Reaction Of Allylic Alcohols Research Articles

Investigation of the Properties of Unsaturated Allyl Alcohol and its Oxidation Reaction Products

Abstract Organic substances in which the -OH group is directly attached to the carbon atom are called alcohols. Unsaturated alcohols are obtained by replacing the hydrogen of ethylene or acetylene-type compounds with a hydroxyl group. Allyl alcohol, the first representative of the class of unsaturated alcohols, contains oxygen. Allyl alcohol is used in optical resins, protective glasses, paints and coatings and polymer cross-linking agents, as well as in the production of pharmaceuticals, organic chemicals, plastics, herbicides, and pesticides. In organic chemistry, alcohols can be oxidized to aldehydes, ketones, carboxylic acids, and esters that carry a higher oxidation state of carbon. Therefore, the selective oxidation of alcohols is an important issue. The properties and selective oxidation reaction of allyl alcohol were investigated in the presented work.

Ruthenium‐Catalysed Asymmetric Intramolecular Isomerization/Esterification Reaction: Direct Synthesis of Chiral Dihydrocoumarins

Comprehensive SummaryAn asymmetric isomerization/intramolecular coupling reaction of allylic alcohols to synthesize chiral dihydrocoumarins was successfully accomplished through ruthenium catalysis. This method demonstrates a wide substrate applicability, excellent tolerance for various functional groups, and good enantioselectivities (up to 90% ee). It provides a convenient pathway to produce a diverse range of structurally distinct chiral dihydrocoumarins in good efficiency.

Naturally occurring phytic acid: an advanced Brønsted acid catalyst for direct amination reactions of allylic alcohols.

Phytic acid is abundant in various plant-based foods and is considered agricultural waste. Here, we demonstrate the effectiveness of this organophosphorus acid as a sustainable catalyst for the direct amination reactions of allylic alcohols. This approach is successfully performed in air using technical grade solvents, affording allylanilines in moderate to excellent yields. Challenging electron-rich anilines react effectively, and their corresponding Friedel-Crafts side products can be minimised under the optimised reaction conditions. A variety of asymmetrically substituted allylic alcohols are tolerated, while the scope is extended to amide, and C-, O- and S-nucleophiles.

Titanium-Mediated Dehydroxylative Cross-Coupling of Allylic Alcohols with Electron-Deficient Olefins.

Herein we report a Ti(III)-mediated dehydroxylative cross-coupling reaction of allylic alcohols with electron-deficient olefins. This reaction is amenable to various synthetically versatile allylic alcohols, including geraniol and farnesol, providing a general method for dehydroxylative C-C bond formation. We demonstrated the reaction's utility by simplifying the syntheses of eight useful building blocks that are otherwise laborious to prepare.

Nickel-Catalyzed Ligand-Controlled Regioselective Allylic Alkenylation of Allylic Alcohols with Easily Accessible Alkenyl Boronates: Synthesis of 1,4-Dienes.

A nickel-catalyzed direct reaction of allylic alcohols with easily accessible alkenyl boronates has been developed, which provides valuable 1,4-dienes with high regio- and stereoselectivity in good to excellent yields, wide substrate scope, and functional group compatibility. The catalytic system simply consists of Ni(cod)2 as the catalyst and a ligand, without a need for a base and alcohol activator in most cases. The proper choice of ancillary ligands is highly important for this reaction. Depending on the substitution pattern of allylic alcohols and/or alkenyl boronates, different ligands were used for improving the reaction efficiency.

P-Cresol-Enabled Nickel-Catalyzed Intermolecular Redox-Economical Coupling of Allyl Alcohols with Alkynes through oxa-Nickelacycle.

An intermolecular redox-economical coupling reaction of allyl alcohols with alkynes, catalyzed by Ni-Brønsted acid cocatalysis, has been developed. This method allows for the synthesis of a diverse range of γ,δ-unsaturated ketones with yields ranging from 40% to 94%, while maintaining excellent compatibility with various functional groups. The transformation of the resulting product demonstrates the significant practical value of this method. Further mechanistic investigations have revealed that the reaction proceeds through the formation of an oxa-nickelacycle intermediate.

Stereoselective Synthesis of Heavily Hydroxylated Azepane Iminosugars via Osmium-Catalyzed Tethered Aminohydroxylation.

A novel stereoselective synthetic approach to pentahydroxyazepane iminosugars is described. The strategy relies on a key osmium-catalyzed aminohydroxylation reaction of allylic alcohols obtained via addition of vinylmagnesium bromide to a d-mannose-derived aldehyde, which forms the new C-N bond with complete regio- and stereocontrol according to the tethering approach. Subsequent intramolecular reductive amination afforded the desired azepanes. This method represents the first application of the osmium-catalyzed tethered aminohydroxylation reaction to the synthesis of iminosugars.

Pd‐Catalyzed Dehydrative Synthesis of Allylic Amines in Water

AbstractA mild Pd‐catalyzed Tsuji‐Trost reaction of allylic alcohols with an amine nucleophile in water media was developed, leading to the green synthesis of the valuable allylic amines. This new method requires no chemical activators and sophisticated soluble ligands, and can be easily scaled up in gram scale and be readily extended to the gram scale synthesis of Naftifine, one of the best‐selling antifungal drugs, showing the practical value of this new method.

Reductive Deoxygenative Functionalization of Alcohols by First‐Row Transition Metal Catalysis

Comprehensive SummaryAlcohols are among the most accessible functionalities. Catalytic deoxygenative functionalization of alcohols is highly synthetically appealing. While significant progress has been made on the reactions with nucleophiles, the reactions with electrophilic coupling partners remain a real challenge. This manuscript highlights the advance in this direction, which is mainly achieved by the first‐row transition metals. The low‐valent titanium catalyst has shown the unique reactivity to homolytically cleave the C—OH bonds. The formed carbon radicals could either undergo reduction to give protonation products or couple with carbon fragments to form C—C bonds. This chemistry is initially realized using a stoichiometric amount of titanium reagents and later extended to catalytic variants. Nickel features a variety of oxidation states ranging from Ni0 to NiIV, and both two‐electron oxidative addition and single‐electron process are involved in their activation of an electrophile. These properties enable nickel to catalyze reductive C—C coupling of alcohols with R–X electrophiles. The reaction is first reported on the reactions of allylic alcohols, then extended to benzylic alcohols and, very recently non‐activated alcohols. Recent effort has resulted in many invaluable methodologies that highly improve the reaction efficiency for the construction of aliphatic C—C bonds. The use of cobalt and copper catalysts not only expands the substrate scope of these reactions but also shows the new reactivity and selectivity issues.

Oxovanadium(V)‐Catalyzed Deoxygenative Coupling Reaction of Alcohols with Trimethylsilyl Enol Ethers in the Presence of MS3A

AbstractOxovanadium(V)‐catalyzed deoxygenative coupling reaction of allyl alcohols with trimethylsilyl enol ethers was demonstrated to afford γ,δ‐unsaturated carbonyl compounds in one‐step. The catalytic deoxygenative coupling reaction of allyl alcohols proceeded smoothly with both aromatic and aliphatic trimethylsilyl enol ethers. This catalytic deoxygenative coupling system could be applied to the deoxygenative coupling reaction of benzyl alcohols with trimethylsilyl enol ethers, providing the corresponding carbonyl compounds. Furthermore, a gram‐scale catalytic synthesis of the γ,δ‐unsaturated carbonyl compound was successfully performed to validate the scalability of this catalytic deoxygenative coupling reaction.

Nickel-Catalyzed Direct Substitution of Allylic Alcohols with Nitriles: A General Tool for the Construction of Acyclic C2-Tertiary or Quaternary Benzyl Nitriles

A nickel-catalyzed direct reaction of allylic alcohols with benzyl nitrile derivatives has been developed. The method provides an efficient route for the synthesis of nitriles bearing an α-tertiary or quaternary carbon center in good to excellent yields with high regioselectivity, wide substrate scope, and functional group compatibility. BSA was identified as the effective additive for facilitating the coupling process mainly for alkyl allylic alcohols.

Стереоселективный синтез аминоспиртов на основе терпинен-4-ола.

Terpinen-4-ol 1, a monoterpene, is found as the main component of essential oils isolated from cassumunar ginger and tea tree, exhibits different biological activities such as anticancer,anti-inflammatory, antibacterial and antiviral. In this paper chemical transformation of terpinen4-ol 1 is investigated with the aim to synthesize its new derivatives for the further application aspotential candidates in drug discovery. Stereoselective synthesis of aminodiols 3-6 derived fromterpinen-4-ol 1 was achieved with good yields. Two steps procedure of chemical transformation ofterpinen-4-ol 1 to aminodiols 3-6 were performed by the stereoselective Payne epoxidation reactionof allyl alcohol 1 followed by the regioselective lithium perchlorate-catalyzed oxirane ring openingof epoxy alcohol 2 with benzyl amines. Obtained products were characterized by NMR analysisincluding two dimensional measurements.

Triflamidation of Allyl-Containing Substances:Unusual Dehydrobromination vs. Intramolecular Heterocyclization.

Allyl halides with triflamide under oxidative conditions form halogen-substituted amidines. Allyl cyanide reacts with triflamide in acetonitrile or THF solutions in the presence of NBS to give the products of bromotriflamidation with a solvent interception, whereas in CH2Cl2 two regioisomers of the bromotriflamidation product without a solvent interception were obtained. The formed products undergo base-induced dehydrobromination to give linear isomers with the new C=C bond conjugated either with the nitrile group or the amidine moiety or alkoxy group. Under the same conditions, the reaction of allyl alcohol with triflamide gives rise to amidine, which was prepared earlier by the reaction of diallyl formal with triflamide. Unlike their iodo-substituted analogs, bromo-substituted amidines successfully transform into imidazolidines under the action of potassium carbonate.

Carbonylative Cross‐Coupling Reaction of Allylic Alcohols and Organoalanes with 1 atm CO Enabled by Nickel Catalysis

AbstractA nickel‐catalyzed three‐component carbonylative cross‐coupling reaction of allylic alcohols and organoalanes with CO at atmospheric pressure is reported, enabling the expedient formation of β,γ‐unsaturated ketones with broad scope. Particularly, the chemoselective allylic carbonylation of diols further highlights the practicability of this protocol. The leverage of organoalanes as both the coupling components and the activators for the alcohol functionalization is crucial for this method, thus no extraneous activators are required.

Carbonylative Cross-Coupling Reaction of Allylic Alcohols and Organoalanes with 1 atm CO Enabled by Nickel Catalysis.

A nickel-catalyzed three-component carbonylative cross-coupling reaction of allylic alcohols and organoalanes with CO at atmospheric pressure is reported, enabling the expedient formation of β,γ-unsaturated ketones with broad scope. Particularly, the chemoselective allylic carbonylation of diols further highlights the practicability of this protocol. The leverage of organoalanes as both the coupling components and the activators for the alcohol functionalization is crucial for this method, thus no extraneous activators are required.

Reductive Cross-Coupling of Unreactive Electrophiles.

Transition-metal-catalyzed reductive coupling of electrophiles has emerged as a powerful tool for the construction of molecules. While major achievements have been made in the field of cross-couplings between organic halides and pseudohalides, an increasing number of reports demonstrates reactions involving more readily available, low-cost, and stable, but unreactive electrophiles. This account summarizes the recent results in our laboratory focusing on this topic. These findings typically include deoxygenative C-C coupling of alcohols, reductive alkylation of alkenyl acetates, reductive C-Si coupling of chlorosilanes, and reductive C-Ge coupling of chlorogermanes.The reductive deoxygenative coupling of alcohols with electrophiles is synthetically appealing, but the potential of this chemistry remains to be disclosed. Our initial study focused on the reaction of allylic alcohols and aryl bromides by the combination of nickel and Lewis acid catalysis. This method offers a selectivity that is opposite to that of the classic Tsuji-Trost reactions. Further investigation on the reaction of benzylic alcohols led to the foundation of a dynamic kinetic cross-coupling strategy with applications in the nickel-catalyzed reductive arylation of benzylic alcohols and cobalt-catalyzed enantiospecific reductive alkenylation of allylic alcohols. The titanium catalysis was later established to produce carbon radicals directly from unactivated tertiary alcohols via C-OH cleavage. The development of their coupling reactions with carbon fragments delivers new methods for the construction of all-carbon quaternary centers. These reactions have shown high selectivity for the functionalization of tertiary alcohols, leaving primary and secondary alcohols intact. Alkenyl acetates are inexpensive, stable, and environmentally friendly and are considered the most attractive alkenyl reagents. The development of reductive alkylation of alkenyl acetates with benzyl ammoniums and alkyl bromides offers mild approaches for the conversion of ketones into aliphatic alkenes.Extensive studies in this field have enabled us to extend the cross-electrophile coupling from carbon to silicon and germanium chemistry. These reactions harness the ready availability of chlorosilanes and chlorogermanes but suffer from the challenge of their low reactivity toward transition metals. Under reductive nickel catalysis, a broad range of alkenyl and aryl electrophiles couple well with vinyl- and hydrochlorosilanes. The use of alkyl halides as coupling partners led to the formation of functionalized alkylsilanes. The C-Ge coupling seems less substrate-dependent, and various common chlorogermanes couple well with aryl, alkenyl, and alkyl electrophiles. In general, functionalities such as Grignard-sensitive groups (e.g., acid, amide, alcohol, ketone, and ester), acid-sensitive groups (e.g., ketal and THP protection), alkyl fluoride and chloride, aryl bromide, alkyl tosylate and mesylate, silyl ether, and amine are tolerated. These methods provide new access to organosilicon and organogermanium compounds, some of which are challenging to obtain otherwise.

Bifunctional Oxidation Catalysis of New Titanium-Silicon Molecular Sieve (HTS-1) Based on the Reaction of Allyl Alcohol and Hydrogen Peroxide

The HTS-1 (Hollow Titanium silicalite molecular sieve) catalyst with bifunctional catalysis showed superior catalytic activity in the epoxidation of olefins and the oxidation of alcohols. The competitive oxidation law of enols in the HTS-1/H2O2 oxidation system was studied. The effects of various reaction conditions, such as the reaction temperature, solvent, catalyst type, and the amount of additive, were examined. The results indicated that the HTS-1 catalyst preferentially catalyzes AA epoxidation to produce glycidol (GLY) efficiently and selectively using polar proton solvent and proper temperature. Using alkaline additives can greatly improve the catalytic activity of HTS-1 and selectivity of glycidol. Under optimal conditions, the conversion of AA can rate to 77%, and the selectivity of GLY can also achieve 91%.

Platinum on carbon-catalysed site-selective H–D exchange reaction of allylic alcohols using alkyl amines as a hydrogen source

The platinum on carbon catalysed site-selective H–D exchange reaction of allylic alcohols in the presence of amylamine as a hydrogen source and deuterium oxide as a deuterium source was developed.

Potassium Base-Promoted Diastereoselective Synthesis of 1,3-Diols from Allylic Alcohols and Aldehydes through a Tandem Allylic-Isomerization/Aldol-Tishchenko Reaction.

This study reports the first base-promoted aldol-Tishchenko reactions of allylic alcohols with aldehydes initiated by allylic isomerization. The reaction enables the diastereoselective synthesis of a variety of 1,3-diols with three contiguous stereogenic centers. Unlike commonly reported systems, our method allows the use of readily available allylic alcohols as nucleophiles instead of enolizable aldehydes and ketones.

Cobalt-Catalyzed Enantiospecific Dynamic Kinetic Cross-Electrophile Vinylation of Allylic Alcohols with Vinyl Triflates.

Asymmetric cross-electrophile coupling has emerged as a promising tool for producing chiral molecules; however, the potential of this chemistry with metals other than nickel remains unknown. Herein, we report a cobalt-catalyzed enantiospecific vinylation reaction of allylic alcohol with vinyl triflates. This work establishes a new method for the synthesis of enantioenriched 1,4-dienes. The reaction proceeds through a dynamic kinetic coupling approach, which not only allows for direct functionalization of allylic alcohols but also is essential to achieve high chemoselectivity. The use of cobalt enables the reactions to proceed with high enantiospecificity, which have failed to be realized by nickel catalysts.