摘要:

From the sap of the sugar maple (AcersaccharumMarsh) two trisaccharides have been isolated by column and paper chromatography. One was identified asO-β-D-fructofuranosyl-(2 → 6)α-D-glucopyranosyl(1 → 2)β-D-fructofuranoside (6G-fructosylsucrose), the other was tentatively established as either 6F-fructosylsucrose or 1F-fructosylsucrose. These trisaccharides are not related in either composition or structure to the polysaccharides present in the sap and wood.

ISSN:0008-4042    

DOI:10.1139/v61-147

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

Raney nickel and hydrazine readily cleave the nitrogen–nitrogen bond of a number of N,N′-diacylated hydrazines to produce the corresponding amides in good yield.

ISSN:0008-4042    

DOI:10.1139/v61-148

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The 'pervanadium complex' is investigated in a general manner. The kinetics of its thermal decomposition in acid solution are shown to be first order with respect to pervanadium, the apparent activation energy is 26.5 ± 1.0 kcal/mole, and possible mechanisms are suggested. The effect of various acids upon the nature of the decomposition products is determined: almost quantitative yields of vanadium (V) or vanadium (IV) are obtained in very dilute or concentrated acid, respectively. Spectrophotometric studies indicate that in acid solution two separate complexes exist: a red (1:1) cationic complex and a yellow (1:2) anionic complex. The stoichiometry of the equilibrium between the two complexes in solutions of sulphuric acid is investigated by a method of 'discrete variations'. The equilibrium could be described bywhereKr/y = 2.2 ± 0.2 at 22 °C. The anion is shown to play an important part in determining the nature of the pervanadium complex.

ISSN:0008-4042    

DOI:10.1139/v61-149

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The infrared spectra of 2,6-dimethyl-4-pyrone in solution, and in complexes with HgCl2, ZnCl2, BF3, SbCl5, and HBr have been recorded. A band at 1639 cm−1in the free pyrone moves to progressively lower frequencies in the complexes as the Lewis acid strength increases, identifying this band as the carbonyl stretching frequency and the donor site as the carbonyl group. A higher-frequency band, at 1678 cm−1in the free pyrone, moves to lower frequency on complex formation, but to a much smaller extent, and is to be identified with a stretching mode of the ring. The site of protonation in 2,6-dimethyl-4-pyrone salts has been unequivocally shown to be the carbonyl oxygen atom.

ISSN:0008-4042    

DOI:10.1139/v61-150

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The separation of several cyclic terpene hydrocarbons and some oxygenated derivatives was studied on a variety of triglyceride and dioleate ester columns. Use of rapeseed oil, partially hydrogenated rapeseed oil, olive oil, triolein, tristearin, methyl oleate, and potassium oleate as liquid phases led to the conclusion that the presence of an esterified mono-unsaturated long-chain acid is a desirable constituent of the liquid phase. Dioleate esters of 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, and polyethylene glycol showed useful differences in the degree of separation of both terpene hydrocarbons and oxygenated derivatives. Ether linkages, as in the di- and poly-ethylene glycol ester, also were associated with favorable separations. When the liquid phase contained free hydroxyl groups, the degree of separation of hydrocarbons and ketones was in general less favorable. The spacing of the ester groups was found to have some effect on retention data. The separation of such critical pairs of isomers as tricyclene and α-pinene, α-fenchene and camphene, and also geometrical isomers of oxygenated derivatives is facilitated by use of several of these liquid phases.

ISSN:0008-4042    

DOI:10.1139/v61-151

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The complete analysis of the neutral volatile oil of the leaves of Eastern white cedar (ThujaoccidentalisL.) by means of gas–liquid chromatography was attempted. The mixture of terpenes was resolved into 28 monoterpenoid components and the major ones were isolated in 5- to 20-mg amounts. Comparison of infrared spectra and retention times with those of authentic specimens led to the positive identification ofd-α-pinene, camphene, sabinene,d-limonene,p-cymene, γ-terpinene,l-fenchone,l-α-thujone,d-isothujone, camphor, and bornyl acetate. α-Thujene, β-pinene, myrcene, 1,8-cineole, terpinolene, and terpinen-4-ol were tentatively identified. The percentage composition of a commercial sample of the oil and of one obtained from a tree grown in Saskatoon was determined. The latter oil contained 7.0 to 7.5% of sesquiterpenoid components, which were resolved into four peaks on polyester columns at 180 °C.

ISSN:0008-4042    

DOI:10.1139/v61-152

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

Previous work on the mechanism of sulphonium salt solvolysis is reviewed briefly. Rate data, determined by two independent methods, is presented for the solvolysis of dimethyl-t-butyl sulphonium iodide, bromide, and chloride in water and various ethanol–water mixtures. Rate dependence on the anion character and concentration of salt is shown to develop as the dielectric constant of the medium is lowered. The results are interpreted in terms of the increasing importance of an ion-pair mechanism as the composition of the medium is changed. The interpretation is substantiated by independent evidence for ion-pair formation.

ISSN:0008-4042    

DOI:10.1139/v61-153

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

The infrared spectra of trimethylamine oxide, its hydrate, and its hydrochloride in the solid state were measured over the range 300 to 3500 cm−1to ascertain the nature of the bonds in these compounds. From the observed stretching frequencies, 937 cm−1for N—O and 945 cm−1for C—N, the corresponding bond lengths are calculated to be 1.44 and 1.50 Å in agreement with X-ray and electron diffraction data. Both these frequencies remain unchanged in the hydrate and the hydrochloride as could be expected for molecular compounds. However, in the hydrochloride most of the evidence points to an ionic constitution. In both the hydrate and the hydrochloride the hydrogen bonds are particularly strong presumably because of the formal charges.

ISSN:0008-4042    

DOI:10.1139/v61-154

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

A method is presented for preparing a reproducible silica glass or quartz surface that does not craze during rate of solution measurements in solutions of the five group I hydroxides. For silica glass, initial rates are a maximum at 8 Mfor at least NaOH and KOH and are an inverse function of ion size for the five cations and tetramethyl ammonium ion. A proposed mechanism of water addition followed by reaction with hydroxyl ion is used to explain the maximum rate and the effect of solution products and the substitution of methanol for water as a solvent. For quartz an explanation is offered for the lower rate and for the absence of a maximum rate below 27 MNaOH. A common temperature coefficient of 20 kcal mole−1is reported for all reactions in water. The crazing of finely ground or polished silica glass surfaces is related to the presence of surface cracks and their enlargement by possible conversion of some silica to quartz in NaOH solution.

ISSN:0008-4042    

DOI:10.1139/v61-155

出版商:NRC Research Press    

年代:1961

数据来源: NRC

摘要:

A study has been made of the decomposition of methanol vapor by Hg 6(3P1) atoms, under static conditions, at 25 °C. A system constructed entirely of quartz was employed to eliminate the dark reaction between methanol vapor and pyrex glass to form trimethyl borate. Emphasis in this investigation was placed on the determination of the nature of the primary processes operative, and to this end, the reaction was studied in some detail in the presence of nitric oxide.For pure methanol, the major primary products were found to be hydrogen and ethylene glycol. The primary quantum yield for hydrogen was 0.46. Minor products of primary origin were formaldehyde (0.01), ethane (0.005), and dimethyl ether (0.006), with the numbers in parentheses showing the primary quantum yields.In the presence of nitric oxide, the major products became methyl nitrite, nitrous oxide, and water. The quantum yield of methyl nitrite rose steadily with increasing NO concentrations. For a 1:1 CH3OH:NO mixture, the primary quantum yield for methyl nitrite was found to be 0.56. The behavior of the reaction in the presence of NO establishes fairly unequivocally that the major primary process involves O—H bond scission to form methoxy radicals and H atoms. These primary radicals then form hydroxymethyl radicals by abstraction reactions with the substrate. The ethylene glycol product arises by recombination of the secondary hydroxymethyl radicals. These conclusions were further substantiated by mass spectrometric analysis of the products of the decomposition of CD3OH. It was shown that CD3OD is a significant product of the reaction.

ISSN:0008-4042    

DOI:10.1139/v61-156

出版商:NRC Research Press    

年代:1961

数据来源: NRC