25766-18-1Relevant articles and documents
Synthesis of nopol via Prins condensation of β-pinene and paraformaldehyde catalyzed by sulfated zirconia
Jadhav, Sumit V.,Jinka, Krishna Mohan,Bajaj, Hari C.
, p. 158 - 165 (2010)
The present work describes the novel application of sulfated zirconia (SZ) solid acid catalysts for the synthesis of nopol via Prins condensation of β-pinene and paraformaldehyde. SZ catalysts with different percentages of sulfur loadings have been synthesized and characterized using various physico-chemical techniques like PXRD, FT-IR, surface area analysis and NH 3-TPD studies. The influences of various reaction parameters such as sulfur loading, reaction temperature, molar ratio of reactants, reaction time, solvent effect and reusability of the catalyst have been investigated. SZ catalyst synthesized by impregnation of 2N sulfuric acid solution over Zr(OH)4 was found to be a highly selective catalyst for β-pinene conversion (>99%) with ～99% selectivity to nopol. The catalyst could be reused up to five cycles with minor loss in catalytic activity for β-pinene conversion, while the nopol selectivity remains unaffected.
A comparative study of solvent-free and highly efficient pinene hydrogenation over pd on carbon, alumina, and silica supports
Selka, Ayyoub,Levesque, Natalie A.,Foucher, Delphine,Clarisse, Olivier,Chemat, Farid,Touaibia, Mohamed
, p. 60 - 64 (2017)
Solvent-free catalytic hydrogenation of pinene over Pd on carbon, alumina, and silica supports were compared. Despite the absence of solvent, Pd catalyst on all three supports yields to a quantitative conversion of pinene to pinanes and a higher selectivity for the cis isomer (72-89%). The temperature affected similarly the selectivity of the reaction for all three catalysts in favor of the cis-pinane isomer. However, recycling of the Pd on the three tested supports varied greatly. If Pd/C and Pd/alumina were successfully recycled 13 and 14 times, respectively, Pd/silica could be used only once to convert pinenes into pinanes. Remaining very effective during all 13 cycles, Pd/C was the best catalyst/support of the three tested ones for the solvent-free hydrogenation of pinene. The influence of H2 pressure on pinene conversion rates were investigated for Pd/C catalyst. An extremely low leaching rate of palladium in pinenes and pinanes determined by ICP/MS confirmed the heterogeneous nature of this catalytic solvent-free reaction. The hydrogenation reaction presented in this paper is an alternate environmentally friendly pathway for pinane synthesis.
SYNTHESE VON ISOPINOCAMPHEYLHALOGENBORANEN UND IHRE VERWENDUNG ALS CHIRALE KATALYSATOREN FUER ASYMMETRISCHE DIELS-ALDER-REAKTIONEN
Bir, Gerhard,Kaufmann, Dieter
, p. 777 - 780 (1987)
The synthesis of a number of mono- and diisopinocampheylhalogenboranes is described.Their ability to act as chiral catalysts in asymmetric Diels-Alder reactions has been investigated in case of the reaction of cyclopentadiene with methacroleine.
Method and Means for Releasing a Terpene Mixture to a Cannabis Flower During Storage
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, (2021/09/17)
A method and means for releasing a terpene mixture to a Cannabis flower during storage with may be from a cotton pulp card or a two-way humidity pack with an additional terpene blend for keeping a Cannabis flower fresh while naturally increasing the desired terpene levels. The product is a blend of humidity regulating agents infused with terpenes (plant derived) which allows for the product to be paired with herbal material to increase and maintain the relative humidity, while transferring the flavor/aroma/taste terpenes from the package into the herbal material. There are two embodiments, the first is a Terp Pack+Humidity (“Terp Pack+RH”) which contains a herban material to increase and maintain relative humidity, while releasing the infused terenes, and the second is more simply a Terp Pack (“Terp Pack”) which contains no humidity enhancing material and is only a carrier for releasing the terpene mixture.
Iron Catalyzed Double Bond Isomerization: Evidence for an FeI/FeIII Catalytic Cycle
Woof, Callum R.,Durand, Derek J.,Fey, Natalie,Richards, Emma,Webster, Ruth L.
supporting information, p. 5972 - 5977 (2021/03/17)
Iron-catalyzed isomerization of alkenes is reported using an iron(II) β-diketiminate pre-catalyst. The reaction proceeds with a catalytic amount of a hydride source, such as pinacol borane (HBpin) or ammonia borane (H3N?BH3). Reactivity with both allyl arenes and aliphatic alkenes has been studied. The catalytic mechanism was investigated by a variety of means, including deuteration studies, Density Functional Theory (DFT) and Electron Paramagnetic Resonance (EPR) spectroscopy. The data obtained support a pre-catalyst activation step that gives access to an η2-coordinated alkene FeI complex, followed by oxidative addition of the alkene to give an FeIII intermediate, which then undergoes reductive elimination to allow release of the isomerization product.
Amphiphilic polymeric nanoreactors containing Rh(i)-NHC complexes for the aqueous biphasic hydrogenation of alkenes
Allandrieu, Audrey,Coppel, Yannick,Daran, Jean-Claude,Gayet, Florence,Hromov, Roman,Labande, Agnès,Manoury, Eric,Poli, Rinaldo,Ruzhylo, Illia,Sabatier, Cassandra,Sambou, Sasaline Salomon,Wang, Hui
, p. 6811 - 6824 (2021/10/25)
A rhodium(i) complex bearing a monodentate N-heterocyclic carbene ligand has been confined into the core of amphiphilic polymeric core-crosslinked micelles (CCMs). The Rh complex was covalently bound to the polymeric chains by incorporation of a polymerizable unit on the NHC ligand. Nanoreactor Rh-NHCmes@CCM5bhas been evaluated as a catalyst for the aqueous biphasic hydrogenation of styrene and other alkenes. It has shown a high activity with styrene at a low catalytic loading (10?000/1 substrate/Rh ratio), greater than that of an analogous molecular Rh(i) complex, and its evolution to Rh0is slower. This is attributed to several factors, among which the confinement effect and the favourable polyoxygenated environment of the nanoreactor core. Finally, the CCMs could be recycled up to four times with almost no loss of activity over 3 h cycles and the loss of rhodium per cycle was on average lower than 0.6 ppm.
Iron-Catalyzed C-C Single-Bond Cleavage of Alcohols
Liu, Wei,Wu, Qiang,Wang, Miao,Huang, Yahao,Hu, Peng
supporting information, p. 8413 - 8418 (2021/11/01)
An iron-catalyzed deconstruction/hydrogenation reaction of alcohols through C-C bond cleavage is developed through photocatalysis, to produce ketones or aldehydes as the products. Tertiary, secondary, and primary alcohols bearing a wide range of substituents are suitable substrates. Complex natural alcohols can also perform the transformation selectively. A investigation of the mechanism reveals a procedure that involves chlorine radical improved O-H homolysis, with the assistance of 2,4,6-collidine.
Highly Selective Hydrogenation of C═C Bonds Catalyzed by a Rhodium Hydride
Gu, Yiting,Lisnyak, Vladislav G.,Norton, Jack R.,Salahi, Farbod,Snyder, Scott A.,Zhou, Zhiyao
supporting information, p. 9657 - 9663 (2021/07/19)
Under mild conditions (room temperature, 80 psi of H2) Cp*Rh(2-(2-pyridyl)phenyl)H catalyzes the selective hydrogenation of the C═C bond in α,β-unsaturated carbonyl compounds, including natural product precursors with bulky substituents in the β position and substrates possessing an array of additional functional groups. It also catalyzes the hydrogenation of many isolated double bonds. Mechanistic studies reveal that no radical intermediates are involved, and the catalyst appears to be homogeneous, thereby affording important complementarity to existing protocols for similar hydrogenation processes.
Synthetic method of chiral alcohol compound with 6 carbon skeleton structure
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Paragraph 0025-0027, (2020/03/16)
To the invention, 6 pinene is used as the chiral auxiliary, and the chiral auxiliary compound (-) - a - is finally quenched and hydrolyzed to form the chiral alcohol pure, final product, with the purity 3, value, not only can obtain the target product, with high chiral purity and content, but also can carry out commercialized production, HPLC. 98.1%; The chiral alcohol compound has an. ideal yield 97.4%,e.e.
Palladium nanoparticles stabilized by novel choline-based ionic liquids in glycerol applied in hydrogenation reactions
Garg, Garima,Foltran, Stéphanie,Favier, Isabelle,Pla, Daniel,Medina-González, Yaocihuatl,Gómez, Montserrat
, p. 69 - 75 (2019/02/16)
Palladium nanoparticles stabilized by choline-based ionic liquids in glycerol were prepared from Pd(II) precursors by simply heating at 80 °C under argon; in this process, the water present in the ionic liquid was found to be responsible for the reduction of Pd(II) into zero-valent palladium species. Palladium nanoparticles were fully characterized in both liquid phase and solid state. The as-prepared metal nanoparticles exhibited remarkable catalytic activity in hydrogenation processes for a significant variety of functional groups (alkenes, alkynes, nitro derivatives, benzaldehydes, aromatic ketones).
