2-methylbenzaldehyde | 138151-99-2

• 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: 2-methylbenzaldehyde
• 英文别名: -o-tolualdehyde；[carbonyl-13C] o-tolualdehyde；o-Methyl-benzaldehyd-7-¹³C；2-methyl-[α-¹³C]benzaldehyde；o-Tolualdehyde-13C1 (carbonyl-13C)；2-methylbenzaldehyde
• CAS: 138151-99-2
• 化学式: C₈H₈O
• 分子量: 121.14
• InChiKey: BTFQKIATRPGRBS-PTQBSOBMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.81
• 重原子数：
  9.0
• 可旋转键数：
  1.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.12
• 拓扑面积：
  17.07
• 氢给体数：
  0.0
• 氢受体数：
  1.0

反应信息

• 作为反应物：
  描述：

  2-methylbenzaldehyde 在 四氯化钛 、 锌 作用下， 以 四氢呋喃 为溶剂， 反应 17.0h， 生成 (E)-2,2-dimethyl<α,β-13C2>stilbene
  参考文献：
  名称：

  Molecular structure and intramolecular motion of (E)-stilbenes in crystals. An interpretation of the unusually short ethylene bond

  摘要：

  Crystal structures of (E)-2,2'-dimethylstilbene (2), (E)-2,2',4,4'-tetramethylstilbene (3), (E)-2,2',5,5'-tetramethylstilbene (4), (E)-2,2',4,4',5,5'-hexamethylstilbene (5), and (E)-2,2',3,3-tetramethylstilbene (6) were determined at several temperatures by X-ray diffraction. Analyses of these results and also of those reported for (E)-stilbene (1) and its related compounds revealed that the X-ray structures of compounds having the (E)-stilbene skeleton commonly show an unusually short bond length for the ethylene bond and a strong temperature dependence for the molecular structure. No sign confirming these anomalies could be detected in solution by NMR or UV spectroscopy. It is concluded that the short ethylene bond in the X-ray structures of these compounds is an artifact caused by dynamic averaging originating from the torsional vibration of the C-Ph bonds, during which the movement of the benzene rings is restrained to be a minimum. The observed temperature dependence of the ethylene bond length and angles and of the torsion angles of the C-Ph bonds is ascribed to the slight energy difference between the conformers, which interconvert by the torsional vibration. It has also been revealed that the rotational vibration of the benzene rings around the normal axes through C1 and C1' is a characteristic motion of (E)-stilbenes in the crystalline state.

  DOI：

  10.1021/ja00029a037
• 作为产物：
  描述：

  -o-toluic acid 在 lithium aluminium tetrahydride 、 ammonium cerium(IV) nitrate 作用下， 以 乙醚 、 水 为溶剂， 生成 2-methylbenzaldehyde
  参考文献：
  名称：

  Thermal isomerization of benzocyclobutene

  摘要：

  DOI：

  10.1021/ja00236a038

文献信息

• The Elusive Benzocyclobutenylidene:  A Combined Computational and Experimental Attempt
  作者：Athanassios Nicolaides、Takeshi Matsushita、Kohichi Yonezawa、Shinji Sawai、Hideo Tomioka、Louise L. Stracener、Jonathan A. Hodges、Robert J. McMahon

  DOI：10.1021/ja0039482

  日期：2001.3.1

  Ab initio and density functional theory calculations predict that benzocyclobutenylidene (1) has a singlet ground state in contrast to the parent phenylcarbene and many other simply substituted arylcarbenes. Calculations also predict that 1 should lie in a relatively deep potential well, while its tripler state is 14.5 kcal mol(-1) higher in energy. However,:attempts to observe 1 directly by photolysis of two different nitrogenous precursors were not successful. Irradiation of diazobenzocyclobutene (7) (lambda > 534 nm or lambda > 300 nm) or azibenzocycllobutene (10) (lambda > 328 nm) in Ar matrixes at 10 K leads to the formation of the strained cycloalkyne 7-methylenecyclohepta-3,5-dien-1-yne (3). C-13-Labeled 3 was also prepared in a similar manner. There is very good agreement between experimental IR spectra and computationally derived harmonic vibrational frequencies for 3 and [C-13]-3 and excellent agreement between observed and calculated isotopic shifts. Prolonged short-wavelength irradiation converts 3 into benzocyclobutadiene (5). Phenylacetylene (6) and benzocyclo- butadiene dimer (11) were identified as products arising from flash vacuum pyrolysis of diazirine 10 at 500 degreesC.
• Gold-Catalyzed 1,3-Transposition of Ynones
  作者：Roohollah Kazem Shiroodi、Mohammad Soltani、Vladimir Gevorgyan

  DOI：10.1021/ja504892c

  日期：2014.7.16

  An efficient, regioselective gold-catalyzed 1,3-transposition reaction of ynones and diynones has been developed. It was found that stereoelectronic (interrupted conjugation) and electronic (extended conjugation) factors could efficiently govern the regioselectivity of this thermodynamically controlled transformation. The produced conjugated diynones were efficiently transformed into diverse alkyne-substituted five- and six-membered heterocycles.