Go to  Advanced Search

Quantitative studies of hydrogen bonding in ortho-substituted phenols using proton magnetic resonance.

Show full item record

Files in this item

Files Size Format Description   View
UBC_1963_A6_7_A4 Q2.pdf 2.749Mb Adobe Portable Document Format   View/Open
 
Title: Quantitative studies of hydrogen bonding in ortho-substituted phenols using proton magnetic resonance.
Author: Allan, Ernest Albert
Degree Master of Science - MSc
Program Chemistry
Copyright Date: 1963
Subject Keywords Phenols; Nuclear magnetic resonance
Abstract: The chemical shift of protons in intramolecular hydrogen bonds has been measured in 41 ortho substituted phenol type compounds. The change in chemical shift " ΔσOH " on formation of these hydrogen bonds is taken as the difference between the infinite dilution chemical shift of the parent phenol compound in CCl₄ solution and the chemical shift measured for the proton in the intramolecular hydrogen bond. This change in chemical shift is correlated with the corresponding frequency shift " ΔνOH " in the -OH stretching region of the infra-red spectrum. The dilution chemical shift for the -OH proton in the o-halophenols has been investigated over a concentration range 1-5 mole % in CS₂ and a temperature region -53 to 107°C Using the infinite dilution shift values, the equilibrium constants of the cis-trans conversion were obtained. Values for δCIS, the chemical shift of the completely hydrogen bonded form; δ TRANS, the chemical shift of the unbonded form, and ΔH , the enthalpy of formation of the hydrogen bond, were also calculated. From these results a value for ΔH, the enthalpy of formation for the dimer was calculated, assuming that the major dimer species in solution was formed from the combination of a cis and trans bonded form. Temperature studies of the change in chemical shift of the -OH proton for 2,1,6-trihalosubstituted phenols is also reported. The temperature range in this case was 0°C to 111°0.
URI: http://hdl.handle.net/2429/38352
Series/Report no. UBC Retrospective Theses Digitization Project [http://www.library.ubc.ca/archives/retro_theses/]
Scholarly Level: Graduate

This item appears in the following Collection(s)

Show full item record

All items in cIRcle are protected by copyright, with all rights reserved.

UBC Library
1961 East Mall
Vancouver, B.C.
Canada V6T 1Z1
Tel: 604-822-6375
Fax: 604-822-3893