Synthesis of chiral butenolides using amino-thiocarbamate-catalyzed asymmetric bromolactonization
摘要:
The asymmetric cyclization of 4,4-disubstituted 3-butenoic acids is studied. Amino-thiocarbamates are used as the catalysts and N-bromosuccinimide is used as the stoichiometric halogen source. The resulting gamma-butanolide products are readily converted into the corresponding gamma-butenolides (up to 58% ee) derivatives in one-pot. (C) 2014 Elsevier Ltd. All rights reserved.
Lithiated 4-Isopropyl-3-(methylthiomethyl)-5,5-diphenyloxazolidin-2-one: A Chiral Formyl Anion Equivalent for Enantioselective Preparations of 1,2-Diols, 2-Amino Alcohols, 2-Hydroxy Esters, and 4-Hydroxy-2-alkenoates
作者:Christoph Gaul、Kaspar Schärer、Dieter Seebach
DOI:10.1021/jo0155254
日期:2001.5.1
provide 4-hydroxy-2-alkenoates (Scheme 5). The scope and limitations of the new, overall enantioselective transformation are determined, and the readily recoveredchiralauxiliary used is compared with oxazolidinones of other substitution patterns (Scheme 7). The configuration of a number of products has been assigned by single-crystal X-ray diffraction (cf. Figure 5). These structures and similarities
Indole-Catalyzed Bromolactonization in Lipophilic Solvent: A Solid–Liquid Phase Transfer Approach
作者:Tao Chen、Thomas Jian Yao Foo、Ying-Yeung Yeung
DOI:10.1021/acscatal.5b01182
日期:2015.8.7
We have developed a novel indole-catalyzed bromolactonization of olefinic acids. The reaction could be conducted in lipophilic solvent through a solid liquid phase transfer mechanism. This catalytic protocol has been applied to the synthesis of base-sensitive bromolactones.
Albinati, Alberto; Bravo, Pierfrancesco; Ganazzoli, Fabio, Journal of the Chemical Society. Perkin transactions I, 1986, p. 1405 - 1416
Enantiodivergent syntheses of γ-substituted butenolides with tertiary and quaternary asymmetric centers
作者:Katsufumi Suzuki、Kohei Inomata
DOI:10.1016/s0040-4039(02)02711-9
日期:2003.1
Continuous nucleophilic addition with several organometallic reagents to tricyclic lactone (-)-1 proceeded diastereoselectively. Newly generated tertiary and quaternary asymmetric centers were controlled by the order in which the nucleophilic reagents were added. Using this methodology, enantiodivergent syntheses of several gamma-substituted butenolides with tertiary and quaternary asymmetric centers were established from a single chiral material. (C) 2003 Elsevier Science Ltd. All rights reserved.
Synthesis of chiral butenolides using amino-thiocarbamate-catalyzed asymmetric bromolactonization
作者:Chong Kiat Tan、Jun Cheng Er、Ying-Yeung Yeung
DOI:10.1016/j.tetlet.2014.01.009
日期:2014.2
The asymmetric cyclization of 4,4-disubstituted 3-butenoic acids is studied. Amino-thiocarbamates are used as the catalysts and N-bromosuccinimide is used as the stoichiometric halogen source. The resulting gamma-butanolide products are readily converted into the corresponding gamma-butenolides (up to 58% ee) derivatives in one-pot. (C) 2014 Elsevier Ltd. All rights reserved.