Hydration of an Acid Anhydride

The Water Complex of Acetic Sulfuric Anhydride

C. J. Smith, Anna K. Huff, Rebecca B. Mackenzie, Kenneth R Leopold

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The complex formed from acetic sulfuric anhydride (CH 3 COOSO 2 OH, ASA) and water has been observed by pulsed nozzle Fourier transform microwave spectroscopy. ASA was formed in situ in the supersonic jet via the reaction of SO 3 and CH 3 COOH, and subsequently complexed with water using a concentric, dual injection needle that allows reagents to be introduced at different points along the expansion axis. Spectroscopic constants for the parent, fully deuterated, and CH 3 13 COOSO 2 OH species are reported. Both A and E internal rotor states have been observed and analyzed. The fitted internal rotation barrier of the methyl group is 219.598(21) cm -1 for the parent species, indicating that complexation with water lowers the internal rotation barrier of the methyl group by 9% relative to that of the free ASA. M06-2X/6-311++G(3df,3pd) calculations predict at least two distinct isomeric forms of ASA···H 2 0. Spectroscopic constants for the observed species agree with those for the lower energy isomer in which the water inserts into the intramolecular hydrogen bond of the ASA monomer. CCSD(T)/CBS(D-T) calculations place the binding energy of this isomer at 13.3 kcal/mol below that of the isolated ASA and H 2 O monomers. The calculations further indicate that the doubly hydrogen bonded complex CH 3 COOH···H 2 SO 4 , which contains the hydrolysis products of ASA, lies even lower in energy, but this species was not observed in this study. This system represents the first stage of microsolvation of an acid anhydride, and the results indicate that a single water molecule does not induce spontaneous hydrolysis in a cold molecular cluster.

Original languageEnglish (US)
Pages (from-to)4549-4554
Number of pages6
JournalJournal of Physical Chemistry A
Volume122
Issue number18
DOIs
StatePublished - May 10 2018

Fingerprint

acetylsalicylic acid
Anhydrides
anhydrides
Acetic Acid
Hydration
hydration
acids
Acids
Water
methylidyne
water
Isomers
Hydrolysis
Monomers
Microwave spectroscopy
hydrolysis
isomers
monomers
Complexation
Binding energy

PubMed: MeSH publication types

  • Journal Article

Cite this

Hydration of an Acid Anhydride : The Water Complex of Acetic Sulfuric Anhydride. / Smith, C. J.; Huff, Anna K.; Mackenzie, Rebecca B.; Leopold, Kenneth R.

In: Journal of Physical Chemistry A, Vol. 122, No. 18, 10.05.2018, p. 4549-4554.

Research output: Contribution to journalArticle

Smith, C. J. ; Huff, Anna K. ; Mackenzie, Rebecca B. ; Leopold, Kenneth R. / Hydration of an Acid Anhydride : The Water Complex of Acetic Sulfuric Anhydride. In: Journal of Physical Chemistry A. 2018 ; Vol. 122, No. 18. pp. 4549-4554.
@article{a1580f8d0ef84e61945ae6ea27a5b130,
title = "Hydration of an Acid Anhydride: The Water Complex of Acetic Sulfuric Anhydride",
abstract = "The complex formed from acetic sulfuric anhydride (CH 3 COOSO 2 OH, ASA) and water has been observed by pulsed nozzle Fourier transform microwave spectroscopy. ASA was formed in situ in the supersonic jet via the reaction of SO 3 and CH 3 COOH, and subsequently complexed with water using a concentric, dual injection needle that allows reagents to be introduced at different points along the expansion axis. Spectroscopic constants for the parent, fully deuterated, and CH 3 13 COOSO 2 OH species are reported. Both A and E internal rotor states have been observed and analyzed. The fitted internal rotation barrier of the methyl group is 219.598(21) cm -1 for the parent species, indicating that complexation with water lowers the internal rotation barrier of the methyl group by 9{\%} relative to that of the free ASA. M06-2X/6-311++G(3df,3pd) calculations predict at least two distinct isomeric forms of ASA···H 2 0. Spectroscopic constants for the observed species agree with those for the lower energy isomer in which the water inserts into the intramolecular hydrogen bond of the ASA monomer. CCSD(T)/CBS(D-T) calculations place the binding energy of this isomer at 13.3 kcal/mol below that of the isolated ASA and H 2 O monomers. The calculations further indicate that the doubly hydrogen bonded complex CH 3 COOH···H 2 SO 4 , which contains the hydrolysis products of ASA, lies even lower in energy, but this species was not observed in this study. This system represents the first stage of microsolvation of an acid anhydride, and the results indicate that a single water molecule does not induce spontaneous hydrolysis in a cold molecular cluster.",
author = "Smith, {C. J.} and Huff, {Anna K.} and Mackenzie, {Rebecca B.} and Leopold, {Kenneth R}",
year = "2018",
month = "5",
day = "10",
doi = "10.1021/acs.jpca.8b02432",
language = "English (US)",
volume = "122",
pages = "4549--4554",
journal = "Journal of Physical Chemistry A",
issn = "1089-5639",
publisher = "American Chemical Society",
number = "18",

}

TY - JOUR

T1 - Hydration of an Acid Anhydride

T2 - The Water Complex of Acetic Sulfuric Anhydride

AU - Smith, C. J.

AU - Huff, Anna K.

AU - Mackenzie, Rebecca B.

AU - Leopold, Kenneth R

PY - 2018/5/10

Y1 - 2018/5/10

N2 - The complex formed from acetic sulfuric anhydride (CH 3 COOSO 2 OH, ASA) and water has been observed by pulsed nozzle Fourier transform microwave spectroscopy. ASA was formed in situ in the supersonic jet via the reaction of SO 3 and CH 3 COOH, and subsequently complexed with water using a concentric, dual injection needle that allows reagents to be introduced at different points along the expansion axis. Spectroscopic constants for the parent, fully deuterated, and CH 3 13 COOSO 2 OH species are reported. Both A and E internal rotor states have been observed and analyzed. The fitted internal rotation barrier of the methyl group is 219.598(21) cm -1 for the parent species, indicating that complexation with water lowers the internal rotation barrier of the methyl group by 9% relative to that of the free ASA. M06-2X/6-311++G(3df,3pd) calculations predict at least two distinct isomeric forms of ASA···H 2 0. Spectroscopic constants for the observed species agree with those for the lower energy isomer in which the water inserts into the intramolecular hydrogen bond of the ASA monomer. CCSD(T)/CBS(D-T) calculations place the binding energy of this isomer at 13.3 kcal/mol below that of the isolated ASA and H 2 O monomers. The calculations further indicate that the doubly hydrogen bonded complex CH 3 COOH···H 2 SO 4 , which contains the hydrolysis products of ASA, lies even lower in energy, but this species was not observed in this study. This system represents the first stage of microsolvation of an acid anhydride, and the results indicate that a single water molecule does not induce spontaneous hydrolysis in a cold molecular cluster.

AB - The complex formed from acetic sulfuric anhydride (CH 3 COOSO 2 OH, ASA) and water has been observed by pulsed nozzle Fourier transform microwave spectroscopy. ASA was formed in situ in the supersonic jet via the reaction of SO 3 and CH 3 COOH, and subsequently complexed with water using a concentric, dual injection needle that allows reagents to be introduced at different points along the expansion axis. Spectroscopic constants for the parent, fully deuterated, and CH 3 13 COOSO 2 OH species are reported. Both A and E internal rotor states have been observed and analyzed. The fitted internal rotation barrier of the methyl group is 219.598(21) cm -1 for the parent species, indicating that complexation with water lowers the internal rotation barrier of the methyl group by 9% relative to that of the free ASA. M06-2X/6-311++G(3df,3pd) calculations predict at least two distinct isomeric forms of ASA···H 2 0. Spectroscopic constants for the observed species agree with those for the lower energy isomer in which the water inserts into the intramolecular hydrogen bond of the ASA monomer. CCSD(T)/CBS(D-T) calculations place the binding energy of this isomer at 13.3 kcal/mol below that of the isolated ASA and H 2 O monomers. The calculations further indicate that the doubly hydrogen bonded complex CH 3 COOH···H 2 SO 4 , which contains the hydrolysis products of ASA, lies even lower in energy, but this species was not observed in this study. This system represents the first stage of microsolvation of an acid anhydride, and the results indicate that a single water molecule does not induce spontaneous hydrolysis in a cold molecular cluster.

UR - http://www.scopus.com/inward/record.url?scp=85046484930&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85046484930&partnerID=8YFLogxK

U2 - 10.1021/acs.jpca.8b02432

DO - 10.1021/acs.jpca.8b02432

M3 - Article

VL - 122

SP - 4549

EP - 4554

JO - Journal of Physical Chemistry A

JF - Journal of Physical Chemistry A

SN - 1089-5639

IS - 18

ER -