120158-06-7Relevant academic research and scientific papers
Investigation of the mechanism of racemization of litronesib in aqueous solution: Unexpected base-catalyzed inversion of a fully substituted carbon chiral center
Baertschi, Steven W.,Jansen, Patrick J.,Montgomery, Robert M.,Smith, William K.,Draper, Jerry R.,Myers, David P.,Houghton, Peter G.,Sharp, V. Scott,Guisbert, Andrea L.,Zhuang, Hong,Watkins, Michael A.,Stephenson, Gregory A.,Harris, Thomas M.
, p. 2797 - 2808 (2014)
Mitosis inhibitor (R)-litronesib (LY2523355) is a 1,3,4-thiadiazoline- bearing phenyl and N-(2-ethylamino)ethanesulfonamido-methyl substituents on tetrahedral C5. Chiral instability has been observed at pH 6 and above with the rate of racemization increas
Controlled Relay Process to Access N-Centered Radicals for Catalyst-free Amidation of Aldehydes under Visible Light
Chang, Sukbok,Jeon, Hyun Ji,Jung, Hoimin,Kim, Dongwook,Lee, Wongyu,Seo, Sangwon
, p. 495 - 508 (2021/01/28)
Nitrogen-centered radicals have attracted increasing attention as a versatile reactive intermediate for diverse C–N bond constructions. Despite the significant advances achieved in this realm, the controllable formation of such species under catalyst-free conditions remains highly challenging. Here, we report a new relay process involving the slow in situ generation of a photoactive N-chloro species via C–N bond formation, which subsequently enables mild and selective access to N-centered radicals under visible light conditions. The utility of this approach is demonstrated by the conversion of aldehydes to amides, employing N-chloro-N-sodio carbamates as a practical amidating source. This synthetic operation obviates the need for catalysts, external oxidants, and coupling reagents that are typically required in related processes, consequently allowing high functional group tolerance and excellent applicability for late-stage functionalization. Amides are an important class of structural motifs prevalently found in bioactive compounds and synthetic materials of great significance. Amidation of aldehydes has been established as an atom-efficient strategy for amide synthesis; however, current methods lack in applicability mainly due to the requirement of troublesome reagents. In this article, we describe an unconventional relay process to convert aldehydes to amides under catalyst-, oxidant-, and coupling-reagent-free conditions, which is enabled by the development of a new mechanistic platform that gives efficient and controllable access to N-centered radicals under visible light. A wide range of (hetero)aromatic and aliphatic aldehydes can be employed, including those derived from biologically relevant complex molecules. We anticipate that the accomplished methodological advances, combined with the unique mechanistic features, will lead to the widespread application of the present strategy in broad research fields. A catalyst-free approach for controlled access to N-centered radicals is described, which enables the conversion of aldehydes to amides via an unconventional relay process harnessing visible light. The key tactic relies on the use of photostable N-chloro-N-sodio-carbamate amidating reagent that leads to slow incorporations of a photoactive radical source via C–N formation and other involved intermediates thereafter. This methodology displays excellent applicability and sustainable chemistry credentials and, thus, holds a promise for finding broad applications.
Synthesis of acyl carbamates via four component Pd-catalyzed carbonylative coupling of aryl halides, potassium cyanate, and alcohols
Yin, Hongfei,De Almeida, Angelina M.,De Almeida, Mauro V.,Lindhardt, Anders T.,Skrydstrup, Troels
supporting information, p. 1248 - 1251 (2015/03/14)
A simple and mild method is demonstrated for assembling acyl carbamates through a base-free four-component Pd-catalyzed carbonylation of aryl halides in the presence of potassium cyanate and alcohols in a two-chamber system. This approach produces a wide range of aryl acyl carbamates in good to excellent yields from the corresponding aryl bromides or iodides with near-stoichiometric carbon monoxide. In addition, the method can be extended to the synthesis of primary amides thereby expanding the usefulness of cyanate as an ammonia equivalent.
Acidity of Benzoylcarbamates in Dimethyl Sulfoxide. Confirmation of Mixed N/O Alkylation in the Mitsunobu Reaction
Koppel, Ilmar,Koppel, Juta,Koppel, Ivar,Leito, Ivo,Pihl, Viljar,et al.
, p. 655 - 658 (2007/10/02)
Seventeen benzoyl-, 4-methoxybenzoyl-, and 4-nitrobenzoyl-carbamates have been synthesized via their corresponding isocyanates and their acidities determined in dimethyl sulfoxide solution.Their pKa values span an interval of nearly 5 pK units
A New Method for the Synthesis of Amides from Amines: Ruthenium Tetroxide Oxidation of N-Protected Alkylamines
Tanaka, Ken-Ichi,Yoshifuji, Shigeyuki,Nitta, Yoshihiro
, p. 3125 - 3129 (2007/10/02)
A simple synthetic method for the preparation of amides from the corresponding primary alkylamines was elaborated using ruthenium tetroxide (RuO4) oxidation as a key step.
