Axial and equatorial hydrogen bonds in pentamethylene sulfide···hydrogen chloride complex

TY - JOUR

T1 - Axial and equatorial hydrogen bonds in pentamethylene sulfide···hydrogen chloride complex

AU - Sanz, ME

AU - Lopez, JC

AU - Alonso, JL

PY - 1999/11/5

Y1 - 1999/11/5

N2 - Axial and equatorial hydrogen bonds have been observed in the heterodimer formed between pentamethylene sulfide and hydrogen chloride in a pulsed supersonic expansion by using Fourier transform microwave spectroscopy. The ground-state rotational spectra of the isotopic species ((C5H10S)-S-32, (HCl)-Cl-35), ((C5H10S)-S-32, (HCl)-Cl-37), ((C5H10S)-S-32, (DCl)-Cl-35), and ((C5H10S)-S-34, (HCl)-Cl-35) have been analyzed for the equatorial conformer, and the first three of these for the axial form in the frequency range 6-18 GHz. Interpretation of the rotational constants led to the conclusion that the observed complexes have C-s symmetry with the hydrogen chloride pointing to the domain of axial or equatorial lane pairs at the sulfur atom. The equatorial form has been found to be the most stable one, in contrast to the observation in the related tetrahydropyran ... HCl complex. The conformational preference is discussed in the context of second-order interactions.

AB - Axial and equatorial hydrogen bonds have been observed in the heterodimer formed between pentamethylene sulfide and hydrogen chloride in a pulsed supersonic expansion by using Fourier transform microwave spectroscopy. The ground-state rotational spectra of the isotopic species ((C5H10S)-S-32, (HCl)-Cl-35), ((C5H10S)-S-32, (HCl)-Cl-37), ((C5H10S)-S-32, (DCl)-Cl-35), and ((C5H10S)-S-34, (HCl)-Cl-35) have been analyzed for the equatorial conformer, and the first three of these for the axial form in the frequency range 6-18 GHz. Interpretation of the rotational constants led to the conclusion that the observed complexes have C-s symmetry with the hydrogen chloride pointing to the domain of axial or equatorial lane pairs at the sulfur atom. The equatorial form has been found to be the most stable one, in contrast to the observation in the related tetrahydropyran ... HCl complex. The conformational preference is discussed in the context of second-order interactions.

KW - conformation analysis

KW - hydrogen bonds

KW - microwave spectroscopy

KW - rotational spectroscopy

KW - COMPLEX

KW - SPECTRA

U2 - 10.1002/(SICI)1521-3765(19991105)5:11<3293::AID-CHEM3293>3.0.CO;2-#

DO - 10.1002/(SICI)1521-3765(19991105)5:11<3293::AID-CHEM3293>3.0.CO;2-#

M3 - Article

SN - 0947-6539

VL - 5

SP - 3293

EP - 3298

JO - CHEMISTRY

JF - CHEMISTRY

IS - 11

M1 - N/A

ER -