摘要:

The acylation of 1-methylcyclohexene with propionyl, butyryl, and benzoyl chloride in the presence of different Lewis acids is reported. Theexoandendo1-acyl-6-methyl bicyclo [3.1.0]hexane isomers are formed with variable percentages depending upon the catalyst used. An unexpected compound, 3-benzoyl-2-methylcyclohexanol, was isolated from the reaction of 1-methylcyclohexene with benzoyl chloride. The acylation of 1,3,3,5,5-pentamethylcyclohexene with acetyl chloride – stannic chloride gave no bicyclic compounds.

ISSN:0008-4042    

DOI:10.1139/v71-294

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

At room temperature 1,4-diphenyl-1,2,3-triazolyllithium rapidly undergoes fragmentation to nitrogen and lithium (N-phenyl)phenylketenimine anion8c,. Some of the reactions of this ambident anion have been studied. Reaction of8cwith methyl iodide results inC-methylation to a mixture of (N-phenyl)methylphenylketenimine and 3-methyl-1,3-diphenyl-4-(2′-phenylethylene)-2-phenyliminoazetidine. A six-membered heterocyclic compound, 6-anilino-1,3,5-triphenyluracil, results from the reaction between8cand phenyl isocyanate. With dimethyl sulfate and methyl chloroformateN-alkylation andN-acylation takes place predominantly, formingN-methyl-N-phenyl-2-phenylethynylamine andN-carbomethoxy-N-phenyl-2-phenylethynylamine respectively. Reaction of8cwith methanol and ethanethiol gives an iminoester and an iminothioester respectively.1-Phenyl-1,2,3-triazolyllithium and 4-methyl-1-phenyl-1,2,3-triazolyllithium undergo fragmentation at somewhat higher temperatures.

ISSN:0008-4042    

DOI:10.1139/v71-295

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The p.m.r. spectra of the methyl derivatives of 2-fluoropyridine are analyzed. The signs and magnitudes of the long-range spin–spin coupling constants between the methyl protons and the ring protons and between the methyl protons and fluorine are consistent with a model in which the nitrogen atom polarizes the sigma electron system but leaves the pi electron contribution to the coupling constants relatively unchanged. There are dramatic changes in the ring proton – fluorine couplings while the couplings involving the methyl protons vary little from those in the corresponding toluene derivatives. Thus the coupling over six bonds between fluorine and methyl protons is 1.25 ± 0.03 Hz in 2-fluoro-5-methyl pyridine compared to 1.15 ± 0.02 Hz inp-fluorotoluene.

ISSN:0008-4042    

DOI:10.1139/v71-296

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

A dextrorotatory glucan has been isolated in good yields from the culture medium ofTremella mesentericaNRRL-Y6158. The glucan consumed 1.32 mol of periodate and released 0.33 mol of formic acid per mol anhydroglucose and reduction and hydrolysis of the periodate-oxidized glucan yielded glycerol and erythritol in the ratio 1.0:1.9. Partial hydrolysis of the glucan released maltose, isomaltose, panose, isomaltotriose andO-α-D-glucopyranosyl-(1 → 4)-O-α-D-glucopyranosyl-(1 → 6)-D-glucose. The fully methylated glucan was composed of 2,3,4,6-tetra-O-methyl glucose (0.5%), 2,3,4-tri-O-methyl glucose (31.4%), and 2,3,6-tri-O-methyl glucose (67.6%).These results indicate that the glucan was a linear molecule composed of approximately 200 α-D-glucopyranose units linked 1 → 6 and 1 → 4 in the ratio 2:1. Structurally the glucan resembles to varying extents the neutral glucans obtained from the yeast-like fungi of thePullulariaspecies.

ISSN:0008-4042    

DOI:10.1139/v71-297

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

An investigation has been made of the relative importance of the possible pathways [2a]–[2d]for the reaction in the gas phase at room temperature between the excited oxygen atom O(1D2) and N2O, using the photolysis of NO2, O3, and N2O as sources of the excited atom. Measurement of the yields of N2and NO from the photolysis at 2288 Å of mixtures of NO2and N2O has led to a value of 1.01 ± 0.06 fork2a/k2b, the ratio of the rate constants for [2a] and [2b], in excellent agreement with the value of 0.99 ± 0.06 obtained from determination of the yields of N2and NO2arising from the flash photolysis of O3–N2O mixtures. The isotopic composition of the N2produced in the photolysis of15NO2–N2O mixtures indicated thatk2c/k2a < 5 × 10 – 3. Furthermore, the value ofk2a/(k2b + k2d) = 1.08 ± 0.19, obtained from a study of the effect of CO2and Xe additions on the yield of N2from the photolysis of N2O at 2288 Å, suggests that deactivation [2d] does not make an important contribution to the total rate constant for destruction of O(1D2).

ISSN:0008-4042    

DOI:10.1139/v71-298

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Spin–spin coupling constants between methylene protons and ring protons over six and five bonds,, are reported for α-substituted derivatives of 2,6-dichlorotoluene. Potential energy calculations suggest that the C—X bond of the CH2X group lies perpendicular to the plane of the ring. The six-bond coupling is dominated by a π electron mechanism and depends on the conformation of CH2X with respect to the aromatic plane and on the electronegativity of the substituent, X. The five-bond coupling is independent of X and it is suggested that the decrease in the π electron contribution to this coupling caused by the increasing electronegativity of X, is compensated by a corresponding increase in the sigma electron contribution.

ISSN:0008-4042    

DOI:10.1139/v71-299

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

We present a theoretical description of an effect that we call three-photon electro-optical rotation. We consider a high-intensity beam of polarized monochromatic light, which interacts with an assembly of identical molecules. We calculate the probability of the absorption of two photons from this beam of light and the simultaneous reemission of a third photon, which has the same direction of propagation as the incident light and a direction of polarization that is perpendicular to the incident light. The energy of the emitted photon is the sum of the energies of the absorbed photons. We found that the effect is observable in the presence of a homogeneous electric fieldF, directed along the direction of polarization of the emitted beam of light. The effect is proportional toFand to the molecular dipole moment and it is inversely proportional to the absolute temperatureT.

ISSN:0008-4042    

DOI:10.1139/v71-300

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Calorimetric enthalpies of mixing have been measured over the whole composition range for the water – ethylene oxide system at 10.75 and 20.00 °C and for the deuterium oxide – ethylene oxide system at 13.45 and 20.00 °C. Less extensive measurements have been made for dilute ethylene oxide solutions in water at 0.6 °C and in deuterium oxide at 4.1 and 7.3 °C. The experimental S-shaped, enthalpy of mixing – composition curves are interpreted in terms of solution hydrogen bonding changes, with particular reference to the hydrogen bonding of water. At low ethylene oxide mole fractions the deuterium oxide systems are more exothermal and at high ethylene oxide mole fractions more endothermal than the corresponding water systems. A good correlation is found between the enthalpy of mixing and the water proton magnetic resonance chemical shift for solutions with greater than 0.55 mol fraction of ethylene oxide.

ISSN:0008-4042    

DOI:10.1139/v71-301

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The products of cycloaddition of silyldiazoalkanes with representative alkenes are described, together with their photolysis products. The photolysis of silyldiazoalkanes yields silylcarbenes which undergo typical reactions.

ISSN:0008-4042    

DOI:10.1139/v71-302

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Dehydrogenation with high potential quinones has been extended to dihydro derivatives of non-aromatic hydrocarbons using 7,12-dihydropleiadenes as models. Reaction of 7-phenyl-7,12-dihydropleiadene with high potential quinones resulted in dehydrogenative cyclization whereas preparative scale and rate studies in 9-aryl-9,10-dihydroanthracenes gave no evidence of aryl participation during quinone dehydrogenation due to geometrical restrictions on this system.

ISSN:0008-4042    

DOI:10.1139/v71-303

出版商:NRC Research Press    

年代:1971

数据来源: NRC