2--N''-<(R)-α-methylbenzyl>acetamide | 166903-14-6

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: 2--N''-<(R)-α-methylbenzyl>acetamide
• 英文别名: 2-N-(2,2'-dimethylpropyliden)amino-N'-<(R)-α-methylbenzyl>acetamide；2-(2,2-dimethylpropylideneamino)-N-[(1R)-1-phenylethyl]acetamide
• CAS: 166903-14-6
• 化学式: C₁₅H₂₂N₂O
• 分子量: 246.352
• InChiKey: ABYNFMFFOLNREI-GFCCVEGCSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.6
• 重原子数：
  18
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.47
• 拓扑面积：
  41.5
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  2--N''-<(R)-α-methylbenzyl>acetamide 在 正丁基锂 、 二异丙胺 作用下， 以 四氢呋喃 、 正己烷 、 甲苯 为溶剂， 反应 7.0h， 生成 (2S,5S,1'R)-1-benzoyl-2-tert-butyl-5-methyl-3-(α-methylbenzyl)-1,3-imidazolidin-4-one
  参考文献：
  名称：

  Highly Diastereoselective Alkylation of 1-Benzoyl-2-alkyl-3-(1'-methylbenzyl)imidazolidin-4-ones

  摘要：

  The synthetic utility of 2-alkyl-substituted 1,3-imidazolidinones for the enantioselective preparation of a-amino acids is now well documented in the literature. Incorporation of a N(3)-phenethyl group in these heterocycles leads to substantial enhancements in the diastereoselectivity of alkylation of the corresponding lithium enolates, so that stereoselectivities in the order of 19:1 to 49:1 are observed for 2-isopropyl and 2-tert-butyl derivatives, respectively. X-ray crystallographic analysis on five N(3)-phenethyl-substituted imidazolidinones provided evidence that the long-distance effect of that chiral moiety is the result of conformational changes provoked by steric interactions between the 2-alkyl and the N(3)-phenethyl groups. No additivity of the stereodirecting effects by the stereogenic centers at C(2) and C(1') was noticed, Thus, as it could have been anticipated from basic principles, intramolecular combinations of stereogenic centers do not necessarily lead to ''matched'' and ''mismatched'' joint stereoinducing effects.

  DOI：

  10.1021/jo00125a029
• 作为产物：
  描述：

  2--N''-<(R)-α-methylbenzyl>acetamide 在 palladium on activated charcoal 氢气 、 三乙胺 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 35.0 ℃ 、1.01 MPa 条件下， 反应 5.0h， 生成 2--N''-<(R)-α-methylbenzyl>acetamide
  参考文献：
  名称：

  Highly Diastereoselective Alkylation of 1-Benzoyl-2-alkyl-3-(1'-methylbenzyl)imidazolidin-4-ones

  摘要：

  The synthetic utility of 2-alkyl-substituted 1,3-imidazolidinones for the enantioselective preparation of a-amino acids is now well documented in the literature. Incorporation of a N(3)-phenethyl group in these heterocycles leads to substantial enhancements in the diastereoselectivity of alkylation of the corresponding lithium enolates, so that stereoselectivities in the order of 19:1 to 49:1 are observed for 2-isopropyl and 2-tert-butyl derivatives, respectively. X-ray crystallographic analysis on five N(3)-phenethyl-substituted imidazolidinones provided evidence that the long-distance effect of that chiral moiety is the result of conformational changes provoked by steric interactions between the 2-alkyl and the N(3)-phenethyl groups. No additivity of the stereodirecting effects by the stereogenic centers at C(2) and C(1') was noticed, Thus, as it could have been anticipated from basic principles, intramolecular combinations of stereogenic centers do not necessarily lead to ''matched'' and ''mismatched'' joint stereoinducing effects.

  DOI：

  10.1021/jo00125a029

文献信息

• Highly enantioselective synthesis of (R)- and (S)-2-amino-5-phosphonopentanoic acids [(R)- and (S)-AP5] via modified Seebach imidazolidinones
  作者：Oscar García-Barradas、Eusebio Juaristi

  DOI：10.1016/0040-4020(95)00091-l

  日期：1995.3

  isomers, (2R, 1′S)- and (2S, 1′R)-7, afforded the desired phosphorylated products 9 with ≥ 98% diastereoselectivity. Hydrolysis of the alkylated products proceeds under relatively mild conditions to give enantiomerically pure α-substituted α-amino acids. Thus, hydrolysis of (2R,5R,1′S)-9 and (2S,5S,1′R)-9 provided the physiologically important, enantiopure amino phosphonic acids (R)-AP5 and (S)-AP5.

  描述了四种新的立体异构体1-羰基苄氧基-2-叔丁基-3-（α-甲基苄基）-1,3-咪唑啉丁-4-酮的制备。这些手性甘氨酸衍生物的烯醇锂的烷基化以高非对映选择性进行。特别地，不同异构体（2 R，1 'S）-和（2 S，1'R）-7的反应，提供了具有≥98％非对映选择性的所需磷酸化产物9。烷基化产物的水解在相对温和的条件下进行，得到对映体纯的α-取代的α-氨基酸。因此，（2R，5R，1'S）-9和（2S，5S，1'R）-9的水解提供了生理上重要的对映体纯的氨基膦酸（R）-AP5和（S）-AP5。