90820-79-4Relevant academic research and scientific papers
An ultrathin amino-acid based copper(II) coordination polymer nanosheet for efficient epoxidation of β-caryophyllene
Fu, Zaihui,Huang, Hongmei,Mao, Liqiu,Mao, Wensheng,Shi, Lihan,Xiao, Yi,Yin, Dulin,Yu, Ningya,Zhang, Li,Zhao, Yaqian
, (2021/07/26)
Natural amino acids are important building blocks for the construction of intriguing coordination polymers (CPs) because of their abundance, inexpensiveness and environmental benignness. Herein, two copper(II) CPs, namely, 2D CuIle-e nanosheet (e: ethanol) and 1D CuIle-m nanoshuttle (m: methanol), were fabricated from L-isoleucine (Ile) and well characterized with single-crystal x-ray diffraction, XPS spectra, TEM and AFM, etc. More importantly, two novel and stable catalytic nanosystems, i.e. CuIle-e/acetone/TBHP (tert-butyl hydroperoxide) and CuIle-e/THF/O2/TBHP, were thus conveniently built by using ultrathin 2D CuIle-e nanosheet (~ 2.3 nm) in suitable aprotic solvents. Under mild conditions, complete conversion of β-caryophyllene and good yields (86.1% or 87.2%) for β-caryophyllene epoxide were gained via CuIle-e/acetone/TBHP or CuIle-e/THF/O2 (1 atm)/TBHP (10.0 mol%), respectively. Notably, ultrathin CuIle-e nanosheet showed fairly satisfactory stability, which may open a unique window for the facile fabrication of new amino-acid based CP nanosystems with outstanding catalytic performances in actual applications.
Ionic liquid-mediated catalytic oxidation of β-caryophyllene by ultrathin 2D metal-organic framework nanosheets under 1 atm O2
Li, Shiye,Shi, Lihan,Zhang, Li,Huang, Hongmei,Xiao, Yi,Mao, Liqiu,Tan, Rong,Fu, Zaihui,Yu, Ningya,Yin, Dulin
, (2020/09/16)
An ionic liquid (IL)-mediated facile method was established for the epoxidation of β-caryophyllene with molecular oxygen using ultrathin (～3?6 nm) 2D Cu-, Co- or Ce-based MOF nanosheets. Under the optimum conditions, high selectivity (92.4percent) and excellent yield (86.7percent) for β-caryophyllene epoxide were obtained over ultrathin (～5.5 nm) Cu-TCPP nanosheets (TCPP = tetrakis(4-carboxyphenyl)porphyrin) with the aid of [C12mim]Cl at 313 K and 1 atm O2. Notably, a small amount of [C12mim]Cl (1-dodecyl-3-methylimidazolium chloride, 5.0 mol percent) played pivotal roles in forming a favorable microenvironment in-situ, thus significantly improving the catalytic performances of above-mentioned Cu-TCPP nanosheets containing PVP stabilizer. Moreover, ultrathin Cu-TCPP nanosheets showed better stability during β-caryophyllene transformation in the presence of amphiphilic [C12mim]Cl, as supported by TEM and XRD analyses. Importantly, the addition of TBHP (tert-butyl hydroperoxide, 13.0 mol percent) initiator is also crucial for the aerobic oxidation of β-caryophyllene via Cu-TCPP nanosheets/[C12mim]Cl/TBHP/O2 nanosystem. Further insights into the synergistic effects and free radical mechanism were achieved by fluorescence, DRUV-Vis, UV-vis and XPS measurements.
Erratum: Removal of the E-Olefin Barrier of Humulene Leading to Unnatural Terpenoid-like Skeletons (Organic Letters (2018) 20, 22, (7313-7320) DOI: 10.1021/acs.orglett.8b03259)
Nishimura, Takehiro,Kawai, Junya,Oshima, Yoshiteru,Kikuchi, Haruhisa
supporting information, p. 1241 - 1241 (2019/05/16)
The structures of compounds 11 and 12 shown in Figure 2A were corrected by changing the relative configurations, although the structures in the Supporting Information were correct. Figure 2A is corrected as follows: The absolute configurations of compounds 15-19 drawn in Figure 3A and in the Supporting Information were corrected. Although the relative configurations shown in the Supporting Information were correct, the wrong assignment is because of drawing the absolute configuration at the C-6 position of 15- 17 in reverse. The corrected Figure 3A is as follows and and the revised Supporting Information with the corrected structures for compounds 15-17 is included with this Correction.
Cobalt-Catalyzed Regioselective Olefin Isomerization under Kinetic Control
Liu, Xufang,Zhang, Wei,Wang, Yujie,Zhang, Ze-Xin,Jiao, Lei,Liu, Qiang
supporting information, p. 6873 - 6882 (2018/05/30)
Olefin isomerization is a significant transformation in organic synthesis, which provides a convenient synthetic route for internal olefins and remote functionalization processes. The selectivity of an olefin isomerization process is often thermodynamically controlled. Thus, to achieve selectivity under kinetic control is very challenging. Herein, we report a novel cobalt-catalyzed regioselective olefin isomerization reaction. By taking the advantage of fine-tunable NNP-pincer ligand structures, this catalytic system features high kinetic control of regioselectivity. This mild catalytic system enables the isomerization of 1,1-disubstituted olefins bearing a wide range of functional groups in excellent yields and regioselectivity. The synthetic utility of this transformation was highlighted by the highly selective preparation of a key intermediate for the total synthesis of minfiensine. Moreover, a new strategy was developed to realize the selective monoisomerization of 1-alkenes to 2-alkenes dictated by installing substituents on the γ-position of the double bonds. Mechanistic studies supported that the in situ generated Co-H species underwent migratory insertion of double bond/β-H elimination sequence to afford the isomerization product. The less hindered olefin products were always preferred in this cobalt-catalyzed olefin isomerization due to an effective ligand control of the regioselectivity for the β-H elimination step.
Removal of the E-Olefin Barrier of Humulene Leading to Unnatural Terpenoid-like Skeletons
Nishimura, Takehiro,Kawai, Junya,Oshima, Yoshiteru,Kikuchi, Haruhisa
supporting information, p. 7317 - 7320 (2018/11/25)
An unnatural terpenoid scaffold containing a bicyclo[5.4.0]undecane moiety, as well as a salvialane skeleton based on an intramolecular C-C bond formation strategy were synthesized. Such a strategy was made possible by the removal of strained E-olefin conformations of the humulene skeleton. Some compounds were identified to show PPARα antagonist activity.
Where is the Oxygen? Structural Analysis of α-Humulene Oxidation Products by the Crystalline Sponge Method
Zigon, Nicolas,Hoshino, Manabu,Yoshioka, Shota,Inokuma, Yasuhide,Fujita, Makoto
supporting information, p. 9033 - 9037 (2015/08/03)
Crystal structures of α-humulene, a cyclic sesquiterpene, and its oxidized subproducts, were analyzed by the crystalline sponge method. Regio- and stereochemistry, including absolute configuration when a chiral oxidant was applied, and the stable conformations of all the scaffold-related compounds were successfully determined for samples on a 5-50 μg scale.
Simple, chemoselective, catalytic olefin isomerization
Crossley, Steven W. M.,Barabé, Francis,Shenvi, Ryan A.
supporting information, p. 16788 - 16791 (2015/01/09)
Catalytic amounts of Co(SaltBu,tBu)Cl and organosilane irreversibly isomerize terminal alkenes by one position. The same catalysts effect cycloisomerization of dienes and retrocycloisomerization of strained rings. Strong Lewis bases like amines and imidazoles, and labile functionalities like epoxides, are tolerated.
A stable rearrangement product of humulene-4,5-epoxide
Carman, Raymond M.
, p. 1441 - 1442 (2008/09/20)
Humulene-4,5-monoepoxide, 1, may rearrange to the cyclopropyl diol 2 during chromatography over silica. The rearrangement can be reversed with acid.
Transformations of α-Humulene and Some Its Monoepoxy Derivatives over Solid Acid Catalysts. Epoxidation of α-Humulene
Khomenko,Zenkovets,Barkhash
, p. 595 - 600 (2007/10/03)
2,3- and 6,7-Epoxy derivatives of α-humulene in liquid superacids at low temperatures and over solid catalysts at room temperature undergo isomerizations whose direction is determined by conformational factors.
Hydrolysis and Reversible Isomerization of Humulene Epoxides II and III
Yang, Xiaogen,Deinzer, Max L.
, p. 4717 - 4722 (2007/10/02)
The hydrolysis reactions of humulene epoxide II (3) and humulene epoxide III (4) were studied on aqueous solution at pH 4.0.Twelve compounds from the hydrolysis of humulene epoxide II and 16 from humulene epoxide III were separated and identified.All of the compounds identified from hydrolyis of 3 also were found among the hydrolysis products of 4.A reversible transformation between these two epoxides proceeding through a bicyclic diol (15) as intermediate is responsible for producing the same products.Hydrolysis reactions further yielded diols and a number of different ring systems.The apparent intermediacy of carbocations also led to several elimination reaction products.Among the products identified from these epoxides, six have not been reported before.These are 1,5,8,8-tetramethyl-12-oxa-5-tricyclo6,9>dodecene (1), 4,8,11,11-tetramethyl-8-tricyclo2,5>undecen-5-ol (5), stereoisomers of 2,6,6,9-tetramethyltricyclo2,4>undecane-5,9-diol (10, 14), 1,5,8,8-tetramethyl-8-bicycloundecene-2,9-diol (15), and the stereoisomeric pair 4,8,11,11-tetramethyltricyclo2,4>undecane-5,9-diol (16).
