A new case of induced helical chirality in a bichromophoric system: absolute configuration of transparent and flexible diols from the analysis of the electronic circular dichroism spectra of the corresponding di(1-naphthyl)ketals.
Di(1-naphthyl)ketals of 1, n-diols show couplet effects allied to the (1)B naphthalene transition in their CD spectra. This means that they assume a conformation with a prevailing sense of twist of the naphthalene rings, imposed by the absolute configuration (AC) of the starting diols and by the nature of the R 1 groups. A positive couplet for aliphatic diols is a probe of ( R, R), AC while the opposite sign is found for ( R, R) aromatic diols.
Tartaglia
Sabina
S
Dipartimento di Chimica, Università della Basilicata, via N. Sauro 85, 85100 Potenza, Italy.
Pace
Francesca
F
Scafato
Patrizia
P
Rosini
Carlo
C