摘要:

Reinvestigation of the acetolysis of 5,5-diphenylcyclononyl tosylate (1) has confirmed the absence of any transannular processes and deamination of the corresponding amine16gave a similar resuit. Trifluoroacetolysis of1caused extensive transannular hydride migration but no phenyl migration. The former may be due to secondary acid-catalyzed rearrangements.

ISSN:0008-4042    

DOI:10.1139/v71-541

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Acrylamide andN-vinyl pyrrolidone were copolymerized at 60° in binary aqueous solutions containing 0, 5, 67, and 80% glycerol by weight. A marked increase in the reactivity of acrylamide relative to that ofN-vinyl pyrrolidone was observed. This increase is interpreted in terms of the relative reactivity of monomer and polymeric radical in the reaction medium.

ISSN:0008-4042    

DOI:10.1139/v71-542

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The chloride bridged complex, [Pt2Cl2(PEt3)4][BF4]2,reacts with C2F4and H2O or with aldehydes to yieldtrans-[PtCl(CO)(PEt3)2][BF4] and with HCOOH to cause catalytic decomposition of the acid to CO2and H2. These reactions are of interest in mechanistic comparisons with other d8complexes. Similar reactions of related platinum and palladium complexes are also described, together with the synthesis of the new complexes, [Pd2X2(PR3)4][BF4]2, where X = Br or I for R = phenyl and X = Br for R = ethyl, cw-[MCl(PEt3)2(Py)][BF4]and [MCl(PPh3)3][BF4] where M = Pd or Pt.

ISSN:0008-4042    

DOI:10.1139/v71-543

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Structure analysis of (−) scopolamineN-oxide (1) hydrobromide monohydrate by X-ray crystallography has proven that theN-methyl group is axial and the amineoxide function is equatorial. The absolute configuration of the tropic acid residue has also been determined by anomalous scattering as beingS, in complete agreement with chemical correlation experiments.TheN-stereoisomer of1has also been detected as a minor product2for the first time, as a result of using 100 MHz n.m.r. spectroscopy in the product analysis of the oxidation of (−) scopolamine with hydrogen peroxide in ethanol. A similar n.m.r. study was undertaken with atropine and tropine and correlation of chemical shifts withN-configuration in theN-oxides,3–6, was attempted.N-oxidation of scopolamine, and by analogy of related tropane bases, has taken a preferentially equatorial course, similar to other quaternization reactions.

ISSN:0008-4042    

DOI:10.1139/v71-544

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Using both infrared and laser Raman techniques the low temperature vibrational spectra of KBH4, KBD4, NaBH4, and NaBD4have been recorded. The spectra of the external lattice vibrations are consistent with the following borohydride ion site symmetries:Tdfor potassium borohydride andD2dfor sodium borohydride. Translational frequencies are assigned and librational frequencies are inferred from absorptions tentatively assigned as second overtones. Comparison of the low and high temperature vibrational spectra suggests the following disorder–order phase changes:Oh5 → Td2for potassium borohydride andOh5 → D2d9for sodium borohydride.

ISSN:0008-4042    

DOI:10.1139/v71-545

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The infrared spectra of polycrystalline LiBH4and LiBD4have been recorded in the region 4000–50 cm−1at 80 °K. Raman spectra of polycrystalline samples were also recorded at this temperature. The spectra of theandlattice vibrations are consistent with symmetrically equivalent borohydride ions which lie on either general positions, two-fold axes or mirror-planes. Six lattice vibrations of translatory origin appear in the infrared spectrum of LiBH4and a mode of libratory origin is inferred from an absorption tentatively assigned as a second overtone of a librational mode. Similar spectral results are obtained for LiBD4. The inferred librational frequencies are 418 cm–1for theions and 319 cm–1for theions.

ISSN:0008-4042    

DOI:10.1139/v71-546

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The γ-radiolysis of low concentrations of neopentane in liquid cyclo-C5H10and C2H6at 0.25 g ml−1density leads to methane yields much greater than expected from the mixture compositions. In cyclo-C6H12,n-C6H14, cyclo-C6H11CH3, and 3-methylpentane the yields are much less than expected. The effect is explained in terms of positive ion scavenging which is enhanced by added electron scavengers. The efficiency of scavenging by C(CD3)4in C2H6is equal to that of ND3. The efficiency in cyclo-C5H10is less than that in C2H6but is greater than that observed previously in this solvent.

ISSN:0008-4042    

DOI:10.1139/v71-547

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

Monosaccharides with acis-configuration at C-2 and -3 readily undergo inversion at C-2 in an acetolysis medium composed of acetic acid, acetic anhydride, and sulfuric acid. The acetolysis-inversion reaction has been carried out with 2,3;5,6-di-O-isopropylidene-D-gulofuranose, 2,3;6,7-di-O-isopropylidene-D-glycero-D-gulo-heptose, 2,3-O-isopropylidene-D-ribose,D-ribose, andD-mannose using chromatography for isolation of the deacetylated epimeric products. The reaction requires a medium with a high concentration of acetic acid (ca. 90%) and appears to take place only with furanose structures. Inversions observed with the unsubstituted pyranosesD-ribose andD-mannose probably occur because of tautomerization to furanose forms. The epimerization proceeds in the direction which yields a smaller number ofcis-oriented groups at C-2, -3, and -4 of the furanose forms of monosaccharides.

ISSN:0008-4042    

DOI:10.1139/v71-548

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

5-Unsubstituted 1,2-dithiole-3-thiones undergo addition reactions with dimethyl acetylenedicarboxyl-ate and dibenzoylacetylene to give amorphous 2-thioformylmethylene-1,3-dithioles. In certain cases these may undergo further addition of activated acetylene to give thiopyranspiro-1,3-dithioles, but may also lose sulfur to give bis-1,3-dithiolylidene-2-butenes, which are probably formed via initial dimerization of the thioformylmethylenedithioles. The stereochemistry of the products is discussed briefly.

ISSN:0008-4042    

DOI:10.1139/v71-549

出版商:NRC Research Press    

年代:1971

数据来源: NRC

摘要:

The chemical properties and n.m.r. data of the two isomers of 1-(4-chlorophenyl)-2,3-dimethyliso-indoline are reported. The crystal structure of one of the isomers was determined by X-ray diffraction.

ISSN:0008-4042    

DOI:10.1139/v71-550

出版商:NRC Research Press    

年代:1971

数据来源: NRC