SELECTIVE HYDROGENATION OF ALDEHYDE WITH RU/BIDENTATE LIGANDS COMPLEXES
申请人:FIRMENICH SA
公开号:US20140243526A1
公开(公告)日:2014-08-28
The present invention relates to processes for the reduction by hydrogenation, using molecular H
2
, of a C
5
-C
20
substrate containing one or two aldehydes functional groups into the corresponding alcohol or diol, characterized in that said process is carried out in the presence of —at least one catalyst or pre-catalyst in the form of a ruthenium complex having a coordination sphere of the N
2
P
2
O
2
, wherein the coordinating atoms N
2
are provided by a first bidentate ligand, the coordinating atoms P
2
are provided by a second bidentate ligand and the coordinating atoms O
2
are provided by two non-linear carboxylate ligands; and —optionally of an acidic additive.
Ruthenium-Catalyzed Highly Chemoselective Hydrogenation of Aldehydes
作者:Lucia Bonomo、Laurent Kermorvan、Philippe Dupau
DOI:10.1002/cctc.201500006
日期:2015.3
[dppe=1,2‐bis(diphenylphosphino)ethane] complex underbase‐free conditions allowed highly efficient and selective hydrogenation of aldehydes in the presence of ketones in addition to olefins. Even in the case of highly sensitive 1,6‐ketoaldehydes, the desired ketoalcohols were obtained in high yields with 94–99 % overall selectivity at complete aldehyde conversion with a TON up to 30 000. The lack of requirement
在无碱条件下使用[(乙二胺)(dppe)Ru(OCO t Bu)2 ] [dppe = 1,2-双(二苯基膦基)乙烷]配合物可以在存在下列条件的情况下对醛进行高效和选择性的加氢除烯烃外的酮。即使在高度敏感的1,6-酮醛的情况下,也可以在高醛的情况下以高达30000 TON的总醛转化率获得高产率,94-99%的总选择性的酮醇。对强碱性助催化剂的需求不足极性溶剂和质子传递溶剂还可以有效且高度化学选择性地还原带有其他官能团的醛,例如环氧化物,羧酸,酯,酰胺和腈,从而强调了催化剂的潜在合成用途。
Synthesis of a caryophyllene isoprenologue, a potential diterpene natural product
作者:Simon F.R. Hinkley、Nigel B. Perry、Rex T. Weavers
DOI:10.1016/j.tet.2005.02.018
日期:2005.4
(-)-beta-Caryophyllene has been converted into three stereoisomers of a new bicyclic compound that is structurally related to the known macrocyclic diterpene, flexibilene, in the same way beta-caryophyllene is related to humulene. Key steps are selective cleavage of caryophyllene, addition of a five carbon component by a Wittig reaction and McMurry cyclization. (c) 2005 Elsevier Ltd. All rights reserved.
Electron Transfer-Initiated Epoxidation and Isomerization Chain Reactions of β-Caryophyllene
作者:Bart Steenackers、Nicolò Campagnol、Jan Fransaer、Ive Hermans、Dirk De Vos
DOI:10.1002/chem.201404711
日期:2015.1.26
polar aprotic solvents, the reaction proceeds smoothly with epoxide selectivities exceeding 70 %. A mechanistic study has been performed and the possible involvement of free radical, spin inversion, and electron transfer mechanisms is evaluated using experimental and computational methods. The experimental data—including a detailed reaction product analysis, studies on reaction parameters, solvent effects
在没有任何催化剂的情况下,大量的倍半萜烯β-叶绿素烯可以被分子氧环氧化。在极性非质子溶剂中,反应平稳进行,环氧化物选择性超过70%。已经进行了机理研究,并使用实验和计算方法评估了自由基,自旋反转和电子转移机制的可能参与。实验数据(包括详细的反应产物分析,反应参数研究,溶剂作用,添加剂和电化学研究)均支持β-叶绿素的自发环氧化反应是在以下条件下罕见的从烯烃到三重态氧的不敏感电子转移的案例温和条件(80°C,1 bar O 2)。作为引发氧化反应的一种方法,有人提出了通过电子转移形成石竹烯衍生的自由基阳离子的方法。该自由基阳离子在优化的条件下通过链长超过100的链机理与三线态氧反应生成二氧杂环丁烷。然后,二氧杂环丁烷充当原位形成的环氧化剂。在氮气氛下,单电子受体的存在会导致β-石竹烯选择性异构化为异烟酰胺。观察表明,这种异构化反应是异烟肼的新颖而优雅的合成途径。
A Concise Bioinspired Semisynthesis of Rumphellaones A–C and Their C-8 Epimers from β-Caryophyllene
their C-8 epimers as well as the shortest synthesis of rumphellaone A (1) and its C-8 epimer from the most accessible sesquiterpene, β-caryophyllene (4), is presented. Synthetic routes involved caryophyllonic acid as a key intermediate, which was converted to rumphellaone A (and epimer) via acid-catalyzed lactonization and rumphellaone C (and epimer) using one-pot epoxidation–lactonization. Rumphellaone
朝向rumphellaones B(第一半合成路线2)和C(3)和它们的C-8差向异构体以及rumphellaone A(最短合成1),并从最容易获得的倍半萜,β石竹其C-8差向异构体(4), 被表达。合成路线涉及石竹酸作为关键中间体,通过酸催化内酯化将其转化为鹿鞭草酮 A(和差向异构体),并使用一锅环氧化 - 内酯化将鹿鞭草酮 C(和差向异构体)。Rumphellaone B ( 2 ) 及其差向异构体是从rumphellaone A ( 1) 及其差向异构体,分别使用 Saegusa-Ito 氧化。C-8 处的绝对构型通过对rumphellaone B ( 2 ) 和rumphellaone C 的酰化衍生物进行单晶X 射线分析证实。