(4R,6R)-2-n-hexyl-4,6-dimethyl-1,3-dioxane | 93548-26-6

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 二恶烷
• 英文名称: (4R,6R)-2-n-hexyl-4,6-dimethyl-1,3-dioxane
• 英文别名: (4R,6R)-4,6-dimethyl-2-hexyl-1,3-dioxane；(4R,6R)-2-hexyl-4,6-dimethyl-1,3-dioxane
• CAS: 93548-26-6
• 化学式: C₁₂H₂₄O₂
• 分子量: 200.321
• InChiKey: BSNWHBPLTGXHBY-GHMZBOCLSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4
• 重原子数：
  14
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  18.5
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (4R,6R)-2-n-hexyl-4,6-dimethyl-1,3-dioxane 生成 (2R,4R)-4-(1-Ethyl-heptyloxy)-pentan-2-ol
  参考文献：
  名称：

  MORI, ATSUNORI;FUJIWARA, JUNYA;MARUOKA, KEIJI;YAMAMOTO, HISASHI, J. ORGANOMET. CHEM., 1985, 285, N 1-3, 83-94

  摘要：

  DOI：
• 作为产物：
  描述：

  庚醛 、 (2R,4R)-pentanediol 在 氢气 作用下， 生成 (4R,6R)-2-n-hexyl-4,6-dimethyl-1,3-dioxane
  参考文献：
  名称：

  使用有机钛试剂对乙缩醛进行亲核裂解。手性醇的新合成

  摘要：

  已经证明了用有机钛试剂对源自（-）-（2R，4R）-2,4-戊二醇的缩醛的高度化学和立体选择性裂解。反应在温和的条件下以优异的产率和高的化学选择性进行，在除去助剂后得到高对映体纯度的手性醇。另外，手性乙缩醛和TiCl 4的络合，然后用正丁基锂处理也导致形成具有高立体选择性的相应的丁基化醇。

  DOI：

  10.1016/s0040-4039(01)81455-6

文献信息

• Highly diastereoselective acetal cleavages using novel reagents prepared from organoaluminum and pentafluorophenol
  作者：Kazuaki Ishihara、Naoyuki Hanaki、Hisashi Yamamoto

  DOI：10.1021/ja00076a030

  日期：1993.11

  Chiral acetals derived from aldehydes and (-)-(2R,4R)-2,4-pentanediol are cleaved selectively by organoaluminum reagents. The reaction proceeds via the retentive-alkylation process with >95% selectivities in most cases. Trialkylaluminum reagent is utilized for higher alkyl transfers, but for smaller alkyl transfers, a new reagent system, combining trialkylaluminum and the halophenols such as pentafluorophenol

  衍生自醛和 (-)-(2R,4R)-2,4-戊二醇的手性缩醛被有机铝试剂选择性裂解。在大多数情况下，反应通过保留性烷基化过程进行，选择性大于 95%。三烷基铝试剂用于更高的烷基转移，但对于较小的烷基转移，采用了一种新的试剂系统，结合了三烷基铝和卤代酚，如五氟苯酚和 2,4,6-三氯苯酚。衍生自醛和 1,3-丁二醇的手性缩醛被三烷基铝选择性裂解，即使是较小的烷基转移也是如此。氧杂环丁烷也暴露在这些铝试剂中，立体选择性地获得了保留性烷基化产物
• Nucleophilic cleavage of acetals using organometallic reagents
  作者：Atsunori Mori、Junya Fujiwara、Keiji Maruoka、Hisashi Yamamoto

  DOI：10.1016/0022-328x(85)87359-9

  日期：1985.4

  A highly chemo- and stereo-selective cleavage of acetals derived from (−)(2R,4R)-2,4-pentanediol with organoaluminum and organotitanium reagents has been demonstrated. The reactions proceed under mild conditions with excellent yields and high chemoselectivities to give, after removal of the auxiliary, chiral alcohols of high enantiomeric purities.

  已经证明了用有机铝和有机钛试剂对源自（-）（2 R，4 R）-2,4-戊二醇的缩醛的高度化学和立体选择性裂解。反应在温和条件下以优异的收率和高化学选择性进行，在除去助剂后，得到高对映体纯度的手性醇。
• Stereoselective opening of chiral dioxane acetals. Nucleophile dependence
  作者：Scott E. Denmark、Neil G. Almstead

  DOI：10.1021/jo00023a002

  日期：1991.11

  The stereoselective allylation of chiral dioxane acetals 1 was found to be highly dependent on the nature of allymetal reagent in the following order: Ph3Si (19/1) < Me3Si (58/1) < Ph3Sn (90/1) < Me3Ge (100/1) < n-Bu3Sn (> 300/1). The allylation with allytributylstannane was significantly more selective than allytrimethylsilane for a number of chiral dioxane acetals examined.
• Studies on the mechanism and origin of stereoselective opening of chiral dioxane acetals
  作者：Scott E. Denmark、Neil G. Almstead

  DOI：10.1021/ja00021a040

  日期：1991.10

  A systematic examination of the mechanism and origin of stereoselection in the reaction of dioxane acetals with allyltrimethylsilane was undertaken. Experimental tests for two limiting mechanisms, synchronous (S(N)2-like) and dissociative (S(N)1-like) substitution processes, were investigated. The meso 2,4,6-trisubstituted 1,3-dioxane acetals cis- and trans-1 provided an interesting opportunity to test the timing of bond breaking and making in the substitution reaction. The modest and C(2)-substituent-dependent selectivity excluded the possibility of a direct S(N)2-type attack on a complexed acetal. Further, the enol ethers 3 and 5 and acyclic acetal 7 were studied as precursors of the putative oxocarbenium ion intermediate in the dissociative limit. The weak and inverted selectivity observed with these substrates ruled out the intermediacy of the extended, separated ion in reactions of the cyclic acetals under similar conditions. A unified mechanistic scheme involving three distinct ion pairs is proposed to explain the dependence of allylation selectivity on structural and experimental variables. The three species are analogous to those proposed in the classic Winstein scheme: (1) an intimate ion pair, (2) an external ion pair, and (3) a separated ion. Each of these proposed intermediates has a different stereochemical profile and the ultimate outcome is a composite of those factors that balance the contribution of the different intermediates. The influence of C(2) substituent, acetal configuration, Lewis acid type and stoichiometry, allylsilane stoichiometry, concentration, solvent, and temperature were investigated and integrated in the proposed mechanistic scheme.
• On the stereoselectivity opening of achiral dioxane acetals
  作者：Scott E. Denmark、Neil G. Almstead

  DOI：10.1021/jo00022a043

  日期：1991.10

  The stereoselectivity of allylation of achiral dioxane acetals cis- and trans-3 and cis- and trans-5 was found to be highly dependent on the nature of the allylmetal reagent, Lewis acid, and stoichiometry. Using TiCl2(O-i-Pr)2 as the Lewis acid in conjunction with allyltrimethylsilane and allyltri-n-butylstannane the selectivity of opening ranged from 1/1 to 18.6/1. In reactions with allyltrimethylsilane, the lack of selectivity for both the cis and trans series (1-2.4/1) was shown to arise from rapid equilibration of ion pairs. Control experiments revealed that the acetals underwent opening faster than isomerization. The reactions with allyltri-n-butylstannane were more selective and dependent on reagent stoichiometry. Moreover, the sense of asymmetric induction for the cis and trans series was opposite. Control experiments again established that isomerization of the acetals occurs slower than reaction with the stannane. These experiments unambiguously rule out the possibility that the opening proceeds via equilibrating ion pairs. The meso dioxane acetal cis-9 reacted with significantly reduced selectivity compared to the 2,4,6-trisubstituted analogue cis-7. On the other hand, the chiral acetal (+/-)-13 reacted much more selectively than the 2,4,6-trisubstituted analogue (+/-)-11. These reactions illustrate the sensitivity of stereochemical outcome to structural and experimental variables and demonstrate the ability to intercept reactive ion pairs under conditions of kinetic control.