Some elimination reactions of hydroxy tosylates in the bornane series

1972 ◽  
Vol 25 (2) ◽  
pp. 361 ◽  
Author(s):  
RFM Cole ◽  
JM Coxon ◽  
MP Hartshorn
Keyword(s):  
Butyl Alcohol ◽  
Elimination Reactions

The reaction of cis-bornane-2,3-diol monotosylates with potassium t-butoxide in t-butyl alcohol gives exclusively the corresponding born-2-ene epoxide; trans-bornane-2,3-diol monotosylates give a ketone in addition to the epoxide.

Secondary α-deuterium kinetic isotope effects for the E2 reaction of the 2-phenylethyl halides with tert-butoxide ion in tert-butyl alcohol

1985 ◽  
Vol 63 (1) ◽  
pp. 100-102 ◽  
Author(s):  
Peter James Smith ◽  
Kanchugarakoppal S. Rangappa ◽  
Kenneth Charles Westaway
Keyword(s):  
Isotope Effects ◽  
Kinetic Isotope Effects ◽  
Order Rate Constant ◽  
Butyl Alcohol ◽  
Tert Butyl ◽  
Kinetic Isotope ◽  
Tert Butyl Alcohol ◽  
Elimination Reactions ◽  
Leaving Groups ◽  
High Base

Secondary α-deuterium kinetic isotope effects have been determined for the elimination reactions of 2-phenylethyl halides with tert-butoxide in tert-butyl alcohol at 40 °C in the presence and absence of the crown ether 18C6. The second-order rate constant k2 and the normal (kH/kD)α effect remained constant when the tert-butoxide concentration was varied for reaction of the iodo and bromo compounds. However, both the magnitude of k2 and the secondary α-deuterium isotope effect were significantly dependent on [t-BuO−] when chlorine and fluorine are the leaving groups. It is noteworthy that (kH/kD)α is inverse for the reaction of both the chloro and fluoro compounds at "low" base concentrations and normal at "high" base concentrations. These results are discussed in terms of both syn- and anti-elimination pathways promoted by various associated and dissociated base species. It is suggested that the (kH/kD)α effect may be useful as a criterion for determining the stereochemistry of E2 elimination reactions.

Isotope effect studies on elimination reactions. VII. The stereochemistry of elimination from 2-phenylethylammonium ions

1970 ◽  
Vol 48 (1) ◽  
pp. 133-137 ◽  
Author(s):  
A. N. Bourns ◽  
A. C. Frosst
Keyword(s):  
Magnetic Resonance ◽  
Isotope Effect ◽  
Proton Magnetic Resonance ◽  
Spectroscopic Analysis ◽  
Butyl Alcohol ◽  
Magnetic Resonance Spectroscopic Analysis ◽  
Solvent Systems ◽  
Elimination Reactions

The stereochemistry of the base-promoted elimination reactions of 2-phenylethyltrimethylammonium and 2-phenylethyldimethylanilinium ions has been investigated using both ethoxide ion in ethanol and t-butoxide in t-butyl alcohol as base-solvent systems. The proton magnetic resonance spectroscopic analysis of the deuterated styrene products formed from the reactions of the threo-2-phenylethylammonium-1,2-d2 ions established that elimination proceeds more than 95% by an anti process.

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