(2S,4S,5S)-5-<(tert-Butyldiphenylsilyl)oxy>-7-dibromo-2,4-dimethyl-6-heptenal | 147121-99-1

• 分子结构分类: 有机化合物 - 有机金属化合物 - 有机类金属化合物
• 英文名称: (2S,4S,5S)-5-<(tert-Butyldiphenylsilyl)oxy>-7-dibromo-2,4-dimethyl-6-heptenal
• 英文别名: (2S,4S,5S)-7,7-dibromo-5-[tert-butyl(diphenyl)silyl]oxy-2,4-dimethylhept-6-enal
• CAS: 147121-99-1
• 化学式: C₂₅H₃₂Br₂O₂Si
• 分子量: 552.421
• InChiKey: GOHYSFIGZBNHPP-SXWKCWPCSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.42
• 重原子数：
  30
• 可旋转键数：
  10
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.4
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (2S,4S,5S)-5-<(tert-Butyldiphenylsilyl)oxy>-7-dibromo-2,4-dimethyl-6-heptenal 在 4 A molecular sieve 、 四丙基氢氧化铵 、 lithium hexamethyldisilazane 作用下， 以 xylene 为溶剂， 反应 3.17h， 生成 (5S,6R,9R)-6-[(E)-3-[tert-butyl(dimethyl)silyl]oxy-2-methylprop-1-enyl]-8-[[tert-butyl(diphenyl)silyl]oxymethyl]-3-[(2E,4S,6S,7S)-9,9-dibromo-7-[tert-butyl(diphenyl)silyl]oxy-2,4,6-trimethylnona-2,8-dienoyl]-4-methoxy-9-methyl-1-oxaspiro[4.5]deca-3,7-dien-2-one
  参考文献：
  名称：

  Studies on the synthesis of kijanolide: synthesis of the 2-acyl spirotetronate and investigations concerning the coupling of the top and bottom half fragments

  摘要：

  Several studies directed toward the synthesis of kijanolide are described. First, a method for synthesis of the 2-acyl spiro tetronate substructure (15,52) via a Dieckmann cyclization protocol was developed. Second, a 10-step synthesis of 7,7-dibromo-2,4-dimethyl-5-[(tert-butyldiphenylsilyl)oxy]heptenal 35 was developed, making possible the synthesis of a range of kijanolide bottom half precursors via olefination (e.g., 35 + 23 --> 38) and cross-coupling reactions (e.g., 38 --> 19). This solves the problems encountered due to the introduction of the C(7)-hydroxyl group in our previous synthesis of the kijanolide bottom half 2.2a Third, a highly efficient procedure was developed for the coupling of kijanolide top half 8 and dioxinone 38 via an acyl ketene intermediate. This is the most efficient of several methods examined for acylating the hindered tertiary hydroxyl group of 8. Attempts to perform the IMDA reaction of 46, 47 or 9 (R = SiEt3) generated in situ from coupling of 8 and the acyl ketene (20) derived from 42 were thwarted by the unexpected tendency of beta-keto esters like 47 to fragment and decarboxylate via the acyl ketene intermediate at temperatures above 115-degrees-C. 2-Acyl tetronates 53 and 54 were prepared, but these systems decomposed upon attempted IMDA cyclization at temperatures approaching 190-degrees-C.

  DOI：

  10.1021/jo00060a036
• 作为产物：
  描述：

  (2'S,4S,4'S,5'S,6'R)-3-<5'-<(tert-Butyldiphenylsilyl)oxy>-2',4'-dimethyl-6',7'-O-isopropylideneheptanoyl>-4-isopropyl-1,3-oxazolidin-2-one 在 sodium periodate 、 二异丁基氢化铝 、 溶剂黄146 、 三苯基膦 作用下， 以 四氢呋喃 、 二氯甲烷 、 水 为溶剂， 反应 35.5h， 生成 (2S,4S,5S)-5-<(tert-Butyldiphenylsilyl)oxy>-7-dibromo-2,4-dimethyl-6-heptenal
  参考文献：
  名称：

  Studies on the synthesis of kijanolide: synthesis of the 2-acyl spirotetronate and investigations concerning the coupling of the top and bottom half fragments

  摘要：

  Several studies directed toward the synthesis of kijanolide are described. First, a method for synthesis of the 2-acyl spiro tetronate substructure (15,52) via a Dieckmann cyclization protocol was developed. Second, a 10-step synthesis of 7,7-dibromo-2,4-dimethyl-5-[(tert-butyldiphenylsilyl)oxy]heptenal 35 was developed, making possible the synthesis of a range of kijanolide bottom half precursors via olefination (e.g., 35 + 23 --> 38) and cross-coupling reactions (e.g., 38 --> 19). This solves the problems encountered due to the introduction of the C(7)-hydroxyl group in our previous synthesis of the kijanolide bottom half 2.2a Third, a highly efficient procedure was developed for the coupling of kijanolide top half 8 and dioxinone 38 via an acyl ketene intermediate. This is the most efficient of several methods examined for acylating the hindered tertiary hydroxyl group of 8. Attempts to perform the IMDA reaction of 46, 47 or 9 (R = SiEt3) generated in situ from coupling of 8 and the acyl ketene (20) derived from 42 were thwarted by the unexpected tendency of beta-keto esters like 47 to fragment and decarboxylate via the acyl ketene intermediate at temperatures above 115-degrees-C. 2-Acyl tetronates 53 and 54 were prepared, but these systems decomposed upon attempted IMDA cyclization at temperatures approaching 190-degrees-C.

  DOI：

  10.1021/jo00060a036

文献信息

• Studies on the synthesis of kijanolide: synthesis of the 2-acyl spirotetronate and investigations concerning the coupling of the top and bottom half fragments
  作者：William R. Roush、Bradley B. Brown

  DOI：10.1021/jo00060a036

  日期：1993.4

  Several studies directed toward the synthesis of kijanolide are described. First, a method for synthesis of the 2-acyl spiro tetronate substructure (15,52) via a Dieckmann cyclization protocol was developed. Second, a 10-step synthesis of 7,7-dibromo-2,4-dimethyl-5-[(tert-butyldiphenylsilyl)oxy]heptenal 35 was developed, making possible the synthesis of a range of kijanolide bottom half precursors via olefination (e.g., 35 + 23 --> 38) and cross-coupling reactions (e.g., 38 --> 19). This solves the problems encountered due to the introduction of the C(7)-hydroxyl group in our previous synthesis of the kijanolide bottom half 2.2a Third, a highly efficient procedure was developed for the coupling of kijanolide top half 8 and dioxinone 38 via an acyl ketene intermediate. This is the most efficient of several methods examined for acylating the hindered tertiary hydroxyl group of 8. Attempts to perform the IMDA reaction of 46, 47 or 9 (R = SiEt3) generated in situ from coupling of 8 and the acyl ketene (20) derived from 42 were thwarted by the unexpected tendency of beta-keto esters like 47 to fragment and decarboxylate via the acyl ketene intermediate at temperatures above 115-degrees-C. 2-Acyl tetronates 53 and 54 were prepared, but these systems decomposed upon attempted IMDA cyclization at temperatures approaching 190-degrees-C.