The catalytic activity of a simple aminoalcohol that contains a bulky super silyl group [i.e., tris(trimethylsilyl)silyl (TTMSS)] bonded to the oxygen atom at the γ-position along with a primary amine moiety was examined in the enantioselective1,3-dipolarcycloaddition of nitrones to α,β-unsaturatedaldehydes. The organocatalyst successfully provided optically active isoxazolidines in good chemical
reaction conditions for the asymmetric organocatalytic 1,3-dipolarcycloaddition of a nitrone with α,β-unsaturated aldehydes. The influence of ionic liquids, high-pressure conditions, ultrasound, microwave irradiation and ball-milling was tested as well as the flow process. Because of the low reactivity of the nitrone and unsaturated aldehydes in the 1,3-dipolarcycloaddition, cycloadducts were isolated
Synthesis and application of a recyclable ionic liquid-supported imidazolidinone catalyst in enantioselective 1,3-dipolar cycloaddition
作者:Zhi-Liang Shen、Kau Kiat Kelvin Goh、Colin Hong An Wong、Wan-Yi Loo、Yong-Sheng Yang、Jun Lu、Teck-Peng Loh
DOI:10.1039/c2cc31830j
日期:——
The synthesis of recyclable ionic liquid-supported imidazolidinone catalyst I and its application in 1,3-dipolar cycloaddition of nitrone with alpha,beta-unsaturated aldehyde with high performance were described. Most importantly, the catalyst I can be recovered and recycled for up to five runs without observing significant decrease in catalytic activity.
Enantioselective 1,3-dipolar cycloadditions of nitrones with unsaturated aldehydes promoted by a recyclable tetraarylphosphonium supported imidazolidinone catalyst
作者:Xin Nie、Cuifen Lu、Zuxing Chen、Guichun Yang、Junqi Nie
DOI:10.1016/j.molcata.2014.06.015
日期:2014.11
The tetraarylphosphonium supported chiral imidazolidinone catalyzes the enantioselective1,3-dipolarcycloadditions of nitrones and α,β-unsaturatedaldehydes to provide isoxazolidine aldehydes in good yields with excellent diastereo- and enantioselectivities. Most importantly, the tetraarylphosphonium supported imidazolidinone catalyst can be readily recovered and recycled for further transformations
The highly enantioselective 1,3-dipolar cycloaddition of alkyl glyoxylate-derived nitrones to E-crotonaldehyde catalyzed by hybrid diamines
作者:Łukasz Weseliński、Edyta Słyk、Janusz Jurczak
DOI:10.1016/j.tetlet.2010.11.015
日期:2011.1
1,3-Dipolarcycloaddition of alkyl glyoxylate-derived nitrones to E-crotonaldehyde can be catalyzed by hybrid diamines, obtained from (S)-BINAM and l-α-amino acids. The hybrid of (S)-BINAM and l-Phe was found to be the best organocatalyst. Products were obtained in good yield and diastereoselectivity as well as high enantioselectivity (82–91% ee). Subsequent transformations into functionalized pyrrolidinones