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Tricyanomethyl

First examine the geometry of methyl radical. Is it planar or puckered Examine the geometries of 2-methy 1-2-propyl radical, trifluoromethyl radical, trichloromethyl radical and tricyanomethyl radical. Classify each of the substituents (methyl, fluoro, chloro and cyano) as a n-electron donor or as a Tt-electron acceptor (relative to hydrogen). Does replacement of the hydrogens by 7t-donor groups make the radical center more or less puckered Does replacement by Jt-acceptor groups make the radical center more or less puckered Justify your observations. [Pg.236]

Onto which atoms (carbon, nitrogen or both) is the unpaired electron in tricyanomethyl radical delocalized Rationalize your result by drawing resonance contributors. [Pg.236]

The above book [1] deals, in 26 chapters in 5 sections, with theoretical and practical aspects of the use and safe handling of powerful oxidants and their complementary reactive fuels. Materials include nitrogen pentaoxide, perfluoroam-monium ion and salts, nitronium tetrafluoroborate, hydrazinium mono- and diperchlorates, nitronium perchlorate, tricyanomethyl compounds, difluoramine and its alkyl derivatives, oxygen difluoride, chlorine trifluoride, dinitrogen tetraoxide, bromine trifluoride nitrogen fluorides, and liquid ozone-fluorine system. [Pg.360]

Synthesis and Thermochemistry of Tricyanomethyl and Other Polycyano Compounds... [Pg.114]

A series of tricyanomethyl compounds were prepared in refluxing acetonitrile hy alkylating potassium tricyanometha-nide with alkyl iodides, allyl, propargyl, and benzyl bromides. Yields of 20-57% were obtained for mono- and difunctional halides with a reflux time of 72 hours. The heats of combustion of these tricyanomethyl compounds as well as of two polycyano compounds were measured using a Dickenson-type calorimeter, and heats of formation were calculated with a precision of approximately 1.0%. From Pitzers values for C—C and C—H bond energies, that of the tricyanomethyl moiety is calculated to be about 810 kcal./mole, and the tricyanomethyl group is less stable than expected from comparison with AH°f of propylcyanide. [Pg.114]

The tricyanomethyl compounds are a stable class of organic compounds whose solid products can be purified by sublimation. Their exceptional thermal stability is evidenced by the fact that 1,1,1,6,6,6-hexa-cyanobutyne-3 was sublimed at 170° C./0.05 mm. The infrared spectra of these compounds show a weak absorption for cyano at 4.4 /a. The properties of these compounds are summarized in Table I. [Pg.115]

In addition to the above tricyanomethyl compounds, 1,4-dicyano-butyne-2 (8) and 1,1,2,2-tetracyanocyclopropane (22) were prepared for the thermochemical studies. [Pg.115]

It is also possible to calculate the bond energy of the tricyanomethyl moiety in each of the molecules. To do this we calculate standard heats of formation at 0° K. from the values given in Table III for 298° C. In the absence of reliable data we note the following reported (13) specific heats, Cp ... [Pg.121]

These are also original results which could explain the low decay rate constant of the tricyanomethyl radical. [Pg.75]

CONH2 and COOMe, is discussed on p. 214. Isocyanatomethyl, Fe—CH2NCO and alkoxycarbonyl, Fe—COOR derivatives have also been prepared [55 ]. The tricyanomethyl complex, r-C5H5Fe(CO)2C(CN)3 has been prepared from 7r-C5H5Fe(CO)2Cl using Ag+[C(CN)3] [50]. [Pg.234]


See other pages where Tricyanomethyl is mentioned: [Pg.308]    [Pg.114]    [Pg.115]    [Pg.117]    [Pg.122]    [Pg.116]    [Pg.65]    [Pg.72]   
See also in sourсe #XX -- [ Pg.242 ]

See also in sourсe #XX -- [ Pg.108 ]




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