trans-2-Chloro-1,1,3-trimethylcyclopentane

• 分子结构分类: 有机化合物 - 有机卤素化合物 - 有机氯化物
• 英文名称: trans-2-Chloro-1,1,3-trimethylcyclopentane
• 英文别名: (2R,3S)-2-chloro-1,1,3-trimethylcyclopentane
• 化学式: C₈H₁₅Cl
• 分子量: 146.66
• InChiKey: QBMZOQVOXARFEH-NKWVEPMBSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.4
• 重原子数：
  9
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  1.0
• 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：

  2,2-二甲基-5-己烯-1-醇 在 五氯化磷 、 magnesium 、 pyridinium chlorochromate 作用下， 以 四氢呋喃 、 正己烷 、 二氯甲烷 为溶剂， 反应 34.0h， 生成 trans-2-Chloro-1,1,3-trimethylcyclopentane
  参考文献：
  名称：

  Mechanism of Reaction of Geminal Dihalides with Magnesium. Evidence for the Formation of Carbenes from Radical Precursors. The Similarity in Reactions of Geminal Dihalides with Magnesium and LiAlH4

  摘要：

  Two geminal dihalides, 6,6-dichloro-5,5-dimethyl-1-hexene (2a) and 6,6-diiodo-5,5-dimethyl-1-hexene (2b) were allowed to react with Rieke activated magnesium (Mg*) in THF at 25 degrees C. Both radical and carbene intermediates were identified by product analyses, by radical trapping experiments using DCPH and THF-d(8), and by selective experiments in which isolated intermediates were shown to form the predicted products. Although carbene products predominated over radical products when the dichloride was allowed to react with Mg*, radical products predominated when the diiodide was allowed to react with Mg*. Evidence is presented that indicates that the carbene intermediate arises from a radical precursor. A mechanistic scheme (Scheme 5) is presented that is consistent with all of the observed data. A comparison of the reactions of 2b with Mg* and 2b with LiAlH4 shows that most of the products are common in both reactions thereby providing further evidence for LiAlH4 as a one-electron donor, as is the known behavior of Mg*.

  DOI：

  10.1021/jo00100a024

文献信息

• Electron Transfer in the Reactions of Geminal Dihalides with Ph2P-. Evidence for the Formation of a Carbene Intermediate from a Radical Precursor
  作者：E. C. Ashby、Abhay K. Deshpande

  DOI：10.1021/jo00127a014

  日期：1995.11

  The reactions of two sterically hindered geminal dihalides, 6,6-dichloro-5,5-dimethyl-1-hexene (5a) and 6,6-diiodo-5,5-dimethyl-1-hexene (5b), with Ph(2)P(-) have been found to involve a single electron transfer (SET) pathway. Since the corresponding monochloride reacts with Ph(2)P(-) by a S(N)2 pathway, it is clear that adding a second chlorine atom on a carbon atom produces a more favorable reduction potential resulting in a change in mechanism from S(N)2 to SET. Evidence is also presented that shows that the geminal dihalides produce carbene-derived products and that the carbene was derived from a haloalkyl radical precursor.
• Mechanism of Reaction of Geminal Dihalides with Lithium Aluminum Hydride. Evidence for Single Electron Transfer as the Major Reaction Pathway
  作者：E. C. Ashby、Abhay K. Deshpande

  DOI：10.1021/jo00093a011

  日期：1994.7

  The reactions of a sterically hindered geminal dichloride 4a and the corresponding diiodide 4b with LiAlH4 (LAH) were found to involve an electron-transfer mechanism. Whereas the monochloro analog of 4a (8) is inert toward LAH, 4a was more reactive. Observation of radical-derived products in the reaction of 4a with LAH indicates that the presence of two chlorine atoms on the same carbon atom results in a favorable reduction potential for 4a, as compared to 8. These results show that LAH can function as a one-electron donor toward geminal dichlorides. It was found that the diiodo analog 4b is more reactive toward LAH than 4a due to the inherent favorable reduction potentials of alkyl iodides compared to chlorides. The reactivity of 4b toward LAH was also found to be greater than that of the monoiodo analog (Ib) in keeping with the more favorable reduction potential of the diiodide (4b) compared to the monoiodide (Ib). The rates of cyclization of the corresponding haloalkyl radicals generated from 4a and 4b were also determined and were found to be 7.4 x 10(5)/s for the chloroalkyl and 5.5 x 10(5)/s for the iodoalkyl radical at 25 degrees C. The formation of small amounts of the carbene-derived product, 5, in the reactions of both 4a and 4b with LAH appeared to be preceded by a radical intermediate.
• Mechanism of Reaction of Geminal Dihalides with Lithium Naphthalenide (LiNp.bul.-): Evidence for an Electron Transfer Mechanism. Similarities to the Mechanism of Reaction of Geminal Dihalides with Certain Nucleophiles and Other One-Electron Donors
  作者：E. C. Ashby、Abhay K. Deshpande

  DOI：10.1021/jo00119a034

  日期：1995.7

  The reactions of the sterically hindered geminal dihalides 6,6-dichloro-5,5-dimethyl-1-hexene (1a) and 6,6-diiodo-5,5-dimethyl-1-hexene (1b) with lithium naphthalenide (LiNp.-) in THF were investigated in an attempt to compare the results of reactions involving a known one-electron donor (LiN.- -) with those involving nucleophiles believed to be one-electron donors. On the basis of radical-trapping studies, deuterium tracer studies, and product studies using cyclizable radical probes, it can be concluded that the reactions studied are very similar to those reported by us earlier involving magnesium metal, LiAlH4, and other nucleophiles. In addition to radical-derived products, the reaction of 1a with LiNp.- afforded hydrocarbons, in high yields, that were derived from a carbene intermediate. On the other hand, 1b, on reaction with LiNp.-, did not yield any carbene-derived hydrocarbons. These results show that the formation of a carbene intermediate, derived from a radical, depends on the nature of the halogen present. It was also found that naphthalene can behave as a hydrogen atom donor toward a radical in the presence of known hydrogen atom donors, such as THF.
• The Mechanism of Reaction of Geminal Dihalides with Sodium Trimethyltin. Evidence for a Single Electron Transfer Initiated Reaction Which Produces Both Radical and Carbene Intermediates
  作者：E. C. Ashby、Abhay K. Deshpande

  DOI：10.1021/jo00103a030

  日期：1994.12

  The reactions of two geminal dihalides, 6,6-dichloro-5,5-dimethyl-1-hexene (2a) and 6,6-diiodo-5,5-dimethyl-1-hexene (2b) with sodium trimethyltin (NaSnMe(3)), a known one-electron donor toward alkyl halides, have been studied. Evidence for a single electron transfer (SET) pathway has been obtained for both reactions. Although the monochloro analog of 2a, namely 7, was inert toward NaSnMe(3), 2a afforded 11 products. The nature of the products clearly indicates that the presence of two chlorine atoms on the same carbon atom results in a more favorable reduction potential than when just one chlorine atom is present. Both 2a and 2b on reaction with NaSnMe(3) also produced carbene-derived products, and evidence is presented that establishes that the carbene intermediate was in fact preceded by a radical intermediate. In addition, trimethyltin-substituted products (open chain as well as cyclized) were also obtained from both substrates and were found. to be derived from radical intermediates.
• Mechanism of Reaction of Geminal Dihalides with Magnesium. Evidence for the Formation of Carbenes from Radical Precursors. The Similarity in Reactions of Geminal Dihalides with Magnesium and LiAlH4
  作者：E. C. Ashby、Abhay K. Deshpande、Fabio Doctorovich

  DOI：10.1021/jo00100a024

  日期：1994.10

  Two geminal dihalides, 6,6-dichloro-5,5-dimethyl-1-hexene (2a) and 6,6-diiodo-5,5-dimethyl-1-hexene (2b) were allowed to react with Rieke activated magnesium (Mg*) in THF at 25 degrees C. Both radical and carbene intermediates were identified by product analyses, by radical trapping experiments using DCPH and THF-d(8), and by selective experiments in which isolated intermediates were shown to form the predicted products. Although carbene products predominated over radical products when the dichloride was allowed to react with Mg*, radical products predominated when the diiodide was allowed to react with Mg*. Evidence is presented that indicates that the carbene intermediate arises from a radical precursor. A mechanistic scheme (Scheme 5) is presented that is consistent with all of the observed data. A comparison of the reactions of 2b with Mg* and 2b with LiAlH4 shows that most of the products are common in both reactions thereby providing further evidence for LiAlH4 as a one-electron donor, as is the known behavior of Mg*.