Cyclopropylcarbinyl-oxo-carboniumions. A solvolytic basis for the cyclopropylcarbinyl-oxo-carbonium ion

1970 ◽  
Vol 48 (13) ◽  
pp. 2146-2148 ◽  
Author(s):  
Bert Fraser-Reid ◽  
Bruno Radatus
Keyword(s):  
Silver Ion ◽  
Resonance Contribution ◽  
Conjugated Diene ◽  
Carbonium Ion ◽  
Neutral Media ◽  
Ion Assistance ◽  
Hydrolysis Of

Hydrolysis of 4,6-O-benzylidene-3-deoxy-3-C-(iodomethyl)-D-allal (1) in neutral buffered medium with or without silver ion assistance gives the cyclopropyl aldehyde 4 as the only product. Methanolysis of 1 gives an equal mixture of the α and β anomers of methyl 4,6-O-benzylidene-2,3-C-methylene-2,3-dideoxy-D-allopyranosides (6 and 7). These results indicate that the cyclopropylcarbinyl-oxo-carboniumion (2), is produced with unit efficiency in solvolyses in neutral media, and the formation of both diasteriomers (6 and 7) requires the complete absence of bicyclobutonium ion (9) resonance contribution to the stabilized intermediate, and implies a strong contribution from the oxo-carbonium ion 10. In basic media compound 1 undergoes quantitative dehydroiodination to the conjugated diene, 4,6-O-benzylidene-1,2,3-trideoxy-3-C-methylene-D-ribo-hex-1-enopyranose(8).

Rapid Capture and Hydrolysis of a Sulfur Mustard Gas in Silver-Ion-Exchanged Zeolite Y

2018 ◽  
Vol 10 (47) ◽  
pp. 40651-40660 ◽  
Author(s):  
Ye Rim Son ◽  
Min-Kun Kim ◽  
Sam Gon Ryu ◽  
Hyun Sung Kim
Keyword(s):  
Sulfur Mustard ◽  
Zeolite Y ◽  
Silver Ion ◽  
Mustard Gas ◽  
Hydrolysis Of

Silver ion assisted hydrolysis of 5,5-dichlorotetracyclo-[5.3.1.1.3,904,6]dodecane. A novel γ-lactone formation

1975 ◽  
Vol 16 (31) ◽  
pp. 2685-2688 ◽  
Author(s):  
Tadashi Sasaki ◽  
Shoji Eguchi ◽  
Masato Mizutani
Keyword(s):  
Silver Ion ◽  
Hydrolysis Of

Mechanism and Stereochemistry of the Hydrolysis of 4-Arylamino-1,2,3,4- tetrahydroquinaldines

1974 ◽  
Vol 52 (6) ◽  
pp. 884-887 ◽  
Author(s):  
T. P. Forrest ◽  
G. A. Dauphinee ◽  
W. F. Miles
Keyword(s):  
Nitrogen Atom ◽  
Equilibrium Mixture ◽  
Hydroxyl Group ◽  
Amino Group ◽  
Heterocyclic Nitrogen ◽  
Carbonium Ion ◽  
Kinetically Controlled ◽  
Leaving Group ◽  
Acid Catalyzed ◽  
Hydrolysis Of

Rates of acid-catalyzed hydrolysis of the benzylic amino group in stereoisomers of 4-arylamino-1,2,3,4-tetrahydroquinaldines have been determined by n.m.r. spectroscopy. Those isomers which have a pseudo-axial leaving group react more rapidly than those with a pseudo-equatorial leaving group, forming in each case the isomer with a pseudo-axial hydroxyl group as the kinetically controlled product. This product is converted in time to an equilibrium mixture of the two stereoisomeric alcohols. The reaction is inhibited by excess acid and appears to proceed through an intermediate carbonium ion which is stabilized by the heterocyclic nitrogen atom.

Studies in solvolysis. Part I. The neutral hydrolysis of some alkyl trifluoroacetates in water and deuterium oxide

1968 ◽  
Vol 46 (18) ◽  
pp. 2887-2894 ◽  
Author(s):  
June G. Winter ◽  
J. M. W. Scott
Keyword(s):  
Deuterium Oxide ◽  
Isotope Effects ◽  
Activation Process ◽  
Rate Data ◽  
Methyl Ethyl ◽  
Light Water ◽  
Carbonium Ion ◽  
Solvent Isotope ◽  
Hydrolysis Of ◽  
Solvent Isotope Effects

The temperature dependence of the rates of neutral hydrolysis of a series of alkyl trifluoroacetates (CF3COOR; R = methyl, ethyl, s-propyl, t-butyl) has been determined in both light and heavy water. From these studies the thermodynamic parameters (ΔH≠, ΔS≠) which characterize the activation process have been calculated. Sufficient rate data have been obtained in the case of the ethyl ester to calculate the heat capacity of activation (ΔCP≠) for the hydrolysis of this compound in light water. Both the entropies and enthalpies of activation as well as the solvent isotope effects are consistent with the proposal that the primary and secondary esters react by an acyl–oxygen BAc2 mechanism, in contrast to the tertiary ester, which appears to react either by a carbonium ion (SN1) process or by a route which combines both the BAc2 and SN1 paths.

The effect of silver ion on the alkaline hydrolysis of thiazolidines

1973 ◽  
Vol 14 (15) ◽  
pp. 1285-1288 ◽  
Author(s):  
R.R. Luhowy ◽  
R.F.W. Cieciuch ◽  
F. Meneghini
Keyword(s):  
Alkaline Hydrolysis ◽  
Silver Ion ◽  
Hydrolysis Of
Sign in / Sign up

Export Citation Format

Share Document