| 134236-71-8

• 分子结构分类: 有机化合物 - 有机杂环化合物
• CAS: 134236-71-8
• 化学式: C₁₅H₂₄O₃
• 分子量: 252.354
• InChiKey: UCEUCSZRNQHMDC-KBPBESRZSA-N

反应信息

• 作为产物：
  描述：

  (5R*,6R*)-1,7-dioxaspiro<4.0.4.4>tetradec-12-en-11-one 在 palladium on activated charcoal 4-二甲氨基吡啶 、 indium 、 sodium hydroxide 、 9-borabicyclo[3.3.1]nonane dimer 、 正丁基锂 、 氢气 、 双氧水 、 三乙胺 、 对甲苯磺酰氯 作用下， 以 四氢呋喃 、 二氯甲烷 、 乙酸乙酯 为溶剂， 反应 18.75h， 生成
  参考文献：
  名称：

  Definition of Several Control Elements Relevant to the Stereodefined Serial Elaboration of Belted Poly(spirotetrahydrofurans) Fitted with a Cyclohexane Core

  摘要：

  The stereochemistry of the condensations of 2-cyclohexenones, alpha-arylidenecyclohexanones, and alpha-(tert-butyldimethylsiloxy)cyclohexanones carrying one or two (both syn and anti) spirotetra-hydrofuran units adjacent to the carbonyl with allyl organometallics (especially indium) and with the Normant reagent (ClMgO(CH2)(3)MgCl) is described. Good levels of anti stereoselection are observed in the alpha-arylidene series. Subsequent cyclization generates a second (or third) tetrahydrofuran ring possessing trans vicinal oxygens. Useful levels of matched and mismatched diastereoselection are also attainable by prior alpha-oxygenation, The intrinsic differences in diastereomer production between indium and magnesium organometallics are highlighted. A clear distinction regarding the anticipated direction of stereoselectivity is made on the grounds of chelation capabilities and the intra- or intermolecularity of carbon-carbon bond formation. Finally, the two protocols that are described in detail are shown to be iterative, a feature that augurs well for ultimately accessing the eight possible hexaspirocyclohexanes in an efficient and stereocontrolled manner.

  DOI：

  10.1021/jo960962h

文献信息

• Synthesis and molecular structure of belted spirocyclic tetrahydrofurans, a new class of preorganized hosts for cations
  作者：Leo A. Paquette、Joanna T. Negri、Robin D. Rogers

  DOI：10.1021/jo00040a041

  日期：1992.7

  The preparation and binding properties of spirocyclic tetrahydrofurans 7-11 are described. The condensation of cyclopentanone with 5-lithio-2,3-dihydrofuran (12) provided an alcohol which readily rearranged to ketone 14 under acidic conditions. ''Capping'' of the carbonyl group in 14 so as to generate a second spiro tetrahydrofuran subunit gave rise to 7 and 8. Starting with cyclobutanone, 2-fold ring expansion involving 12 provided the key reactions leading to 22 and 23, which were 'capped' as before. Crystal structure data are available for 9, 11, and 22. In addition, the variable-temperature NMR behavior of 7 and 10 was quantified by means of 2-D measurements. A detailed analysis is presented that shows the gauche effect to be of major importance in dictating the major conformation adopted by these ionophores. The binding properties of 7-11 have been assayed. Considerable variation was found, the efficiency being critically dependent upon the number of oxygen atoms, the relative stereochemistry of the C-O bonds, and the relative ease of conformational readjustment necessary to achieve proper organization around the oxophilic metal ion.