N'-dioxide-Sc(III) complex catalysts. The BV oxidations of prochiral cyclohexanones and cyclobutanones afforded series of optically active ε- and γ-lactones, respectively, in up to 99% yield and 95% ee. Meanwhile, the kinetic resolution of racemic 2-arylcyclohexanones was also realized via an abnormal BV oxidation. Enantioenriched 3-aryloxepan-2-ones, whose formation is counter to the migratoryaptitude, were
Functional divergence between closely related Baeyer-Villiger monooxygenases from Aspergillus flavus
作者:F.M. Ferroni、M.S. Smit、D.J. Opperman
DOI:10.1016/j.molcatb.2014.05.015
日期:2014.9
well-characterized BVMOs including cyclohexanone, phenylacetone and 4-hydroxyacetophenone monooxygenase. Building on the Grogan classification/clustering of BVMOs, we have designated this new group of BVMOs, Group VI. Group VI BVMOs show an early divergence from the cyclopentanone monooxygenase (CPMO) type BVMOs (Group I). Substrate profiling using cyclic, bicyclic, aliphatic and aryl ketones show a clear divergence
Assessing the Substrate Selectivities and Enantioselectivities of Eight Novel Baeyer−Villiger Monooxygenases toward Alkyl-Substituted Cyclohexanones
作者:Brian G. Kyte、Pierre Rouvière、Qiong Cheng、Jon D. Stewart
DOI:10.1021/jo030253l
日期:2004.1.1
4-alkyl-substituted cyclohexanones tested, enzymes were discovered that afforded each of the corresponding (S)-lactones in ≥98% ee. This was also true for the 2-alkyl-substituted cyclohexanones examined. The situation was more complex for 3-akyl-substituted cyclohexanones. In a few cases, single Baeyer−Villiger monooxygenases possessed both high regio- and enantioselectivities toward these compounds
Total synthesis of coronafacic acid through 6-endo-trig mode intramolecular cyclization of an enone-aldehyde to a hydrindanone using samarium(II) iodide
作者:Masakazu Sono、Atsuko Hashimoto、Katsuyuki Nakashima、Motoo Tori
DOI:10.1016/s0040-4039(00)00786-3
日期:2000.6
Coronafacic acid has been synthesized from a hydrindanone prepared by a 6-endo-trig mode cyclization reaction of the enone-aldehyde with samarium(II) iodide. The stereochemistry of the hydrindanone was controlled by the coordinated samarium species resulting in cis in respect of the hydroxyl group at C-4 and the juncture proton at C-3a.
Selective Nickel-Catalyzed Conversion of Model and Lignin-Derived Phenolic Compounds to Cyclohexanone-Based Polymer Building Blocks
作者:Wouter Schutyser、Sander Van den Bosch、Jan Dijkmans、Stuart Turner、Maria Meledina、Gustaaf Van Tendeloo、Damien P. Debecker、Bert F. Sels
DOI:10.1002/cssc.201403375
日期:2015.5.22
Valorization of lignin is essential for the economics of future lignocellulosic biorefineries. Lignin is converted into novel polymerbuildingblocks through four steps: catalytic hydroprocessing of softwood to form 4‐alkylguaiacols, their conversion into 4‐alkylcyclohexanols, followed by dehydrogenation to form cyclohexanones, and Baeyer–Villiger oxidation to give caprolactones. The formation of alkylated
木质素的增价对于未来木质纤维素生物精炼厂的经济性至关重要。木质素通过以下四个步骤转化为新型的聚合物结构单元:针叶木的催化加氢处理形成4-烷基愈创木酚,将其转化为4-烷基环己醇,然后脱氢形成环己酮,以及Baeyer-Villiger氧化生成己内酯。烷基化环己醇的形成是该系列中最困难的步骤之一。在CeO 2或ZrO 2上存在镍的液相过程本文证明了催化剂可产生最高的环己醇收率。与4-烷基愈创木酚的催化反应遵循两条平行的途径,且速率相近:1)环加氢形成相应的烷基化2-甲氧基环己醇,以及2)脱甲氧基化形成4-烷基苯酚。尽管随后的苯酚向环己醇的转化速度很快,但从2-甲氧基环己醇中除去甲氧基的速率受到限制。总的来说,这最后一个反应是限速步骤,需要足够的温度(> 250°C)才能克服能垒。Ni / CeO 2的底物反应性(相对于烷基链的类型)和反应速率的催化剂特性(镍负载量和镍粒度)的细节已详细报道。催化剂。最好的Ni