RecordNumber
42
Doc. No.
82A
Call. No.
82A
Author
Dabbagh, Hossien A.,Franzus, Boris,Huang, Thomas T. s.
Title of Article
Deuterium isotope studies of the dehydration alcohols by reaction with triphenylphosphine-tetrachloromethane
Title Of Periodical
TETRAHEDRON
VolumNumber
V.47, N.6
Date
(1991)
Page
P.949-960
Descriptors
Isotop effect streoselectivitg,Elimination,Substilution reges selectivitg
Abstract
The reactions of 2-butanol, 2-butanol-2d1, erythro-2-butanol-3d1 (EB), 2-methyl-2-propanol (2M2P), and 1,1,1,3,3,3-hexadeuterio-2-propanol (HDMP), respectively, with CC4, and ph3p in a polar or non-polar solvent in the temperature range of 36-85 C was studied. For 2-butanol the fraction of dehydration products increased with temperature, the opposite temperature effect was observed for (2M2p).Dehydration was the dominant pathway for (2M2p) (85-95,) but substitution (of OH by C) was dominant for 2-butanol (75-95,). Deuterium retention in thebutenes from the conversion of (EB) indicated that 98,or more of the dehydration followed an antielimination pathway, and there was a preference for Saytzeff elimination. An isotope effect for deuterium elimination (KH/KD)for the alkene-forming step for (EB) and (HDMP)was about 2.0 and neither temperature nor solvent polarity appeared to have an effect on (KH/KD) in the range investigated. Surprisingly,there was an isotope effect for the relative rate of the formation of alkyl halide from (ED)but not from (HDMP).
Indexer
1376/08
IndexDate
Shahsvary
اطلاعات ثبت
GN103049