Gas-Phase Flash Reactions of Diborane, Triborane Carbonyl and Tetraborane with Alkynes

1999 ◽  
Vol 64 (5) ◽  
pp. 806-818 ◽  
Author(s):  
Mark A. Fox ◽  
Robert Greatrex ◽  
Norman N. Greenwood ◽  
Martin Kirk
Keyword(s):  
Gas Phase ◽  
High Energy ◽  
Thermally Stable ◽  
Alkyl Derivatives ◽  
Methyl Derivatives ◽  
Derivatives Of

Several known volatile closo-carboranes (1,5-C2B3H5, 1,6-C2B4H6, 2,4-C2B5H7, 1,10-C2B8H10) and their alkyl derivatives and ten new alkyl derivatives of these carboranes were identified from the thermal gas-phase flash reactions of B2H6, B3H7CO and B4H10 with ethyne, propyne and but-2-yne. In addition, nido-C4B2H6 and its methyl derivatives were obtained from B2H6-alkyne flash reactions. All carboranes found in these high-energy reactions are the most thermally stable isomers of their class. The non-isolable borane {B3H7} is suggested as the initiator in all thermal flash reactions reported here.

scholarly journals Electrostatic effects on disproportionation equilibria: dihalogeno and methyl derivatives of benzene

1984 ◽  
Vol 62 (11) ◽  
pp. 2337-2339 ◽  
Author(s):  
Zdeněk Friedl
Keyword(s):  
Gas Phase ◽  
The Other ◽  
Transfer Reactions ◽  
Electrostatic Energy ◽  
Benzene Derivatives ◽  
Strong Resonance ◽  
Conformational Equilibria ◽  
Proton Transfer Reactions ◽  
Methyl Derivatives ◽  
Derivatives Of

The disproportionation equilibria of benzene derivatives X—Ph—Y (X, Y = F, Cl, CH3) in the gas phase, were calculated from their enthalpies and entropies of formation at 298 K. Calculations of the electrostatic energy based on the point charges approximation method predict reasonably well the reaction enthalpies of all meta-benzene derivatives and predict nearly as well the other fluoro- and methyl-derivatives. The theory fails if strong resonance and/or steric interactions are present. The generally better ability of the electrostatic theory to treat disproportionation or conformational equilibria than the proton transfer reactions is also discussed.

Physical Properties of TCNQ Salts with N-Methyl Derivatives of Pyridine

1982 ◽  
Vol 85 (1) ◽  
pp. 257-263 ◽  
Author(s):  
A. Graja ◽  
M. Przybylski ◽  
B. Butka ◽  
R. Swietlik
Keyword(s):  
Physical Properties ◽  
Methyl Derivatives ◽  
Derivatives Of

Methyl derivatives of furan

1974 ◽  
Vol 39 (11) ◽  
pp. 3109-3116 ◽  
Author(s):  
J. Šrogl ◽  
M. Janda ◽  
I. Stibor ◽  
V. Skála ◽  
P. Trška ◽  
...  
Keyword(s):  
Methyl Derivatives ◽  
Derivatives Of

7-O-Alkyl derivatives of daunomycinone

1984 ◽  
Vol 49 (1) ◽  
pp. 313-319 ◽  
Author(s):  
Věra Přikrylová ◽  
Petr Sedmera ◽  
Josef V. Jizba ◽  
Jindřich Vokoun ◽  
Helena Lipavská ◽  
...  
Keyword(s):  
H Nmr ◽  
Toluenesulfonic Acid ◽  
Alkyl Derivatives ◽  
Derivatives Of

Reaction of daunomycinone (I) with alcohols and p-toluenesulfonic acid produces a mixture (~3 : 1) of its (7S)- and (7R)-O-alkyl derivatives II-IX. According to the 1H NMR evidence, the alicyclic ring exists in the 9H8 conformation in (7R)-O-alkyl derivatives, on the contrary to (7S)-epimers and 7-epi-daunomycinone that adopt the 8H9 conformation.

Polarized fluorescense of alkyl derivatives of fluorescein, MitoFluo and C8-Fl, in solutions with liposomes

2020 ◽  
Author(s):  
D.M. Beltukova ◽  
V.P. Belik ◽  
Y.N. Antonenko ◽  
A.A. Bogdanov ◽  
G.A. Korshunova ◽  
...  
Keyword(s):  
Alkyl Derivatives ◽  
Derivatives Of

O'-Methyl derivatives of arabinosylcytosine

1972 ◽  
Vol 46 (4) ◽  
pp. 1734-1741 ◽  
Author(s):  
E. Darżynkiewicz ◽  
J.T. Kuśmierek ◽  
D. Shugar
Keyword(s):  
Methyl Derivatives ◽  
Derivatives Of

Synthesis and reactivity of halide, hydride, and alkyl derivatives of (pentamethylcyclopentadienyl)(bisphosphine)iron(II)

1990 ◽  
Vol 9 (1) ◽  
pp. 260-265 ◽  
Author(s):  
Rocco A. Paciello ◽  
Juan M. Manriquez ◽  
John E. Bercaw
Keyword(s):  
Alkyl Derivatives ◽  
Derivatives Of
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