15775-60-7Relevant academic research and scientific papers
Mechanism of the reaction of amines with 5-[(Aryl- or Alkylamino) hydroxymethylene]-2,2-dimethyl-1,3-dioxane-4,6-diones in the presence of chlorotrimethylsilane (Me3SiCl)
Janikowska, Karolina,Makowiec, Slawomir,Rachon, Janusz
, p. 978 - 984 (2013/07/11)
Addition of chlorotrimethylsilane (Me3SiCl) to the mixture of a carbamoyl-substituted Meldrum's acid, i.e., a 5-[(arylamino)hydroxymethylene]-2, 2-dimethyl-1,3-dioxane-4,6-dione of type 1 and a secondary amine as nucleophile strongly accelerated the rate of their reaction. The reason for this phenomenon observed, during our previous research, remained, however, unclear. To elucidate the mechanism of this reaction, we assumed and verified three possible pathways for the action of Me3SiCl (cf. Scheme 2): The acceleration of the reaction is caused i) by formation of a O-trimethylsilylated Meldrum's acid of type 2, ii) by the silylated amine 3, or iii) by the presence of HCl liberated from Me3SiCl. The performed experiments revealed that the faster course of reaction is caused by the formation of N-trimethylsilylated amines of type 3. Copyright
TMSCL as a rate-accelerating additive in acylations of amines with 5-(α-AMINO-α′-Hydroxy)methylene meldrum acids
Janikowska, Karolina,Makowiec, Slawomir
experimental part, p. 975 - 988 (2012/02/03)
Aspects are presented of the acylation of amines, alcohols, and thiols with 5-(α-amino-α′-hydroxy)methylene Meldrum acids. We placed special emphasis on the acylation reaction of secondary amines with 5-(α-amino-α′-hydroxy)methylene Meldrum acids, which, because of their basicity, caused problems concerning salt formation with a Meldrum acid derivative. We found that secondary amines, which react at the slowest rate and give a poor yield with 5-(α-amino-α′-hydroxy)methylene Meldrum's acid, react quickly and with high yields with the same reagent in the presence 1 to 3 equivalents of TMSCl. Acylation with this derivative of Meldrum acid was optimized for such factors as reaction temperature, solvent polarity, and acidity of the environment. We have prepared a wide range of nonsymmetrical malononic acid diamids, esters, and thioesters of malonamic acid. Taylor & Francis Group, LLC.
