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Updated: Apr 23, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Enantioselective, desymmetrizing, bromolactonization reactions of symmetric olefinic dicarboxylic acids
Kenichi Murai1, Junki Nakajima, Akira Nakamura
1Graduate School of Pharmaceutical Sciences, Osaka University, 1-6, Yamada-oka, Suita, Osaka, 565-0871 (Japan), Fax: (+81) 6-6879-8229. murai@phs.osaka-u.ac.jp.
Abstract:
The results of studies leading to the development of enantioselective desymmetrizing, bromolactonization reactions of symmetric olefinic dicarboxylic acids, which are promoted by a C3 -symmetric trisimidazoline catalyst, are described. These processes generated carboxylic-acid-containing bromolactones in moderately high enantiomeric excesses. The results of optimization studies showed that reactions in a mixed solvent system of toluene and acetone proceeded with the highest levels of enantioselectivity. NMR studies probing the interactions between the catalyst and dicarboxylic acid substrates, as well as the effect of acetone on the stereochemistry of the process, are also described.
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