285-63-2Relevant articles and documents
Titanium and Cobalt Bimetallic Radical Redox Relay for the Isomerization of N -Bz Aziridines to Allylic Amides
Wood, Devin P.,Guan, Weiyang,Lin, Song
supporting information, p. 4213 - 4220 (2021/08/10)
Herein a bimetallic radical redox-relay strategy is employed to generate alkyl radicals under mild conditions with titanium(III) catalysis and terminated via hydrogen atom transfer with cobalt(II) catalysis to enact base-free isomerizations of N-Bz aziridines to N-Bz allylic amides. This reaction provides an alternative strategy for the synthesis of allylic amides from alkenes via a three-step sequence to accomplish a formal transpositional allylic amination.
Activation of carboxylic acids in asymmetric organocatalysis
Monaco, Mattia Riccardo,Poladura, Belen,Diaz De Los Bernardos, Miriam,Leutzsch, Markus,Goddard, Richard,List, Benjamin
, p. 7063 - 7067 (2014/07/08)
Organocatalysis, catalysis using small organic molecules, has recently evolved into a general approach for asymmetric synthesis, complementing both metal catalysis and biocatalysis.1 Its success relies to a large extent upon the introduction of novel and generic activation modes.2 Remarkably though, while carboxylic acids have been used as catalyst directing groups in supramolecular transition-metal catalysis,3 a general and well-defined activation mode for this useful and abundant substance class is still lacking. Herein we propose the heterodimeric association of carboxylic acids with chiral phosphoric acid catalysts as a new activation principle for organocatalysis. This self-assembly increases both the acidity of the phosphoric acid catalyst and the reactivity of the carboxylic acid. To illustrate this principle, we apply our concept in a general and highly enantioselective catalytic aziridine-opening reaction with carboxylic acids as nucleophiles. Activation by dimerization: There is still no general activation mode for carboxylic acids in organocatalysis. The formation of heterodimers between chiral phosphoric acid diesters and carboxylic acids can be used to activate and direct reactivity of the latter in asymmetric reactions. This novel principle has been applied to the ring-opening desymmetrization and kinetic resolution of aziridines leading to valuable amino alcohols.
Chemoenzymatic synthesis of optically active cis- and trans-2-(1H-Imidazol- 1-yl)cycloalkanamines
Alatorre-Santamaria, Sergio,Gotor-Fernandez, Vicente,Gotor, Vicente
experimental part, p. 1057 - 1063 (2011/04/17)
The preparation of enantiopure 2-(1H-imidazol-1-yl)cycloalkanamines has been studied by independent chemoenzymatic approaches. We first explored a route involving the enzymatic resolution of racemic cycloalkanol analogs for the preparation of the correspo