摘要:

The decomposition of benzoyl hypochlorite, the intermediate in the Hunsdiecker reaction between chlorine and silver benzoate, is accelerated by light and by azobisisobutyronitrile (AIBN), but not by transition metal ions. The molar yield of the chlorobenzene produced in the decomposition increases as the temperature of the reaction mixture is raised, but is independent of whether or not the reaction is promoted by light or AIBN. It is suggested that this variation in the yield is a result of the readier decarboxylation at higher temperatures of the benzoyloxy radicals which are believed to be intermediates in the decomposition process. No such pronounced effect of temperature on the yield of halides from aliphatic silver carboxylates has been observed, presumably because aliphatic acyloxy radicals decarboxylate readily even at low temperatures.

ISSN:0008-4042    

DOI:10.1139/v71-139

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The reactions of CH3radicals with methyl formate and CD3radicals with methyl formate and methyl formate-dhave been studied. The CH3and CD3radicals were produced by the photolysis of acetone and acetone-d. The Arrhenius parameters (logA,Ain 1 mol−1 s−1;E, in kcal mol−1) for hydrogen abstraction are as follows

ISSN:0008-4042    

DOI:10.1139/v71-140

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

An investigation has been made of the influence of pHon the kinetics of hydration of tricalcium silicate in a large excess of water. The rate constants increase with increasing hydrogen ion activityin the liquid phase when theis low; however, as theis increased further the rate constants become independent of theThe results have been interpreted by proposing that the rate constants are proportional to the hydrogen ion activity adsorbed,on the solid surface. The Langmuir adsorption isotherm was used to correlate the hydrogen ion activity on the surface to the hydrogen ion activity in the liquid phase.Several particle sizes of tricalcium silicate were investigated and a surface area effect is indicated.

ISSN:0008-4042    

DOI:10.1139/v71-141

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

A study has been made of the infrared O—H bands for CH3OH, DOH, and H2O in solution and of their correlation with hydrogen bonding and solvent basicity. Infrared bands for the three fundamentals and the first bending overtone of H2O and for the O—H stretching fundamentals of DOH and CH3OH have been measured between 30 and −40 °C in a solvent range extending from weakly interacting fluorocarbons to strongly hydrogen-bonding organic amines. The O—H stretching bands for the weakly acidic solutes CH3OH, DOH, and H2O are mostly Lorentzian in shape and move to lower frequencies with higher extinctions in the more basic solvents. Many correlations are found between the stretching frequencies and band areas, and between the frequencies and solvent basicity. Monofunctional CH3OH is found to be a stronger acid and forms stronger hydrogen-bonds with a given base than do the doubly bonded DOH and HOH which show equal dibasic acid strengths.The wide, overlapped, fundamental stretching bands for H2O strongly hydrogen-bonded to the tertiary amines and for ice have been partially resolved and unequivocally assigned, showing that there is no cross-over of the ν3and ν1bands despite the strong hydrogen-bonding.At higher temperatures in solvents containing both hydrophobic and strongly basic groups water was found with the lowerCstype symmetry, in which unbonded O—H groups gave sharp bands in the 3680–3650 cm−1region in addition to the wide hydrogen-bonded bands at lower frequencies.

ISSN:0008-4042    

DOI:10.1139/v71-142

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

A simple six-step synthesis, from homoveratrylamine, of 5,6-dimethoxy-2,3,7,8,9,9a-hexahydro-1-(p-toluenesulfonyl)-1H-benzo[d,e-1,7]naphthyridine, the first representative of a novel heterocyclic ring system, is described. Various transformation products and derivatives of the ring-system are also recorded.

ISSN:0008-4042    

DOI:10.1139/v71-143

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

When 4a-ethyl-2,3,4,4a-tetrahydrocarbazole or its 4a-bromoethyl analog reacted with ozone, only a small amount of material that corresponded to the anticipated ozonolysis product was obtained, the principal reaction pathway leading to a 4a-substituted 1-acetoxytetrahydrocarbazolenine, the product of an oxidative rearrangement.

ISSN:0008-4042    

DOI:10.1139/v71-144

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The effect of several oxidizing metal salts on the square planar iridium(I) complexestrans-[IrI(CO)-(PPh3)2X] (where X− = Cl−, Br−, I−, N3−, NCO−, NCS−, and NO2−) has been investigated. With nitrate salts of Ce(IV), Fe(III), and Cu(II), several of the reactions gave products characterized by analysis and i.r. spectroscopy as [IrIII(CO)(PPh3)2X(NO3)2]. With CuCl2•2H2O and CuBr2several of the same starting materials gave products, [IrIII(CO)(PPh3)2XY2] (where X− = NCO−, NCS−, NO2−and Y− = Cl−; and X− = NCO−, NCS−, Br−, NO2−and Y− = Br−). These have been similarly characterized. An iridium(III) complex, [IrIII(PPh3)2(NO3)2H] has also been characterized.

ISSN:0008-4042    

DOI:10.1139/v71-145

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Pyrolysis and photolysis of 3,4,5-triphenyl-4-phosphabicyclo[3.1.0]hex-2-ene-4-oxide and the 1:1 adduct of diazomethane with 1,2,5-triphenylphosphole oxide lead to the formation of compounds of formula C46H36O2P2, andC46H34O2P2, respectively. These compounds are shown to be derivatives of the 4,4′-diphosphabi(cyclohexa-1,5-dienyl) and 4,4′-diphosphabi(cyclohexa-2,5-dienylidene) systems, respectively, and possible mechanisms for the formation of these systems are briefly discussed.

ISSN:0008-4042    

DOI:10.1139/v71-146

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Alkaline hydrolysis of 1-iodomethyl-1,2,5-triphenylphospholium iodide gives 3,4,5-triphenyl-4-phosphabicyclo[3.1.0]hex-2-ene-4-oxide in very high yield. Three possible mechanisms are discussed and isolation of a key intermediate allows one of these mechanisms to be discarded. Alkaline hydrolysis of 1-allyl-1,2,5-triphenylphospholium bromide in methanol gives 1,2,5-triphenylphosphole and small quantities of a compound C26H27O2P which is an adduct of the original phospholium ion, hydroxide ion, and methanol.

ISSN:0008-4042    

DOI:10.1139/v71-147

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The reaction of norbornene (1) with bromine has been re-investigated and found to give in addition to bromonortricyclene (2) and 2-exo-bromonorbornane (20) a complex mixture of dibromides of which five (15–19) have been isolated and identified. These dibromides have been found to be kinetically controlled products of ionic addition. Apparently dibromide15is also formed to some extent in carbon tetrachloride by a radical mechanism. The product composition from the bromine addition has been compared with that of the analogous chlorination and bromofluorination reactions. Degradation of the 2-exo,3-endo-dibromonorbornane from bromination of 5,6-14C-norbornene has shown that this dibromide is formed by two ionic routes: (a) from a bromonium ion14(or its equivalent), and (b) from the cation12formed by 6,1-hydride shift. Improvements have been made in the first and final steps of the standard norbornene degradation method.

ISSN:0008-4042    

DOI:10.1139/v71-148

出版商:NRC Research Press    

年代:1971

数据来源: NRC