78317-99-4Relevant academic research and scientific papers
Trifluoroacetic acid catalyzed highly regioselective bromocyclization of styrene-type carboxylic acid
Chen, Tao,Yeung, Ying-Yeung
, p. 4571 - 4575 (2016)
A trifluoroacetic acid catalyzed highly 6-endo regioselective bromocyclization of styrene-type carboxylic acid has been developed. The resulting 3,4-dihydroisocoumarines are valuable building blocks in organic synthesis.
trans-Cyclooctenes as Halolactonization Catalysts
Einaru, Shunsuke,Shitamichi, Kenta,Nagano, Tagui,Matsumoto, Akira,Asano, Keisuke,Matsubara, Seijiro
, p. 13863 - 13867 (2018/09/27)
The strained olefins in trans-cyclooctenes serve as efficient catalysts for halolactonizations, including bromolactonizations and iodolactonizations. The trans-cyclooctene framework is essential for excellent catalytic performance, and the substituents also play important roles in determining efficiency. These results are the first demonstration of catalysis by a trans-cyclooctene.
Design of Chiral Bifunctional Dialkyl Sulfide Catalysts for Regio-, Diastereo-, and Enantioselective Bromolactonization
Nishiyori, Ryuichi,Tsuchihashi, Ayano,Mochizuki, Ayaka,Kaneko, Kazuma,Yamanaka, Masahiro,Shirakawa, Seiji
supporting information, p. 16747 - 16752 (2018/11/01)
Although a wide variety of chiral organocatalysts have been developed for asymmetric transformations, effective chiral dialkyl sulfide organocatalysts remain relatively rare and under-developed, despite the potential utility of dialkyl sulfide catalysts. Herein, we report the development of chiral bifunctional dialkyl sulfide catalysts possessing a urea moiety for regio-, diastereo-, and enantioselective bromolactonization. The importance of the bifunctional design of chiral sulfide catalysts was clearly demonstrated in the present work. The roles of both the sulfide and urea moieties of the catalyst were clarified based on the results of experimental and theoretical investigation.
An enantioselective approach toward 3,4-dihydroisocoumarin through the bromocyclization of styrene-type carboxylic acids
Chen, Jie,Zhou, Ling,Tan, Chong Kiat,Yeung, Ying-Yeung
experimental part, p. 999 - 1009 (2012/03/26)
A facile and enantioselective approach toward 3,4-dihydroisocoumarin was developed. The method involved an amino-thiocarbamate catalyzed enantioselective bromocyclization of styrene-type carboxylic acids, yielding 3-bromo-3,4-dihydroisocoumarins with good yields and ee's. 3-Bromo-3,4- dihydroisocoumarins are versatile building blocks for various dihydroisocoumarin derivatives in which the Br group can readily be modified to achieve biologically important 4-O-type and 4-N-type 3,4-dihydroisocoumarin systems. In addition, studies indicated that, by refining some parameters, the synthetically useful 5-exo phthalide products could be achieved with good yields and ee's.
