(2R,4R)-4-(tert-butoxycarbonylmethyl)-2-isopropyl-1-(p-toluenesulfonyl)-piperidine | 767288-32-4

• 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: (2R,4R)-4-(tert-butoxycarbonylmethyl)-2-isopropyl-1-(p-toluenesulfonyl)-piperidine
• 英文别名: tert-butyl 2-[(2R,4R)-1-(4-methylphenyl)sulfonyl-2-propan-2-ylpiperidin-4-yl]acetate
• CAS: 767288-32-4
• 化学式: C₂₁H₃₃NO₄S
• 分子量: 395.563
• InChiKey: SDMLCPXWINCKNY-IEBWSBKVSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.4
• 重原子数：
  27
• 可旋转键数：
  7
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  72.1
• 氢给体数：
  0
• 氢受体数：
  5

反应信息

• 作为反应物：
  描述：

  (2R,4R)-4-(tert-butoxycarbonylmethyl)-2-isopropyl-1-(p-toluenesulfonyl)-piperidine 在 氢溴酸 、 溶剂黄146 、 苯酚 作用下， 反应 96.0h， 以60 mg的产率得到((2R,4R)-2-Isopropyl-piperidin-4-yl)-acetic acid; hydrobromide
  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：

  (E)-5-[((S)-1-Methanesulfonyloxymethyl-2-methyl-propyl)-(toluene-4-sulfonyl)-amino]-pent-2-enoic acid tert-butyl ester 在 偶氮二异丁腈 、 三正丁基氢锡 、 lithium bromide 作用下， 以 四氢呋喃 为溶剂， 反应 48.0h， 生成 (2R,4R)-4-(tert-butoxycarbonylmethyl)-2-isopropyl-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

文献信息

• Tris(trimethylsilyl)silane: an unprecedented enhancement in the diastereoselectivity of radical cyclisations to give 2,4-disubstituted piperidines
  作者：Lucile A. Gandon、Alexander G. Russell、John S. Snaith

  DOI：10.1039/b409714a

  日期：——

  Cyclisation of bromides 4a–f mediated by tributyltin hydride affords predominantly the trans piperidines 5a–f with modest diastereomeric ratios, while cyclisation with tris(trimethylsilyl)silane affords the same products with diastereomeric ratios of up to 99 : 1.

  由三丁基锡氢化物介导的溴化物4a–f的环化主要生成反式哌啶5a–f，具有适中的非对映体比，而与三（甲基硅基）硅烷的环化则生成相同的产物，非对映体比高达99 : 1。
• Synthesis of 2,4-Disubstituted Piperidines via Radical Cyclization:  Unexpected Enhancement in Diastereoselectivity with Tris(trimethylsilyl)silane
  作者：Lucile A. Gandon、Alexander G. Russell、Tatyana Güveli、Angela E. Brodwolf、Benson M. Kariuki、Neil Spencer、John S. Snaith

  DOI：10.1021/jo060495w

  日期：2006.7.1

  [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.