2,4-pentadiynal | 882045-04-7

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 2,4-pentadiynal
• 英文别名: Pent-2,4-diyne-1-al；penta-2,4-diynal
• CAS: 882045-04-7
• 化学式: C₅H₂O
• 分子量: 78.0703
• InChiKey: MHIQSTHHVCANOT-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.6
• 重原子数：
  6
• 可旋转键数：
  1
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  17.1
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  2,4-pentadiynal 在 sodium hydride 作用下， 以 乙醚 、 二氯甲烷 为溶剂， 反应 25.0h， 生成 1-diazo-2,4-pentadiyne
  参考文献：
  名称：

  Reactive Carbon-Chain Molecules:  Synthesis of 1-Diazo-2,4-pentadiyne and Spectroscopic Characterization of Triplet Pentadiynylidene (H−C⋮C−C̈−C⋮C−H)

  摘要：

  1-Diazo-2,4-pentadiyne (6a), along with both monodeuterio isotopomers; 6b and 6c, has been synthesized via a route that proceeds through diacetylene, 2,4-pentadiynal, and 2,4-pentadiynal tosylhydrazone. Photolysis of diazo compounds 6a-c (lambda > 444 nm; Ar or N-2, 10 K) generates triplet carbenes HC5H (1) and HC5D (1-d), which have been characterized by IR, EPR, and UV/vis spectroscopy. Although many resonance structures contribute to the resonance hybrid for this highly unsaturated carbon-chain molecule, experiment and theory reveal that the structure is best depicted in terms of the dominant resonance contributor of penta-1,4-diyn-3-ylidene (diethynylcarbene, H-C equivalent to C-C-C equivalent to C-H). Theory predicts an axially symmetric (D-h) structure and a triplet electronic ground state for 1 (CCSD(T)/ANO). Experimental IR frequencies and isotope shifts are in good agreement with computed values. The triplet EPR spectrum of 1 (vertical bar D/hc vertical bar = 0.6157 cm(-1), vertical bar E/hc vertical bar = 0.0006 cm(-1)) is consistent with an axially symmetric structure, and the Curie law behavior confirms that the triplet state is the ground state. The electronic absorption spectrum of 1 exhibits a weak transition near 400 nm with extensive vibronic coupling. Chemical trapping of triplet HC5H (1) in an O-2-cloped matrix affords the carbonyl oxide 16 derived exclusively from attack at the central carbon.

  DOI：

  10.1021/ja058252t
• 作为产物：
  描述：

  2,4-pentadiyne-1-ol 在 戴斯-马丁氧化剂 作用下， 以 二氯甲烷 为溶剂， 反应 1.5h， 生成 2,4-pentadiynal
  参考文献：
  名称：

  Reactive Carbon-Chain Molecules:  Synthesis of 1-Diazo-2,4-pentadiyne and Spectroscopic Characterization of Triplet Pentadiynylidene (H−C⋮C−C̈−C⋮C−H)

  摘要：

  1-Diazo-2,4-pentadiyne (6a), along with both monodeuterio isotopomers; 6b and 6c, has been synthesized via a route that proceeds through diacetylene, 2,4-pentadiynal, and 2,4-pentadiynal tosylhydrazone. Photolysis of diazo compounds 6a-c (lambda > 444 nm; Ar or N-2, 10 K) generates triplet carbenes HC5H (1) and HC5D (1-d), which have been characterized by IR, EPR, and UV/vis spectroscopy. Although many resonance structures contribute to the resonance hybrid for this highly unsaturated carbon-chain molecule, experiment and theory reveal that the structure is best depicted in terms of the dominant resonance contributor of penta-1,4-diyn-3-ylidene (diethynylcarbene, H-C equivalent to C-C-C equivalent to C-H). Theory predicts an axially symmetric (D-h) structure and a triplet electronic ground state for 1 (CCSD(T)/ANO). Experimental IR frequencies and isotope shifts are in good agreement with computed values. The triplet EPR spectrum of 1 (vertical bar D/hc vertical bar = 0.6157 cm(-1), vertical bar E/hc vertical bar = 0.0006 cm(-1)) is consistent with an axially symmetric structure, and the Curie law behavior confirms that the triplet state is the ground state. The electronic absorption spectrum of 1 exhibits a weak transition near 400 nm with extensive vibronic coupling. Chemical trapping of triplet HC5H (1) in an O-2-cloped matrix affords the carbonyl oxide 16 derived exclusively from attack at the central carbon.

  DOI：

  10.1021/ja058252t

文献信息

• Reactive Carbon-Chain Molecules:  Synthesis of 1-Diazo-2,4-pentadiyne and Spectroscopic Characterization of Triplet Pentadiynylidene (H−C⋮C−C̈−C⋮C−H)
  作者：Nathan P. Bowling、Robert J. Halter、Jonathan A. Hodges、Randal A. Seburg、Phillip S. Thomas、Christopher S. Simmons、John F. Stanton、Robert J. McMahon

  DOI：10.1021/ja058252t

  日期：2006.3.1

  1-Diazo-2,4-pentadiyne (6a), along with both monodeuterio isotopomers; 6b and 6c, has been synthesized via a route that proceeds through diacetylene, 2,4-pentadiynal, and 2,4-pentadiynal tosylhydrazone. Photolysis of diazo compounds 6a-c (lambda > 444 nm; Ar or N-2, 10 K) generates triplet carbenes HC5H (1) and HC5D (1-d), which have been characterized by IR, EPR, and UV/vis spectroscopy. Although many resonance structures contribute to the resonance hybrid for this highly unsaturated carbon-chain molecule, experiment and theory reveal that the structure is best depicted in terms of the dominant resonance contributor of penta-1,4-diyn-3-ylidene (diethynylcarbene, H-C equivalent to C-C-C equivalent to C-H). Theory predicts an axially symmetric (D-h) structure and a triplet electronic ground state for 1 (CCSD(T)/ANO). Experimental IR frequencies and isotope shifts are in good agreement with computed values. The triplet EPR spectrum of 1 (vertical bar D/hc vertical bar = 0.6157 cm(-1), vertical bar E/hc vertical bar = 0.0006 cm(-1)) is consistent with an axially symmetric structure, and the Curie law behavior confirms that the triplet state is the ground state. The electronic absorption spectrum of 1 exhibits a weak transition near 400 nm with extensive vibronic coupling. Chemical trapping of triplet HC5H (1) in an O-2-cloped matrix affords the carbonyl oxide 16 derived exclusively from attack at the central carbon.