(S)-4-aza-5-iso-butyl-6-(tert-butyldimethylsilanyloxy)-4-(p-toluenesulfonyl)hexanal dimethyl acetal | 903516-23-4

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: (S)-4-aza-5-iso-butyl-6-(tert-butyldimethylsilanyloxy)-4-(p-toluenesulfonyl)hexanal dimethyl acetal
• 英文别名: N-[(2S)-1-[tert-butyl(dimethyl)silyl]oxy-4-methylpentan-2-yl]-N-(3,3-dimethoxypropyl)-4-methylbenzenesulfonamide
• CAS: 903516-23-4
• 化学式: C₂₄H₄₅NO₅SSi
• 分子量: 487.777
• InChiKey: PBLYJDKTAILGIO-NRFANRHFSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.43
• 重原子数：
  32
• 可旋转键数：
  14
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.75
• 拓扑面积：
  73.4
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为反应物：
  描述：

  (S)-4-aza-5-iso-butyl-6-(tert-butyldimethylsilanyloxy)-4-(p-toluenesulfonyl)hexanal dimethyl acetal 在 盐酸 、 偶氮二异丁腈 、 水 、 三正丁基氢锡 、 三乙胺 、 苯甲酸 、 lithium bromide 作用下， 以 四氢呋喃 、 二氯甲烷 、 甲苯 为溶剂， 反应 62.0h， 生成 (2R,4S)-2-isobutyl-4-(tert-butoxycarbonylmethyl)-1-(p-toluenesulfonyl)piperidine
  参考文献：
  名称：

  Synthesis of 2,4-Disubstituted Piperidines via Radical Cyclization:  Unexpected Enhancement in Diastereoselectivity with Tris(trimethylsilyl)silane

  摘要：

  [GRAPHICS]A novel approach to 2,4-disubstituted piperidines is reported, involving the radical cyclization of 7-substituted-6-aza-8-bromooct-2-enoates. Cyclization with tributyltin hydride affords the trans piperidines with trans/cis diastereomeric ratios ranging typically from 3:1 to 6:1. Cyclization with tris( trimethylsilyl)silane affords the same products with diastereomeric ratios of up to 99: 1 in certain cases. The enhancement in diastereoselectivity results from the selective rearrangement of the minor stereoisomer through a cascade process involving radical cyclization to the piperidine radical, 1,5-radical translocation, and attack of the translocated radical onto the sulfonamide with extrusion of SO2 in a Smiles-type rearrangement. Slower trapping of the piperidine radical by tris(trimethylsilyl) silane compared to tributyltin hydride accounts for the occurrence of the rearrangement cascade in the former case.

  DOI：

  10.1021/jo060495w
• 作为产物：
  描述：

  L-亮氨醇 在 咪唑 、 4-二甲氨基吡啶 、 caesium carbonate 、 三乙胺 作用下， 以 二氯甲烷 、 N,N-二甲基甲酰胺 、 乙腈 为溶剂， 反应 144.0h， 生成 (S)-4-aza-5-iso-butyl-6-(tert-butyldimethylsilanyloxy)-4-(p-toluenesulfonyl)hexanal dimethyl acetal
  参考文献：
  名称：

  Synthesis of 2,4-Disubstituted Piperidines via Radical Cyclization:  Unexpected Enhancement in Diastereoselectivity with Tris(trimethylsilyl)silane

  摘要：

  [GRAPHICS]A novel approach to 2,4-disubstituted piperidines is reported, involving the radical cyclization of 7-substituted-6-aza-8-bromooct-2-enoates. Cyclization with tributyltin hydride affords the trans piperidines with trans/cis diastereomeric ratios ranging typically from 3:1 to 6:1. Cyclization with tris( trimethylsilyl)silane affords the same products with diastereomeric ratios of up to 99: 1 in certain cases. The enhancement in diastereoselectivity results from the selective rearrangement of the minor stereoisomer through a cascade process involving radical cyclization to the piperidine radical, 1,5-radical translocation, and attack of the translocated radical onto the sulfonamide with extrusion of SO2 in a Smiles-type rearrangement. Slower trapping of the piperidine radical by tris(trimethylsilyl) silane compared to tributyltin hydride accounts for the occurrence of the rearrangement cascade in the former case.

  DOI：

  10.1021/jo060495w