(Z)-1-bromo-4-cyclohexylidene-1,3-butadiene

• 分子结构分类: 有机化合物 - 有机卤素化合物 - 乙烯基卤化物
• 英文名称: (Z)-1-bromo-4-cyclohexylidene-1,3-butadiene
• 英文别名: [(Z)-3-bromoprop-2-enylidene]cyclohexane
• 化学式: C₉H₁₃Br
• 分子量: 201.106
• InChiKey: DZXBBTPRBXAINW-YWEYNIOJSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.6
• 重原子数：
  10
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.56
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为产物：
  描述：

  (3,3-Dibromo-allylidene)-cyclohexane 在 四(三苯基膦)钯 、 三正丁基氢锡 作用下， 反应 0.8h， 以90%的产率得到(Z)-1-bromo-4-cyclohexylidene-1,3-butadiene
  参考文献：
  名称：

  Stereoselective Hydrogenolysis of 1,1-Dibromo-1-alkenes and Stereospecific Synthesis of Conjugated (Z)-Alkenyl Compounds

  摘要：

  The Pd-catalyzed hydrogenolysis of 1,1-dibromoalkenes with Bu3SnH occurs at room temperature stereoselectively to give (Z)-1-bromo-1-alkenes. We sought to determine the optimal reaction conditions and illustrate the scope of this method with 32 dibromoalkenes including alkenyl- and alkynyl-conjugated 1,l-dibromo-l-alkenes 7a-h and 2,2-disubstituted I,1-dibromo-1-alkenes 9a-f. Triphenylphosphine was the best ligand for the Pd-catalyzed hydrogenolysis. A wide range of solvents can be used for this reaction excluding EtOH, AcOH, and CHCl3. However, the reaction proceeds even in these solvents with the addition of a cosolvent or radical scavenger. The reaction of 1,1-diiodo-1-alkene (3) gave a mixture of (Z)-1-iodo-1-alkene (4), (Z)-1-tributylstannyl-1-alkene (5), and a terminal alkene 6, while that of 1,1-dichloroalkene did not occur. This selectivity can be explained by the stereoselective insertion of Pd(0) to a trans bromine-alkenyl carbon bond, successive transmetalation with Bu3SnH, and reductive elimination. The Suzuki and Sonogashira couplings of the resulting (Z)-1-bromo-1-alkenes with alkenyl(dialkoxy)borane and terminal alkyne occurred to give conjugated polyenes and enynes stereospecifically. The Pd-catalyzed hydrogenolysis of 1,l-dibromo-l-alkene and successive cross-coupling can be carried out either in a stepwise manner or in one-pot under the same Pd catalysis. These two processes should be useful for the synthesis of geometrically pure polyene and enyne with a Z-alkenyl unit.

  DOI：

  10.1021/jo9812781

文献信息

• Simple and selective method for aldehydes (RCHO) .fwdarw. (E)-haloalkenes (RCH:CHX) conversion by means of a haloform-chromous chloride system
  作者：K. Takai、K. Nitta、K. Utimoto

  DOI：10.1021/ja00283a046

  日期：1986.11
• Stereoselective Hydrogenolysis of 1,1-Dibromo-1-alkenes and Stereospecific Synthesis of Conjugated (<i>Z</i>)-Alkenyl Compounds
  作者：Jun'ichi Uenishi、Reiko Kawahama、Osamu Yonemitsu、Jiro Tsuji

  DOI：10.1021/jo9812781

  日期：1998.11.1

  The Pd-catalyzed hydrogenolysis of 1,1-dibromoalkenes with Bu3SnH occurs at room temperature stereoselectively to give (Z)-1-bromo-1-alkenes. We sought to determine the optimal reaction conditions and illustrate the scope of this method with 32 dibromoalkenes including alkenyl- and alkynyl-conjugated 1,l-dibromo-l-alkenes 7a-h and 2,2-disubstituted I,1-dibromo-1-alkenes 9a-f. Triphenylphosphine was the best ligand for the Pd-catalyzed hydrogenolysis. A wide range of solvents can be used for this reaction excluding EtOH, AcOH, and CHCl3. However, the reaction proceeds even in these solvents with the addition of a cosolvent or radical scavenger. The reaction of 1,1-diiodo-1-alkene (3) gave a mixture of (Z)-1-iodo-1-alkene (4), (Z)-1-tributylstannyl-1-alkene (5), and a terminal alkene 6, while that of 1,1-dichloroalkene did not occur. This selectivity can be explained by the stereoselective insertion of Pd(0) to a trans bromine-alkenyl carbon bond, successive transmetalation with Bu3SnH, and reductive elimination. The Suzuki and Sonogashira couplings of the resulting (Z)-1-bromo-1-alkenes with alkenyl(dialkoxy)borane and terminal alkyne occurred to give conjugated polyenes and enynes stereospecifically. The Pd-catalyzed hydrogenolysis of 1,l-dibromo-l-alkene and successive cross-coupling can be carried out either in a stepwise manner or in one-pot under the same Pd catalysis. These two processes should be useful for the synthesis of geometrically pure polyene and enyne with a Z-alkenyl unit.