98475-06-0Relevant articles and documents
Synthesis of α-sulfonyloxyketones via iodobenzene diacetate (PIDA)-mediated oxysulfonyloxylation of alkynes with sulfonic acids
Zhang, Yang,Tan, Hua,Liu, Weibing
, p. 54017 - 54020 (2017/12/05)
A simple yet powerful method to synthesize a variety of α-sulfonyloxyketones has been developed. This novel method can be applied for the direct oxysulfonyloxylation of alkynes with sulfonic acids to access a variety of α-sulfonyloxyketones. Compared to the reported methods for the application of PIDA, this study expands its application scope and uses it not only as the oxidant but also as the carrier of O to form the carbonyl group in the products. In addition, under the established conditions, this methodology not only exhibits a broad substrate scope but also demonstrates exclusive regioselectivity with substrates of 1,2-disubstituted internal alkynes.
Effective α-tosyloxylation of ketones using 1,1,1-trifluoro-2-iodoethane as catalyst
Zhang, Bijun,Han, Liuquan,Hu, Jiantao,Yan, Jie
supporting information, p. 3264 - 3270 (2015/10/06)
With 1,1,1-trifluoro-2-iodoethane as catalyst, a novel and efficient procedure has been developed for preparation of α-tosyloxyketones from ketones. In this protocol, 1,1,1-trifluoro-2-iodoethane is first oxidized by m-chloroperbenzoic acid to a hypervale
Enolate Structures Contributing to the Transition State for Nucleophilic Substitution on α-Substituted Carbonyl Compounds
Yousaf, T. I.,Lewis, E. S.
, p. 6137 - 6142 (2007/10/02)
The high SN2 reactivity of α-halocarbonyl compounds is explained by the lowering of the intrinsic barrier by a major contribution of enolate structure to the transition state.This theoretical conclusion is now shown experimentally.The evidence is as follows: (1) Change in structure of a leaving arenesulfonate ion does not change the rates of attack of benzenesulfonate ion by nearly as much as it changes the equilibrium constants.A charge on the transferring phenacyl group of -0.48 is deduced. (2) The ρ value (-3.9) for attack of substituted thiophenoxides on phenacyl bromide is much more negative than that for attack on methyl iodide (-1.8). (3) A related ρ value is found for reaction of 2,4,6-trimethylphenacyl bromide with thiophenoxides (-2.2), showing a lesser, but still large sensitivity to nucleophile structure where addition to the carbonyl is sterically forbidden.The enolate structure leaves the attacking or leaving nucleophiles with a single electron each instead of the unshared pairs.Thus, the enolate structure is emphesized if the leaving group and the nucleophile readily lose an electron.
