7785-26-4Relevant articles and documents
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).
Controllable Isomerization of Alkenes by Dual Visible-Light-Cobalt Catalysis
Meng, Qing-Yuan,Schirmer, Tobias E.,Katou, Kousuke,K?nig, Burkhard
supporting information, p. 5723 - 5728 (2019/04/03)
We report herein that thermodynamic and kinetic isomerization of alkenes can be accomplished by the combination of visible light with Co catalysis. Utilizing Xantphos as the ligand, the most stable isomers are obtained, while isomerizing terminal alkenes over one position can be selectively controlled by using DPEphos as the ligand. The presence of the donor–acceptor dye 4CzIPN accelerates the reaction further. Transformation of exocyclic alkenes into the corresponding endocyclic products could be efficiently realized by using 4CzIPN and Co(acac)2 in the absence of any additional ligands. Spectroscopic and spectroelectrochemical investigations indicate CoI being involved in the generation of a Co hydride, which subsequently adds to alkenes initiating the isomerization.
High-activity cobalt catalysts for alkene hydroboration with electronically responsive terpyridine and α-diimine ligands
Palmer, W. Neil,Diao, Tianning,Pappas, Iraklis,Chirik, Paul J.
, p. 622 - 626 (2015/03/04)
Cobalt alkyl complexes bearing readily available and redox-active 2,2′:6′,2″-terpyridine and α-diimine ligands have been synthesized, and their electronic structures have been elucidated. In each case, the supporting chelate is reduced to the monoanionic, radical form that is engaged in antiferromagnetic coupling with the cobalt(II) center. Both classes of cobalt alkyls proved to be effective for the isomerization-hydroboration of sterically hindered alkenes. An α-diimine-substituted cobalt allyl complex proved exceptionally active for the reduction of hindered tri-, tetra-, and geminally substituted alkenes, representing one of the most active homogeneous catalysts known for hydroboration. With limonene, formation of an η3-allyl complex with a C-H agostic interaction was identified and accounts for the sluggish reactivity observed with diene substrates. For the terpyridine derivative, unique Markovnikov selectivity with styrene was also observed with HBPin. (Figure Presented).
PHOTOLABILE PRO-FRAGRANCES
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Page/Page column 8-9, (2012/12/14)
Photolabile scent storage substance that are capable of photoinduced release of cyclic compounds have at least one cyclic double bond. These scent storage substances are special ketones, and enable greatly improved stability of the scent impression, in particular with a fresh character, in typical applications, for example in textile laundering, room scenting, and in the cosmetic sector. More economical utilization of the stored scents can thereby be ensured. Also described are corresponding washing or cleaning agents, scenting methods, and methods for manufacturing the special ketones.
An efficient method for the transformation of naturally occurring monoterpenes into amines through rhodium-catalyzed hydroaminomethylation
Melo, Daniela S.,Pereira-Júnior, Schubert S.,Dos Santos, Eduardo N.
experimental part, p. 70 - 76 (2012/03/22)
The hydroaminomethylation (hydroformylation/reductive amination) of the naturally occurring monoterpenes, i.e., limonene, camphene, and β-pinene, was studied having as condensation counterparts the amines di-n-butylamine, morpholine or n-butylamine. Moderate to good yields (75-94%) were obtained employing [Rh(cod)(μ-OMe)]2 as pre-catalyst in the presence or not of triphenylphosphine or tribenzylphosphine as ancillaries in toluene, at 100 °C and 60 bar of an equimolar mixture of carbon monoxide and hydrogen. Some of the hydroaminomethylation products derived from limonene have biological activity and the products derived from camphene and β-pinene are new.
The First Stereoselective Palladium-Catalyzed Cyclocarbonylation of β,γ-Substituted Allylic Alcohols
Brunner, Melanie,Alper, Howard
, p. 7565 - 7568 (2007/10/03)
β,γ-Substituted allylic alcohols react with CO in the presence of catalytic quantities of palladium acetate and 1,4-bis(diphenylphosphino)butane affording α,β-substituted-γ-butyrolactones in 42-85% isolated yields. The complete stereoselectivity observed
Medium- and sensitizer-dependent radical cation reactions: Deprotonation in fluid solution and solid matrices
Roth, Heinz D.,Weng, Hengxin,Zhou, Dahui,Lakkaraju, Prasad S.
, p. 626 - 635 (2007/10/03)
Radical cations generated by photo-induced electron transfer in solution or by chemical oxidation in the channels of a redox-active zeolite (NaZSM-5) may be deprotonated, giving rise to neutral radicals. In solution, the geminate radical anion or an added nucleophile (methanol) may serve as the proton acceptor. Deprotonations in solution are not efficient; the corresponding products may be suppressed by several competing intra- or bi-molecular reactions. Although methanol serves as the base deprotonating at least one radical cation, it often is more efficient as a nucleophile, thereby depressing deprotonation. Deprotonations in the zeolite are more effective, presumably, because competing reactions with outside reagents are precluded. Occasionally, NaZSM-5 zeolites promote complex reaction sequences, such as the conversion of p-propylanisole to the radical cation of anethole or the deprotonation-ring opening of 1,2-diphenylcyclopropane radical cation to exo,exo-diphenylallyl radical. Acta Chemica Scandinavica 1997.
