摘要:

Measurements of the heat of formation of N2H2from the appearance potential form/e30 ions from N2H4give irreproducible results. Using N2H2, reproducible values for the appearance potentials ofm/e30, 29, and 28 ions were obtained. These values yield an ionization potential of N2H2, IP(N2H2) = 9.7 ± 0.1 V, a heat of formation of N2H2, ΔHf(N2H2) = 36 ± 2 kcal/mol and a proton affinity of N2, PA(N2) = 5.6 eV. An estimate of the ionization potential of N2H radical, IP(N2H) = 7.6 V, was also obtained.

ISSN:0008-4042    

DOI:10.1139/v76-001

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Germanium atoms in all the three spin orbit states arising from the 4p2ground state configuration, 43P0, 43P1(557 cm−1), and 43P2(1410 cm−1), have been generated by the pulsed irradiation of GeBr4and monitored photoelectrically in absorption by time-resolved attenuation of atomic resonance radiation derived from a microwave discharge. The decays have been monitored in the presence of added gases and absolute second order rate constants for the removal of all three atomic states reported for the collision partners, He, Xe, O2, CO, NO, and GeBr4. These rate constants constitute the first detailed rate data for germanium atoms in any specific quantum state.

ISSN:0008-4042    

DOI:10.1139/v76-002

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

In non-associated dilute aqueous electrolyte solutions, the deviation from ideality is principally attributed to the interionic interactions and hydration of ions. Stokes and Robinson combined Bjerrum's thermodynamic treatment of ion–solvent interactions with Debye–Hückel treatment of interionic interactions to obtain a two-parameter equation. In very dilute regions, the Stokes and Robinson's equation reduces to a much simpler form,i.e.Activity coefficients of an electrolyte at lower concentrations, say up to 0.1 m, can be calculated from the equation provided suitable values of &([a-z]+); andhare available. Solutions of hydrogen chloride and sodium chloride were chosen as examples. The results agree with the existing data very satisfactorily.

ISSN:0008-4042    

DOI:10.1139/v76-003

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

In strong acids, such as FSO3H and 96% H2SO4, bicyclo[3.2.0]heptan-6-one and bicyclo[3.2.0]hept-2-en-7-one undergo a clean isomerization to form protonated cyclohept-2-enone and cyclohepta-2,4-dienone, respectively. Substituted derivatives undergo comparable ring expansions when dissolved in these strong acids. The seven-membered ring ketones can be recovered on quenching the acid solutions with a NaHCO3–ether mixture. In contrast, bicyclo[3.2.0]hept-2-en-6-one when dissolved in FSO3H rearranged to give protonated 1-acetylcyclopentadiene. The mechanism and synthetic utility of these reactions is discussed.

ISSN:0008-4042    

DOI:10.1139/v76-004

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

The equilibrium constant for the extraction of thiocyanic acid by methylisobutyl ketone at constant ionic strength, depends on the nature of alkaline cations present in the aqueous phase. The phenomenon could be explained by the existence of ion pairs for which the association constantKpis derivable. However the extraction of chlorpromazinium thiocyanate by the same solvent and the formation of the monothiocyanate complex of zirconium in aqueous phase are both independent of the nature of the electrolyte. The observed variations for the extraction of thiocyanic acid which exist also for the extraction of hydrochloric and perchloric acids by methylisobutyl ketone, result from the variation of species activities with a change in the identity of the cations.

ISSN:0008-4042    

DOI:10.1139/v76-005

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Organo-tin catalysts have been used to prepare a large number of new carbamates of tertiary alcohols. Cyclization of carbamates of unsaturated tertiary alcohols leads to the formation of 2-oxazolidinones, and provides a new synthetic route for some of these compounds.

ISSN:0008-4042    

DOI:10.1139/v76-006

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

The infrared spectra of diluted solutions of acetone, acetone-d6, cyclopentanone, cyclopentanone-d4, and cyclohexanone have been measured in the C=O stretching region from 290 to 90 K. As the solutions are cooled, several new bands appear at lower and lower frequencies. An interpretation of these spectra is given in terms of molecular association and anharmonic resonances.

ISSN:0008-4042    

DOI:10.1139/v76-007

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

5H-Oxazolo[4,5-b]phenoxazine (5) was synthesized by the reaction of 3-amino-2-hydroxyphenoxazine hydrochloride (2) with formamide. A series of styryl-oxazolophenoxazines (9) were prepared by condensation of 2-methyl-5-acetyloxazolo[4,5-b]phenoxazine methiodide (8) with aromatic aldehydes. By contrast, 2-aryl-oxazolophenoxazines (14) were synthesized by reaction of 3-aminophenoxaz-2-one (1) with the appropriate aldehydes in the presence of an acid–base catalyst. The biological activities of some of these compounds were tested.

ISSN:0008-4042    

DOI:10.1139/v76-008

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Four newexo- double pyrazolines3–5have been prepared from norbornadiene and dimethyl phenyldiazomethylphosphonate; their structures have been proven by nmr spectroscopy. There is a strong predominance of the isomers with the two aryl groupssynto the bridge. When the two aryl groups were different no electronic interaction between them could be detected by uv spectroscopy. Direct photolysis of the double pyrazolines leads to the corresponding double cyclopropanes with retention of configuration.

ISSN:0008-4042    

DOI:10.1139/v76-009

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

The crystal and molecular structure oftrans-dichloro(bis(isopropyl)sulfoxide-S)(1-methylcytosine-N)platinum(II) has been determined by single crystal X-ray diffraction. The crystals are triclinic witha = 16.205(5),b = 8.078(2),c = 6.776(2) Å, α = 106.53(2), β = 96.35(2), γ = 98.54(2)°. The space group isand there are two molecules per unit cell. A total of 2294 independent reflections, of which 2023 were observed, were examined on a Syntexdiffractometer. The structure was refined by full matrix least squares analysis to anR2value of 0.0427. The ligands form a rough square around the platinum atom with Pt—Cl(1), 2.304(3), Pt—Cl(2), 2.287(4), Pt—S, 2.232(2), Pt—N, 2.058(7). Distances within the ligands are normal. The plane of the cytosine ring is at 84.4° to the plane formed by the ligands around platinum.

ISSN:0008-4042    

DOI:10.1139/v76-010

出版商:NRC Research Press    

年代:1976

数据来源: NRC