Base-Catalysed Prototropic Isomerization IV. Isomerization of Conjugated Diynes on a Basic Catalyst. The Mechanism of the Base-Catalysed Isomerization of Triple-Bonds.

AbstractIn this study, based on density functional theory, we propose a new branch of pseudo-fullerenes which contain triple bonds with sp hybridization. We call these new nanostructures fullerynes, according to IUPAC. We present four samples with the chemical formula of C4nHn, and the structures derived from fulleranes. We compare the structural and electronic properties of these structures with those of two common fullerenes and fulleranes systems. The calculated electron affinities of the sampled fullerynes are negative, and much smaller than those of fullerenes, so they should be chemically more stable than fullerenes. Although fulleranes also exhibit higher chemical stability than fullerynes, but pentagon or hexagon of the fullerane structures cannot pass ions and molecules. Applications of fullerynes can be included in the storage of ions and gases at the nanoscale. On the other hand, they can also be used as cathode/anode electrodes in lithium-ion batteries.

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Reactions of coordinated molecules. 40. Addition of a platinum-hydrogen bond across metal acetylide carbon-carbon triple bonds: a direct route to dinuclear .mu.-vinylidene complexes

Journal of the American Chemical Society ◽

10.1021/ja00322a060 ◽

1984 ◽

Vol 106 (10) ◽

pp. 3050-3052 ◽

Cited By ~ 23

Author(s):

Dawood Afzal ◽

P. Galen Lenhert ◽

C. M. Lukehart

Keyword(s):

Hydrogen Bond ◽

Triple Bonds ◽

Vinylidene Complexes ◽

Direct Route

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First total synthesis of the (±)-2-methoxy-6-heptadecynoic acid and related 2-methoxylated analogs as effective inhibitors of the Leishmania topoisomerase IB enzyme

Pure and Applied Chemistry ◽

10.1351/pac-con-11-10-21 ◽

2012 ◽

Vol 84 (9) ◽

pp. 1867-1875 ◽

Cited By ~ 7

Author(s):

Néstor M. Carballeira ◽

Michelle Cartagena ◽

Fengyu Li ◽

Zhongfang Chen ◽

Christopher F. Prada ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Total Synthesis ◽

Leishmania Donovani ◽

Dna Topoisomerase ◽

Triple Bonds ◽

Weak Intermolecular Interactions ◽

Topoisomerase Ib ◽

Effective Inhibition ◽

Acetylenic Fatty Acid

The fatty acids (±)-2-methoxy-6Z-heptadecenoic acid, (±)-2-methoxy-6-hepta-decynoic acid, and (±)-2-methoxyheptadecanoic acid were synthesized and their inhibitory activity against the Leishmania DNA topoisomerase IB enzyme (LdTopIB) determined. Both 2-OMe-17:1 fatty acids were synthesized from 4-bromo-1-pentanol, the olefinic fatty acid in 10 steps and in 7 % overall yield, while the acetylenic fatty acid in 7 steps and in 14 % overall yield. The 2-OMe-17:0 acid was prepared in 6 steps and in 42 % yield from 1-hexa-decanol. The 2-OMe-17:1 acids inhibited LdTopIB, with the acetylenic acid displaying an EC50 = 16.6 ± 1.1 μM, but the 2-OMe-17:0 acid did not inhibit LdTopIB. The (±)-2-methoxy-6Z-heptadecenoic acid preferentially inhibited LdTopIB over the human TopIB enzyme. Unsaturation seems to be a prerequisite for effective inhibition, rationalized in terms of weak intermolecular interactions between the active site of LdTopIB and either the double or triple bonds of the fatty acids. Toxicity toward Leishmania donovani promastigotes was also investigated, resulting in the order acetylenic > olefinic > saturated with the (±)-2-methoxy-6-heptadecynoic acid displaying an EC50 = 74.0 ± 17.1 μM. Our results indicate that α-methoxylation decreases the toxicity of C17:1 fatty acids toward L. donovani promastigotes, but improves their selectivity index.

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Molecular orbital and spectroscopic studies of triple bonds between transition-metal atoms. 2. The d5-d5 Re2Cl4(PR3)4 compounds

Journal of the American Chemical Society ◽

10.1021/ja00347a015 ◽

1983 ◽

Vol 105 (9) ◽

pp. 2606-2611 ◽

Cited By ~ 21

Author(s):

Bruce E. Bursten ◽

F. Albert Cotton ◽

Phillip E. Fanwick ◽

George G. Stanley ◽

Richard A. Walton

Keyword(s):

Transition Metal ◽

Molecular Orbital ◽

Spectroscopic Studies ◽

Triple Bonds ◽

Metal Atoms ◽

Transition Metal Atoms

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Intramolecular Michael and Anti-Michael Additions to Carbon-Carbon Triple Bonds

Synlett ◽

10.1055/s-1993-22461 ◽

1993 ◽

Vol 1993 (06) ◽

pp. 369-374 ◽

Cited By ~ 13

Author(s):

Wolf-Dieter Rudorf ◽

Ralf Schwarz

Keyword(s):

Michael Additions ◽

Triple Bonds

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The reactions of linear conjugated diynes with Dicarbonyl(η-cyclopentadienyl)- cobalt and -rhodium

Australian Journal of Chemistry ◽

10.1071/ch9750285 ◽

1975 ◽

Vol 28 (2) ◽

pp. 285 ◽

Cited By ~ 13

Author(s):

RS Dickson ◽

LJ Michel

Keyword(s):

Thermal Degradation ◽

Aromatic Compound ◽

Substituted Benzenes ◽

Polycyclic Aromatic Compound ◽

Organic Products ◽

Polycyclic Aromatic ◽

Alkyne Complexes ◽

Conjugated Diynes

The reactions of (η-C5H5)Co(CO)2 with the diynes hexa-2,4-diyne and 1,4- diphenylbutadiyne give three isomers of the cyclopentadienone complexes (C5H5)Co[(RC2C2R)2CO], R = Me or Ph, and two isomers of the tris-alkyne complexes (C5H5)2Co2(RC2C2R)3CO, R = Me or Ph. Organic products of formula (RC2C2R)3, R = Me or Ph, (MeC2C2Me)5, and (PhC2C2Ph)3CO have been isolated also. Two isomers of (RC2C2R), were separated and were identified as the 1,2,4-(R)3-3,5,6-(C2R)3- and the 1,3,5-(R)3-2,4,6-(C2R)3-benzenes. The compound (PhC2C2Ph)3CO is believed to be tris(phenylethynly)triphenylcycloheptatrienone, and (MeC2C2Me)5 is probably a polycyclic aromatic compound. Thermal degradation of the complexes (C5H5)2CO2(RC2C2R)3CO gives the substituted benzenes (RC2C2R)3. �� The reaction of (η-C5H5)Rh(CO)2 and hexa-2,4-diyne gives the cyclopentadienone complex(C5H5)Rh[(MeC2C2Me)2CO] and the cycloheptatrienone complex (C5H5)Rh[(MeC2C2Me)3CO].Two isomers of the substituted benzene (MeC2C2Me)3 were obtained also.

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