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  • 1
    Electronic Resource
    Electronic Resource
    Optisch aktive aromatische Spirane, 7. Mitt. Circulardichroismus optisch aktiver 5,5′-disubstituierter 2,2′-Spirobiindane (1978)
    Springer
    Monatshefte für Chemie 109 (1978), S. 987-999 
    Details
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Dipole-dipole coupling of the indane fragments in 5,5′-disubstituted 2,2′-spirobiindanes is predominantly responsible for the origin of optical activity in the1La-electronic transition only if both ligands exhibit strong interaction with the aromatic nuclei. This mechanism does not contribute essentially to the1Lb-Cotton effect. The band-splittings of the couplet as well as the rotational strengths of the transitions ofA andB symmetry-type in the1La-Cotton effect are in accordance with a rough calculatory estimation. The absolute configuration thus determined agrees with the chirality recently deduced by chemical methods. The rotational strengths of the1W-Cotton effect of the carbonyl derivatives4, 5, 12, 13, and15 located at appr. 320 nm are remarkably low. This can be explained on the basis of conformational considerations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00907320
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  • 2
    Electronic Resource
    Electronic Resource
    Zur Anwendung des Näherungsansatzes für Chiralitätsfunktionen an trisubstituierten 2,2′-Spirobiindanen (1981)
    Springer
    Monatshefte für Chemie 112 (1981), S. 405-409 
    Details
    ISSN: 1434-4475
    Keywords: 13C-Spectroscopy ; Ligand parameters ; Torsional angle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract From13C-NMR results, modified ligand parameters (λ-values) for theo-acetyl group in trisubstituted 2,2′-Spirobiindanes have been derived. With theses values a much better agreement between calculated and measured optical rotation is obtained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00900770
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  • 3
    Electronic Resource
    Electronic Resource
    Optisch aktive, aromatische Spirane, 8. Mitt.: Darstellung optisch aktiver, 5, 5′, 6′-trisubstituierter 2,2′-Spirobiindane bekannter Chiralität und enantiomerer Reinheit (1979)
    Springer
    Monatshefte für Chemie 110 (1979), S. 541-565 
    Details
    ISSN: 1434-4475
    Keywords: Configurational correlation ; 5-Ethylindanes ; 1 H-nmr spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Starting from (+) (2R) methyl 5′-ethyl-2,2′-spirobiindane-5-carboxylate of known enantiomeric purity 79 optically active, configurationally correlated 5,5′,6′-trisubstituted 2,2′-spirobiindanes (2–7) were prepared for the purpose of testing a “shortened polynomal Ansatz” for chirality functions. Their optical rotations and1H-nmr spectra are reported. In this context several 6-substituted 5-ethylindanes (1) were prepared as model compounds for synthetic transformations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00938359
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  • 4
    Electronic Resource
    Electronic Resource
    Optisch aktive, aromatische Spirane, 11. Mitt.: Synthese optisch aktiver mono- bis heptasubstituierter 5-Methyl- und 5-Ethyl-2,2′-spirobiindane und analoger Naphthalinderivate bekannter Chiralität und enantiomerer Reinheit (1981)
    Springer
    Monatshefte für Chemie 112 (1981), S. 801-823 
    Details
    ISSN: 1434-4475
    Keywords: Chirality function ; Circular dichroism ; Ligand parameters ; 5-Methyl and ethylindanes ; 1H-NMR spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Starting from optically active 5,5′-dimethyl, diethyl, and 5-ethyl-5′-methyl-2,2′-spirobiindane as well as from 5′-ethyl-spirobiindane-5-carboxylic ester of known enantiomeric purity and configuration 75 mono to polysubstituted 2,2′-spirobiindanes have been prepared. Amongst these are several compounds with rings anellated in the 6,7 (and 6′, 7′) positions, especially a spirohydrocarbon4 x with orthogonal naphthalene units the circular dichroism of which is reported and discussed. Several mono and disubstituted 5-methyl and ethylindanes (1,2) have been prepared as models for synthetic transformations in the spirobiindane series. From the molar rotations of symmetrically diacylated 5,5′-dimethyl and diethyl spirobiindanes (4a, 7b, 7c) empirical ligand parameters λ for acetyl and methoxycarbonyl were determined which gave much better results in the calculation of the rotations of appropriate spirobiindanes (with the “shortened polynomal Ansatz”) than the λ-values deduced previously from 5,5′-disubstituted spirobiindanes. The significance of these results is briefly discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00899783
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  • 5
    Electronic Resource
    Electronic Resource
    Optisch aktive, aromatische Spirane, 9. Mitt.: Überprüfung eines Näherungsansatzes für Chiralitätsfunktionen bei 5,5′,6′-trisubstituierten 2,2′-Spirobiindanen (1979)
    Springer
    Monatshefte für Chemie 110 (1979), S. 931-946 
    Details
    ISSN: 1434-4475
    Keywords: Ligand parameters ; chirality function ; 2,2′-Spirobiindanes ; 5,5′-disubstituted
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract In order to test the semiempirical value of chirality functions in their mathematically most simple form 23 new optically active 5,5′-disubstituted 2,2′-spirobiindanes1 of known chirality and enantiomeric purity were prepared. Thus a set of about hundred compounds is now available with altogether sixteen types of ligands (i.e. substituents including hydrogen); the experimental molar rotation of fifteen compounds is used to determine the value of a ligandspecific parameter occuring in the used chirality polynomial. According to theory this polynomial is an approximation for the total rotation of derivatives with ligands of three different types and it approximates an experimentally separable part of the rotation as far as compounds with four different ligands are concerned. The additional chirality component, occurring exclusively in the case of derivatives with four different types of ligands turns out to be relatively small but not vanishing. Accordingly, the molar rotation predicted by our method is very good for disubstituted spirobiindanes of type1 and rather good for others with three different types of ligands but is distinctly worse for those with four different ligands. The numerical trend, however, is clearly represented even in cases where our calculation in principle refers to a part of the phenomenon only and the predicted absolute configuration is in call cases in agreement with the experiment. An adequate criterion to judge the quality of our approximation is introduced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00906690
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  • 6
    Electronic Resource
    Electronic Resource
    Optisch aktive aromatische Spirane, 13. Mitt. (1985)
    Springer
    Monatshefte für Chemie 116 (1985), S. 789-799 
    Details
    ISSN: 1434-4475
    Keywords: Chirality function ; Chromatographic resolution ; Circular dichroism ; Configurational correlation ; Ligand parameters
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Several optically active title compounds were obtained from the 4′-acetyl-4-carboxylic acid2 or the 4,4′-diacetyl derivative4. (−)-2 was accessible by optical resolutionvia its (−)-α-phenethylamine salts, (+)- and (−)-4 as well as the enantiomeric methylesters3 (of2) were obtained by chromatography on triacetylcellulose in ethanol. The enantiomeric purities were established either from the chromatographic results or from the1H-NMR spectra of the phenethyl-amine saltes (via the diastereotopic acetyl protons). The chirality (−)-(2R) was deduced for all new compounds from a chemical correlation between (−)-2 and (−)-4 and on the basis of the CD spectra of the latter and of (−)-(2R)-17 of known absolute configuration. From the molar rotations of these 4,4′-disubstituted 2,2′-spirobiindanes (empirical) ligand parameters λ were determined which for some cases gave good results in the calculation of the rotations (using the “shortened Ansatz”). These results are briefly discussed especially in comparison with 5,5′-disubstituted 2,2′-spirobiindanes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809156
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  • 7
    Electronic Resource
    Electronic Resource
    Aromatische Spirane, 16. Mitt.: Darstellung von monound dianellierten 2,2′-Spirobiindan-1,1′-dionen (1989)
    Springer
    Monatshefte für Chemie 120 (1989), S. 597-621 
    Details
    ISSN: 1434-4475
    Keywords: Indane-1-one ; s-Hydrindacene-1-one ; Tetrahydrobenzoindane-1-one ; β-Keto esters ; Phthalaldehydic acid ; Spiro cyclisation ; 2,2′-Spirobiindane-1,1′-diones ; 1H-nmr spectra ; Mass spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The spiroketones19, 21, 24, 27, and31 were prepared by cyclisation of the dicarboxylic acids and their acid chlorides, resp., (18, 20, 22, 23, 25, 26, 28, and30) with polyphosphoric acid (PPA) or SnCl4. The latter compounds were synthesized by alkylation of the appropriate β-keto esters10, 11, 12, and13 with the “benzyl chlorides”14, 15, 16, and subsequent retro-Claisen-reaction. The spiro compounds21a and39 were obtained byPPA-cyclisation of the keto acids35 and38, which in turn were prepared by aldol-reaction of the ketoness-hydrindacen-1-on and9a with phthalaldehydic acid to the olefinic keto acids33 and36 followed by catalytic hydrogenation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00810848
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  • 8
    Electronic Resource
    Electronic Resource
    Aromatische Spirane, 12. Mitt. (1985)
    Springer
    Monatshefte für Chemie 116 (1985), S. 661-676 
    Details
    ISSN: 1434-4475
    Keywords: 5,6,7,8-Tetrahydrobenzo[f]indane and derivatives ; Mono- and bisanellation ; 2,2′-Spirobiindane ; 1H-nmr and mass spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The title compounds26 and32 were prepared by systematic mono- and bisanellation of sixmembered rings to the positions 5,6 and 5′,6′, resp. of 2,2′-spirobiindane.S E acylation and subsequent transformations of the acylgroups afforded many derivatives with substituents in positions 4 and 4′ of the parent compounds which were required for testing semiempirical values of chirality functions. 5,6,7,8-Tetrahydrobenz[f]indane (9) and several of its 4-substituted derivatives were prepared as models for the anellation and substitution reactions. Tentative preferred conformations of the 4-acylgroups could be deduced from1H-nmr spectra.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00798792
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  • 9
    Electronic Resource
    Electronic Resource
    Lanthanide induced shifts of sterically hindered aromatic carbonyl compounds oxomethylene-bridged, acetyl-, and formyl-2,2′-spirobiindanes (1987)
    Springer
    Monatshefte für Chemie 118 (1987), S. 1163-1175 
    Details
    ISSN: 1434-4475
    Keywords: 1 H-LIS model calculation ; LIS model for aromatic out of plane acetyl or formyl ; Conformational analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wurden die Lanthaniden-induzierten Verschiebungen (LIS) von 10 polysubstituierten 2,2′-Spirobiindanen mit einer Carbonylgruppe in Konjugation zu einem aromatischen Ring mittels derMcConnell-Robertson-Gleichung rechnerisch simuliert. Im Fall von Oxomethylen-überbrückten Derivaten (mit CO in einem mehr oder weniger starren Ring inkorporiert) ergaben sowohl das übliche „One Site” — als auch das „Two Site”-Modell gute Resultate. Im Fall sterisch gehinderter Acetyl- oder Formylderivate (beideortho-Positionen alkyl-substituiert) mußte ein neues Rechenmodell erstellt werden: die Carbonylgruppe erwies sich als etwa 30° aus der Benzolebene herausgedreht und die 4 möglichen Lagen (±30° und ±150°) zeigten dabei verschiedene Populationen. Das LIS-Programm mußte entsprechend modifiziert werden, um die Komplexierungsverhältnisse wiederzugeben.
    Notes: Abstract The lanthanide induced shift (LIS) data of 10 polysubstituted 2,2′-spirobiindanes with a carbonyl group in conjugation to an aromatic ring were simulated using theMcConnell-Robertson equation. In the case of oxomethylene-bridged derivates (with CO incorporated in a more or less rigid ring) the classical one site or two site models gave reasonable results. For sterically hindered acetyl or formyl derivates (bothortho positions alkyl-substituted) a new model was developed: the carbonyl group was found to be 30° out of the aromatic plane and the possible 4 positions (±30° and ±150°) turned out to be populated differently depending on theortho substituents. The LIS programme had to be modified to account for this situation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00811289
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  • 10
    Electronic Resource
    Electronic Resource
    Aromatische Spirane, 14. Mitt. Darstellung von 2,2′-Spirobi-(s-hydrindacen) und seinen Vorstufen (1987)
    Springer
    Monatshefte für Chemie 118 (1987), S. 627-657 
    Details
    ISSN: 1434-4475
    Keywords: s-Hydrindacene-1-one and derivates ; Mono- and bisanellation ; 2,2′-Spirobiindane ; 1H-nmr spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The title compound35 was prepared by catalytic reduction of the diones29 a and11a.29 a was synthesized by systematic anellation of fivemembered rings to the positions 5,6 and 5′,6′, resp., of 2,2′-spirobiindane. The preparation of11 a was achieved byFriedel-Crafts cyclisation of bis-(5-indanylmethyl)-malonic acid. s-Hydrindacene-1-one5 a was prepared as a precursor for the synthesis of11 a (see forthcoming publication) and its derivates as models for corresponding anellation and substitution reactions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809674
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