614-43-7Relevant academic research and scientific papers
1,3-Dibromo-5,5-dimethylhydantoin as a Precatalyst for Activation of Carbonyl Functionality
?ebular, Klara,Bo?i?, Bojan ?.,Stavber, Stojan
supporting information, (2019/08/01)
Activation of carbonyl moiety is one of the most rudimentary approaches in organic synthesis and is crucial for a plethora of industrial-scale condensation reactions. In esterification and aldol condensation, which represent two of the most important reactions, the susceptibility of the carbonyl group to nucleophile attack allows the construction of a variety of useful organic compounds. In this context, there is a constant need for development of and improvement in the methods for addition-elimination reactions via activation of carbonyl functionality. In this paper, an advanced methodology for the direct esterification of carboxylic acids and alcohols, and for aldol condensation of aldehydes using widely available, inexpensive, and metal-free 1,3-dibromo-5,5-dimethylhydantoin under neat reaction conditions is reported. The method is air- and moisture-tolerant, allowing simple synthetic and isolation procedures for both reactions presented in this paper. The reaction pathway for esterification is proposed and a scale-up of certain industrially important derivatives is performed.
Esterification of aryl/alkyl acids catalysed by n-bromosuccinimide under mild reaction conditions
?ebular, Klara,Bo?i?, Bojan ?.,Stavber, Stojan
, (2018/09/10)
N-halosuccinimides (NXSs) are well-known to be convenient, easily manipulable and low-priced halogenation reagents in organic synthesis. In the present work, N-bromosuccinimide (NBS) has been promoted as the most efficient and selective catalyst among the NXSs in the reaction of direct esterification of aryl and alkyl carboxylic acids. Comprehensive esterification of substituted benzoic acids, mono-, di- and tri-carboxy alkyl derivatives has been performed under neat reaction conditions. The method is metal-free, air- and moisture-tolerant, allowing for a simple synthetic and isolation procedure as well as the large-scale synthesis of aromatic and alkyl esters with yields up to 100%. Protocol for the recycling of the catalyst has been proposed.
Selective mono-fluorination of diols via a cyclic acetal of N,N-diethyl-4-methoxybenzamide
Suwada, Mitsuhiro,Fukuhara, Tsuyoshi,Hara, Shoji
, p. 1121 - 1125 (2008/02/10)
Selective mono-fluorination of 1,2- and 1,3-diols was achieved using N,N-diethyl-4-methoxybenzamide diethyl acetal and Et3N-3HF. The reaction proceeds through a cyclic acetal of the benzamide, and only one hydroxy group was fluorinated and anot
Reactions of monoesters of ethylene glycol with N,N-diethyl-1,1,2,3,3,3-hexafluoropropylamine
Watanabe,Fujita,Sakamoto,Kuramochi,Kitazume
, p. 361 - 372 (2007/10/02)
By reaction with 1,1,2,3,3,3-hexafluoropropyldiethylamine (PPDA), various monoesters of ethylene glycol gave a mixture of corresponding monofluorides and 2,3,3,3-tetrafluoropropionate esters. The antimicrobial properties of these fluorine compounds for a spent coolant were examined.
CHEMOSELECTIVE FLUORINATION FOR PRIMARY ALCOHOLS
Shimizu, Makoto,Nakahara, Yuko,Yoshioka, Hirosuke
, p. 4207 - 4210 (2007/10/02)
Primary alcohols and their silylated derivatives are selectively fluorinated by tetraalkylammonium fluoride and aryl (or alkyl) sulfonyl fluoride.
