Conformational preferences of chiral molecules: free jet rotational spectrum of 1-phenyl-1-propanol.
The rotational spectra of normal and O-d species of the two most stable conformers of chiral 1-phenyl-1-propanol, obtained by free jet millimetre-wave absorption spectroscopy reveal that both conformers are stabilized by a O-H[dot dot dot]pi interaction, and have the Calpha-Cbeta-bond oriented nearly perpendicular to the plane of the benzene ring. The methyl group is trans with respect to the phenyl group for the most stable conformer (T), while it is gauche with respect to the phenyl group and entgegen with respect to the hydroxyl group for the second most stable conformer (GE). The energy difference (E(GE)-E(T)) was estimated to be 50(50) cm(-1) from relative intensity measurements.
Giuliano
Barbara M
BM
Dipartimento di Chimica G. Ciamician dell' Università, Via Selmi 2, I-40126, Bologna, Italy.
Ottaviani
Paolo
P
Favero
Laura B
LB
Caminati
Walther
W
Grabow
Jens-Uwe
JU
Giardini
Anna
A
Satta
Mauro
M