoyao,Christensen, Kirsten E.,Anderson, Harry L.
, p. 2077 - 2086 (2018)
Extended triisopropylsilyl end-capped polyynes have been prepared from the corresponding tetracobalt complexes by removing the complexed dicobalt tetracarbonyldiphenylphosphinomethane (Co2(CO)4dppm) moieties. Unmasking of this "masked alkyne equivalent" was achieved under mild conditions with elemental iodine at room temperature, making it possible to obtain fragile polyynes with up to 20 contiguous sp-hybridized carbon atoms. The Co2(CO)4dppm moiety has a strong geometric and steric effect on the polyyne but does not have a marked electronic effect on the terminal alkyne, as indicated by NMR and IR spectroscopy, density functional theory calculations, and X-ray crystallography. An unusual "alkyne hopping" migration of the dicobalt group was noticed as a minor side reaction during copper-catalyzed Eglinton coupling.
Novel one-pot synthesis of 5-alkenyl-15-alkynylporphyrins and their derivatisation to a butadiyne-linked benzoporphyrin dimer
Yamada, Hiroko,Kushibe, Kayo,Okujima, Tetsuo,Uno, Hidemitsu,Ono, Noboru
, p. 383 - 385 (2006)
5-Alkenyl-15-alkynylporphyrins have been obtained unexpectedly by [2 + 2] acid-catalyzed condensation of dipyrrylmethane and TMS propynal in addition to 5,15-dialkynylporphyrin, and the unsymmetrical porphyrin can be converted to a butadiyne-linked dimer
carbo-Naphthalene: A Polycyclic carbo-Benzenoid Fragment of α-Graphyne
Cocq, Kévin,Saffon-Merceron, Nathalie,Coppel, Yannick,Poidevin, Corentin,Maraval, Valérie,Chauvin, Remi
, p. 15133 - 15136 (2016)
A ring carbo-mer of naphthalene, C32Ar8(Ar=p-n-pentylphenyl), has been obtained as a stable blue chromophore, after a 19-step synthetic route involving methods inspired from those used in the synthesis of carbo-benzenes, or specifically devised for the present target, like a double Sonogashira-type coupling reaction. The last step is a SnCl2/HCl-mediated reduction of a decaoxy-carbo-decalin, which is prepared through successive [8+10] macrocyclization steps. Two carbo-benzene references are also described, C18Ar6and o-C18Ar4(C≡C-SiiPr3)2. The carbo-naphthalene bicycle is locally aromatic according to structural and magnetic criteria, as revealed by strong diatropic ring current effects on the deshielding of1H nuclei of the Ar groups and on the negative value of the DFT-calculated NICS at the center of the C18rings (?12.8 ppm). The stability and aromaticity of this smallest fused molecular fragment of α-graphyne allows prediction of the same properties for the carbon allotrope itself.
Substituted Tetraethynylethylene–Tetravinylethylene Hybrids
Connor, Kieran P. E.,Horvath, Kelsey L.,Magann, Nicholas L.,Sherburn, Michael S.,Sowden, Madison J.,Westley, Erin
supporting information, p. 977 - 986 (2022/02/03)
A general synthetic approach to molecular structures that are hybrids of tetraethynylethylene (TEE) and tetravinylethylene (TVE) is reported. The synthesis permits the controlled preparation of many previously inaccessible structures, including examples w
A Practical, Component-Based Synthetic Route to Methylthiolincosamine Permitting Facile Northern-Half Diversification of Lincosamide Antibiotics
Mitcheltree, Matthew J.,Stevenson, Jack W.,Pisipati, Amarnath,Myers, Andrew G.
supporting information, p. 6829 - 6835 (2021/05/29)
The development of a flexible, component-based synthetic route to the amino sugar fragment of the lincosamide antibiotics is described. This route hinges on the application and extension of nitroaldol chemistry to forge strategic bonds within complex amino sugar targets and employs a glycal epoxide as a versatile glycosyl donor for the installation of anomeric groups. Through building-block exchange and late-stage functionalization, this route affords access to a host of rationally designed lincosamides otherwise inaccessible by semisynthesis and underpins a platform for the discovery of new lincosamide antibiotics.
