(RS)-5-ethyl-5,6-dihydropyran-2-one | 88981-50-4

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃
• 英文名称: (RS)-5-ethyl-5,6-dihydropyran-2-one
• 英文别名: (+/-)-5-Ethyl-5,6-dihydro-2-pyrone；2H-Pyran-2-one, 5-ethyl-5,6-dihydro-；3-ethyl-2,3-dihydropyran-6-one
• CAS: 88981-50-4
• 化学式: C₇H₁₀O₂
• 分子量: 126.155
• InChiKey: IARPNQQEBPSAAE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.4
• 重原子数：
  9
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.57
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (RS)-5-ethyl-5,6-dihydropyran-2-one 以71%的产率得到
  参考文献：
  名称：

  FLEMING, IAN;REDDY, N. LAXMA;TAKAKI, KEN;WARE, ANNE C., J. CHEM. SOC. CHEM. COMMUN.,(1987) N 19, 1472-1474

  摘要：

  DOI：
• 作为产物：
  描述：

  2-(tert-butyldimethylsilanyloxymethyl)-1-butanol 在 草酰氯 、 四丁基氟化铵 、 potassium hydride 、 二甲基亚砜 作用下， 以 四氢呋喃 、 二氯甲烷 为溶剂， 反应 16.75h， 生成 (RS)-5-ethyl-5,6-dihydropyran-2-one
  参考文献：
  名称：

  Ihara, Masataka; Yasui, Ken; Taniguchi, Nobuaki, Journal of the Chemical Society. Perkin transactions I, 1990, # 5, p. 1469 - 1476

  摘要：

  DOI：

文献信息

• Stereocontrol in organic synthesis using silicon-containing compounds. Studies directed towards the synthesis of ebelactone AElectronic supplementary information (ESI) available: Experimental section. See http://www.rsc.org/suppdata/ob/b3/b316899a/
  作者：Sarah C. Archibald、David J. Barden、J�r�me F. Y. Bazin、Ian Fleming、Colin F. Foster、Ajay K. Mandal、Amit K. Mandal、David Parker、Ken Takaki、Anne C. Ware、Anne R. B. Williams、Anna B. Zwicky

  DOI：10.1039/b316899a

  日期：——

  Several approaches to the synthesis of ebelactone A 2 are described, culminating in the synthesis of the benzenesulfonate of 2-epi-ebelactone A 161. All the approaches were based on three fragments A, B and C, originally defined in general terms in, but eventually used as the aldehyde 72, the allenylsilane 3 and the aldehyde 139, respectively. They were joined, first B with C, and then B+C with A.

  描述了几种合成依贝内酯A 2的方法，最终合成了2-表皮-依贝内酯A 161的苯磺酸盐。所有方法均基于三个片段A，B和C，它们最初是在通用术语中定义的，但最终用作醛72，烯丙基硅烷3和醛139。他们先加入B，再加入C，然后再加入B + C，再加入A。在通往片段A和C的主要途径中，相对立体化学是由高度立体选择性烯醇酸甲基化67-> 67、68-> 69和135-> 136，在每种情况下均抗相邻的甲硅烷基，并且通过烯丙基硅烷137-> 138的高度立体选择性氢硼化，也抗甲硅烷基。原定位于C-3和C-11上的羟基未被甲硅烷基向羟基的转化作用69-> 70和138->掩盖 139，保留配置。片段B与C偶联过程中产生的立体化学是通过对映体富集的烯丙基硅烷3和醛139之间的立体特异性抗S（E）2'反应控制的。 ，并通过乙烯基硅烷的碘去甲硅烷基化151-> 152保留构型，并通过Nozaki-Hiyama
• Stereochemistry of conjugate addition to 4- and 5-substituted α,β-unsaturated δ-lactones
  作者：Ian Fleming、N. Laxma Reddy、Ken Takaki、Anne C. Ware

  DOI：10.1039/c39870001472

  日期：——

  Conjugate addition, especially of the phenyldimethylsilylcuprate reagent, to 4- and 5-substituted α,β-unsaturated δ-lactones [(5) and (18)] is highly selective for the formation of the trans-products [(6), (7), (9), (10), and (19)], the silicon-containing products having 1H n.m.r. coupling constants indicative of distortions from the chair conformation; the silyl group can be converted into a hydroxy

  共轭加成，特别是苯基二甲基甲硅烷基铜酸酯试剂向4和5取代的α，β-不饱和δ-内酯[（5）和（18）]的加成对形成反式产物[（6），（图7），（9），（10）和（19）]，具有1 H nmr耦合常数的含硅产物表示椅子构象的变形；甲硅烷基可以转化为羟基以得到内酯（8）和（20）。
• Kinetic Resolution of Racemic Lactones by Conjugate Additions of Allylic Organolithium Species:  Direct Formation of Three Contiguous Centers with High Diastereo- and Enantioselectivities
  作者：Sung H. Lim、Peter Beak

  DOI：10.1021/ol0263898

  日期：2002.8.1

  [reaction: see text] Kinetic resolution of racemic alpha,beta-unsaturated lactones by the organolithium species produced from asymmetric lithiation of N-Boc-N-(p-methoxyphenyl)cinnamylamine provides conjugate addition products with three contiguous stereogenic centers in yields of 62-77% with diastereomeric ratios from 75:25 to >99:1 and enantiomeric ratios for the major diastereomers from 94:6 to 98:2

  [反应：请参阅文本] N-Boc-N-（对甲氧基苯基）肉桂胺的不对称锂化所产生的有机锂物种可动态消解外消旋的α，β-不饱和内酯，可提供具有三个连续立体中心的共轭加成产物，产率为62 -77％的非对映体比例为75:25至> 99：1，主要非对映体的对映体比例为94：6至98：2。
• Use of pyridinium chlorochromate as methylene oxidant in 5,6-dihydropyrans: a practical one-step preparation of the anhydromevalonolactone
  作者：Francesco Bonadies、Romano Di Fabio、Carlo Bonini

  DOI：10.1021/jo00183a030

  日期：1984.5
• A Chiral Pentenolide-Based Unified Strategy toward Dihydrocorynantheal, Dihydrocorynantheol, Protoemetine, Protoemetinol, and Yohimbane
  作者：Changmin Xie、Jisheng Luo、Yan Zhang、Lili Zhu、Ran Hong

  DOI：10.1021/acs.orglett.7b01573

  日期：2017.7.7

  An organocatalytic cross-aldol reaction of formaldehyde (formalin) with alkyl aldehydes, followed by the Z-selective Horner-Wadsworth-Emmons (HWE) reaction and immediate lactonization, afforded gamma-alkylated pentenolides in good overall yields and excellent enantioselectivities. Based on this scalable sequence, five quinolizidine alkaloids were synthesized in a unified and concise manner. The development of an in situ activation of a tertiary amide to improve the efficiency of the Bischler-Napieraiski (B-N) reaction was also noteworthy due to the generality to sensitive substrates for a variety of target molecules.