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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