Acta Chimica Sinica ›› 2013, Vol. 71 ›› Issue (08): 1118-1120.DOI: 10.6023/A13040417 Previous Articles     Next Articles

Communication

不对称α-烃基-α-羟基丙二酰胺衍生物的合成新方法

马菲, 陈建新   

  1. 山西师范大学化学与材料科学学院 临汾 041004
  • 投稿日期:2013-04-17 发布日期:2013-06-13
  • 通讯作者: 陈建新, E-mail: jjxxcc2002@yahoo.com E-mail:jjxxcc2002@yahoo.com
  • 基金资助:

    项目受山西省留学回国人员基金(No. 0713)、山西省自然科学基金(No. 2012011046-9)、山西师范大学基金(No. SD2011CXSY-12)资助.

Novel Method for Synthesis of Unsymmetrical α-Organyl-α-hydroxymalonamide Derivatives

Ma Fei, Chen Jianxin   

  1. College of Chemistry and Material Science, Shanxi Normal University, Linfen 041004
  • Received:2013-04-17 Published:2013-06-13
  • Supported by:

    Project supported by the Shanxi Province Foundation for Returness Overseas Scientists of China (No. 0713), the Natural Science Foundation of Shanxi Province of China (No. 2012011046-9), and the Foundation of Shanxi Normal University of China (No. SD2011CXSY-12).

Aldehydes may be directly converted to O-silyl-α-hydroxyamides by reaction with N-methoxymethyl-N-methyl- carbamoyl(trimethyl)silane. In an attempt to extend this chemistry, we found that N-methoxymethyl-N-methylcarbamoyl(trimethyl)silane did not react with α-ketoamides. So we started testing activity within the variety of carbonyl compounds towards N,N-dimethylcarbamoylsilane and found that the addition reaction of N,N-dimethylcarbamoyl(trimethyl)- silane with a series of N-methyl-N-methoxymethyl-α-ketoamides could afford good yields (71%~86%) of unsymmetrical α-organyl-α-hydroxymalonamide derivatives or unsymmetrical α-organyl-α-siloxymalonamide compounds. When 1.2 equiv. of a carbamoylsilane 1 was allowed to react with α-ketoamides 2 in anhydrous toluene solution under anhydrous conditions at ambient conditions or below, good yields of α-siloxyamides 3 were obtained, generally within long time. Their structures were characterized by elemental analysis, 1H NMR, 13C NMR and IR spectra. A novel method for synthesis of unsymmetrical α-organyl-α-hydroxymalonamide derivatives was provided. The experiments indicated that the steric environment was an important factor in the addition reaction since longer reaction time was needed both in case of 2b and 2c than in case of 2a, and the electronic effect influenced on the rate of the reaction since the yields were obtained about the same from a variety of aryl-α-ketoamides, the stronger donor ability of substituted group on the benzene ring of the aryl-α-ketoamides, the longer reaction time was needed. A reaction mechanism involving two intermediates is proposed, in which carbamoylsilane 1 can rearrange to its nucleophilic carbene form A, which attacked the carbonyl group of α-ketoamides to produce an unstable intermediate B, the subsequent silyl group transfer leads to corresponding the O-silylated adducts 3. The latter can be hydrolyzed to form the α-organyl-α-hydroxymalonamide derivatives 4.

Key words: carbamoylsilane, α-ketoamides, unsymmetrical α-organyl-α-hydroxymalonamide, addition reaction, synthesis