(+/-)-1-(tert-butyl)-4,4-dimethyl-1-[(trimethylsilyl)ethynyl]pent-2-ynyl methyl carbonate | 503569-95-7

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 有机碳酸及其衍生物
• 英文名称: (+/-)-1-(tert-butyl)-4,4-dimethyl-1-[(trimethylsilyl)ethynyl]pent-2-ynyl methyl carbonate
• CAS: 503569-95-7
• 化学式: C₁₈H₃₀O₃Si
• 分子量: 322.52
• InChiKey: VMVPMCLADQADLU-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.48
• 重原子数：
  22.0
• 可旋转键数：
  1.0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.72
• 拓扑面积：
  35.53
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  (+/-)-1-(tert-butyl)-4,4-dimethyl-1-[(trimethylsilyl)ethynyl]pent-2-ynyl methyl carbonate 、 三甲基乙炔基硅 在 copper(l) iodide 、 四(三苯基膦)钯 二异丙胺 作用下， 以 1,2-二氯乙烷 为溶剂， 反应 1.0h， 生成 (+/-)-3,5-di(tert-butyl)-1,7-bis(trimethylsilyl)hepta-3,4-diene-1,6-diyne 、 (+/-)-5-(tert-butyl)-8,8-dimethyl-1,3-bis(trimethylsilyl)nona-3,4-diene-1,6-diyne
  参考文献：
  名称：

  1,3-Diethynylallenes: Carbon-Rich Modules for Three-Dimensional Acetylenic Scaffolding

  摘要：

  Regioselective Pd-0-catalyzed cross-coupling of substrates, which bear bispropargylic leaving groups with silyl-protected alkynes, has provided access to a variety of 1.3-diethynylailenes, a new family of modules for three-dimensional acetylenic scaffolding. In enantiomerically pure form, these C-rich building blocks could provide access - by oxidative oligomerization - to a fascinating new class of helical oligomers and polymers with all-carbon backbones (Fig. 2). In the first of two routes. a bispropargylic epoxide underwent ring opening during S(N)2'-type cross-coupling. and the resulting alkoxide was silyl-protected, providing 1,3-diethynylailenes (+/-)-8, (+/-)-12 (Scheme 3), and (+/-)-15 (Scheme 5). A more general approach involved bispropargylic carbonates or esters as substrates (Scheme 6-8), and this route was applied to the preparation of a series of 13-diethyrrylallenes to investigate how their overall stability against undesirable [2 + 2] cycloaddition is affected by the nature of the substituents at the allene moiety. The investigation showed that the 1,3-diethynylallene chromophore is stable against [2 + 2] cycloaddition only when protected by steric bulk and when additional relectron delocalization is avoided. The regioselectivity of the cross-coupling to the bispropargylic substrates is entirely controlled by steric factors: attack occurs at the alkyne moiety bearing the smaller substituent (Schemes 9 and 10). Oxidative Hay coupling of the terminally mono-deprotected 1.3-diethynylallene (+/-)-49 afforded the first dimer 50, probably as a mixture of two diastereoisomers (Scheme 12). Attempts to prepare a silyl-protected tetraethynylallene by the new methodology failed (Scheme 13). Control experiments (Schemes 14 - 16) showed that the Pd-0-catalyzed cross-coupling to butadiyne moieties in the synthesis of this still-elusive chromophore requires forcing conditions under which rapid [2 + 2] cycloaddition of the initial product cannot be avoided.

  DOI：

  10.1002/1522-2675(200210)85:10<3052::aid-hlca3052>3.0.co;2-4
• 作为产物：
  描述：

  2,2,6,6-tetramethylhepta-4-yn-3-one 在 正丁基锂 、 lithium hexamethyldisilazane 作用下， 以 四氢呋喃 、 正己烷 为溶剂， 反应 1.25h， 生成 (+/-)-1-(tert-butyl)-4,4-dimethyl-1-[(trimethylsilyl)ethynyl]pent-2-ynyl methyl carbonate
  参考文献：
  名称：

  1,3-Diethynylallenes: Carbon-Rich Modules for Three-Dimensional Acetylenic Scaffolding

  摘要：

  Regioselective Pd-0-catalyzed cross-coupling of substrates, which bear bispropargylic leaving groups with silyl-protected alkynes, has provided access to a variety of 1.3-diethynylailenes, a new family of modules for three-dimensional acetylenic scaffolding. In enantiomerically pure form, these C-rich building blocks could provide access - by oxidative oligomerization - to a fascinating new class of helical oligomers and polymers with all-carbon backbones (Fig. 2). In the first of two routes. a bispropargylic epoxide underwent ring opening during S(N)2'-type cross-coupling. and the resulting alkoxide was silyl-protected, providing 1,3-diethynylailenes (+/-)-8, (+/-)-12 (Scheme 3), and (+/-)-15 (Scheme 5). A more general approach involved bispropargylic carbonates or esters as substrates (Scheme 6-8), and this route was applied to the preparation of a series of 13-diethyrrylallenes to investigate how their overall stability against undesirable [2 + 2] cycloaddition is affected by the nature of the substituents at the allene moiety. The investigation showed that the 1,3-diethynylallene chromophore is stable against [2 + 2] cycloaddition only when protected by steric bulk and when additional relectron delocalization is avoided. The regioselectivity of the cross-coupling to the bispropargylic substrates is entirely controlled by steric factors: attack occurs at the alkyne moiety bearing the smaller substituent (Schemes 9 and 10). Oxidative Hay coupling of the terminally mono-deprotected 1.3-diethynylallene (+/-)-49 afforded the first dimer 50, probably as a mixture of two diastereoisomers (Scheme 12). Attempts to prepare a silyl-protected tetraethynylallene by the new methodology failed (Scheme 13). Control experiments (Schemes 14 - 16) showed that the Pd-0-catalyzed cross-coupling to butadiyne moieties in the synthesis of this still-elusive chromophore requires forcing conditions under which rapid [2 + 2] cycloaddition of the initial product cannot be avoided.

  DOI：

  10.1002/1522-2675(200210)85:10<3052::aid-hlca3052>3.0.co;2-4