摘要:

TheE- andZ-isomers of an iodo-Tamoxifen1(1-(p-(β-dimethylaminoethoxy)phenyl)-2-(p-iodophenyl)-1-phenyl-1-butenes) have been prepared from the correspondingE- andZ-amino-Tamoxifens2(2-(p-aminophenyl)-1-(p-(β-dimethylaminoethoxy)phenyl)-1-phenyl-1-butenes) and the molecular structures have been determined from three dimensional X-ray data. Crystals ofE-1are triclinic, space group, withZ = 2 in a cell of dimensionsa = 10.714(2),b = 14.125(3),c = 8.240(2) Å, α = 95.78(1), β = 92.91(1), and γ = 71.41(1)°; those ofZ-1are monoclinic, space groupP21/n, withZ = 4 and cell dimensionsa = 12.675(2),b = 19.553(3),c = 9.483(1) Å, and β = 92.22(1)°. Intensity data collected on an automated four circle diffractometer were used for full-matrix least-squares refinement onF, which converged forE-1atR = 0.054, 2736 observations, and forZ-1atR = 0.042, 3644 observations. The solution of these structures determines the configuration of these isomers as well as the respective amino precursors and allows an unambiguous assignment of the proton nmr spectra of1,2and the Tamoxifens.

ISSN:0008-4042    

DOI:10.1139/v83-075

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

Crystal structures of 2,2,6,6-tetramethyl-4,4-diphenyl-1,4-azaphosphorinanium perchlorate (I) and 2,2,6,6-tetramethyl-4-oxo-4-phenyl-1,4-azaphosphorinan-1-oxyl (II) were determined. CompoundIcrystallizes in the monoclinic space groupC2/cwith unit cell dimensionsa = 18.2967(7),b = 10.9413(6),c = 20.8714(13) Å, β = 90.79(1)° (at 115 K), andIIcrystallizes in the orthorhombic space groupPn21awitha = 8.076(1),b = 10.139(1),c = 17.894(1) Å. Intensity data were measured on a diffractometer at 115 K forIand at the room temperature forII. The structures were solved by a combination of heavy-atom and direct methods and refined toR = 0.036 (3968 reflections) forIand 0.039 (1451 reflections) forII.The azaphosphorinane ring adopts a chair conformation in both molecules, being flattened in the P part inIand in the N part inII. In moleculeIthe equatorial phenyl group is nearly parallel to the approximate plane of symmetry of the molecule, and the axial phenyl group is perpendicular to that plane. In moleculeIIthe P=O bond is axial and the phenyl group is equatorial. The CN(O)C group is not planar. The N—O bond makes an angle of 18.0(3)° with the CNC plane. The CNC angle of 129.3(3)° is larger than that found in nitroxypiperidine analogues.

ISSN:0008-4042    

DOI:10.1139/v83-076

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

2-Deoxy and 2,3-dideoxy-3-oxo-butyl-β-D-glycopyranosides were synthesized starting from tri-O-acetyl-D-glucal. These β compounds undergo Norrish II type photocyclization giving the corresponding hydroxyspiroketals without stereoselectivity but with greater reactivity than the α derivatives. Acidic epimerization of these spiro C-1 sugars leads to the α anomers in accord with known stereoelectronic effects.

ISSN:0008-4042    

DOI:10.1139/v83-077

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

A study of L- and K-selectride reductions of unsymmetrical cyclic anhydrides attached to six-membered rings and to bridged six-membered systems sheds a new light on the effect of the conformation of the substrate molecule on the regioselectivity of metal hydride reductions. Thus, in addition to intrinsic reactivity of the carbonyl group, the antiperiplanar effect, and steric congestion, the conformation of the parent molecule should be considered in predicting regioselectivity of nucleophilic additions to cyclic anhydrides.

ISSN:0008-4042    

DOI:10.1139/v83-078

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

The far-infrared spectra of 3-methylenecyclohexene, 4-methylenecyclohexene, and 1-methyl-3-methylenecyclohexene in the region of 80–400 cm−1are reported and interpreted mainly with a view to the two lowest out-of-plane deformations of the cyclohexene ring. Typical C-type band sequences are observed and interpreted in terms of ring inversion modes. Barriers to inversion are determined by means of a one-dimensional Hamiltonian with a quadratic-quartic potential function. Possible ground state geometries and forms of the inversion coordinates are discussed and compared to those thought to occur in the analogous cyclohexenones.

ISSN:0008-4042    

DOI:10.1139/v83-079

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

Cupric ion (or copper) or boron trifluoride promoted decomposition of ethyl 2-diazo-4-(pyrrol-1-yl)butanoate6produced mixtures of the title compound7andcisandtransethyl 4-(pyrrol-1-yl)buten-2-oates9and10. The formation of7by these processes represents the first reported instances of the intramolecular attack of an α-oxocarbenoid or a Lewis acid complexed α-diazoalkylcarboalkoxy function on the pyrrole nucleus.

ISSN:0008-4042    

DOI:10.1139/v83-080

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

The effect of water vapour and oxygen partial pressure on the thermal decomposition of hydrated chromium (III) oxide has been studied. A decrease in the water vapour partial pressure from 20 to 1 × 10−3 mm Hg has been found to produce a sharp increase in the specific surface area of the decomposition product (α-Cr2O3). Decomposition in an argon atmosphere leads to highly dispersed α-Cr2O3even at relatively high temperatures (400–500 °C).

ISSN:0008-4042    

DOI:10.1139/v83-081

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

D,L-Hamamelose (2-C-hydroxymethyl-D,L-ribose) has been synthesized from 2,2′-O-methylene-bis-D-glycerose by application of the sequential reactions aldol condensation, mercaptolysis, and demercaptalation. The structures of the intermediate thioglycosides ofD,L-hamamelose have been established by use of1Hmr and13Cmr spectroscopy. The exact composition of the equilibrium mixture ofD,L-hamamelose in aqueous solution has also been established by the concomitant use of1Hmr and13Cmr spectroscopy.D-Hamamelose has been obtained from theD,L-mixture by preferential crystallization.

ISSN:0008-4042    

DOI:10.1139/v83-082

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

Sedacrine, the major alkaloid ofSedumacre, is assigned structure5on the basis of spectroscopic and chemical evidence. Two minor bases, sedinone6and dihydrosedinine7, are described. Sedacrine5, sedinone6, dihydrosedinine7, and sedinine3are correlated. The absolute configurations of these alkaloids and that of sedacryptine2are established.

ISSN:0008-4042    

DOI:10.1139/v83-083

出版商:NRC Research Press    

年代:1983

数据来源: NRC

摘要:

Partial molar volumesof the Fe2+, Ni2+, Fe3+, Cr3+, Rh3+, and M(NH3)5OH3+(M = Cr, Co, Rh, Ir) aqueous ions have been obtained by extrapolation from density measurements at 298.15 K on the perchlorate salt solutions containing added HClO4where necessary to suppress hydrolysis or oxidation. The values for these high-spin aqua-ions and others in the literature can be represented satisfactorily for ionic chargesz = 1 through 4 bywhereis the absolute partial molar volume in cm3mol−1of Mz+(aq) relative tofor H+(aq), andris the Shannon radius in pm of Mz+with coordination numbernc. Volumes of activation ΔVex* for water exchange correlate inversely withwithin the series M2+(aq) and M(NH3)5OH23+(aq) at least, allowing predictions of ΔVex* to be made fromor the above equation. The physical origin of these correlations is considered.

ISSN:0008-4042    

DOI:10.1139/v83-084

出版商:NRC Research Press    

年代:1983

数据来源: NRC