Addition Reaction Of Alcohols Research Articles

The addition reaction of alcohols and aromatic carbodiimides and its application to produce thermo-reversible polymer networks

The addition reaction of primary alcohols onto aromatic carbodiimides giving iso-ureas was studied in bulk at various temperatures. A side reaction at 60 °C was found to occur between carbodiimide and iso-urea yielding N,N′-substituted polyguanidine oligomers. The occurrence of this side reaction coincides with a reduced conversion of the alcohol; the carbodiimide was always fully converted to either iso-urea or polyguanidine. The formation of the polyguanidine was reversible at higher temperatures to reform iso-urea and carbodiimide. The latter reaction was complete at about 130 °C. The thermo-reversibility of the guanidine bond was utilized to produce thermo-reversible self-healing polymer networks by reaction of polyether diol and a 1.5 to 2-fold molar excess of aromatic biscarbodiimide. The materials were soft and elastic and showed a glass transition at −60 °C. The guanidine linkages in the polymers started to unzip above 60 °C as was indicated by a drop in the E-modulus, at about 130 °C sufficient guanidine crosslinks had unzipped to provide the polymer liquid-like properties. The guanidine crosslinks were reformed after cooling to ambient temperature giving back the polymer network.

Addition Reaction of Alcohol to Isocyanate Catalyzed by Copper Present in Tap Water: Robust Manufacturing Process of Naldemedine Tosylate

Addition Reaction of Alcohol to Isocyanate Catalyzed by Copper Present in Tap Water: Robust Manufacturing Process of Naldemedine Tosylate

Enantioselective Protonation of Cyclic Carbonyl Ylides by Chiral Lewis Acid Assisted Alcohols.

Chiral Lewis acid-catalyzed asymmetric alcohol addition reactions to cyclic carbonyl ylides generated from N-(α-diazocarbonyl)-2-oxazolidinones featuring a dual catalytic system are reported. Construction of a chiral quaternary heteroatom-substituted carbon center was accomplished in which the unique heterobicycles were obtained in good yields with high stereoselection. The alcohol adducts were successfully converted to optically active oxazolidine-2,4-diones by hydrolysis. Mechanistic studies by DFT calculations revealed that alcohols could be activated by Lewis acids, enabling enantioselective protonation of the carbonyl ylides.

Synthesis of β-Phenethyl Ethers by Base-Catalyzed Alcohol Addition Reactions to Aryl Alkenes

The direct anti-Markovnikov addition of alcohols to styrene derivatives represents a streamlined route to β-phenethyl ethers, a substructure frequently found in pharmaceuticals and other bioactive ­molecules. Here, we discuss how the development of such a reaction can complement and address limitations of current methods for β-phenethyl ether synthesis. In particular, we highlight our recent ­approach toward achieving this challenging alcohol addition reaction through P4-t-Bu superbase catalysis. A summary of compatible aryl alkenes and alcohols is provided to inform readers of potential applications of this new catalytic transformation, as well as its current limitations and future directions.1 Introduction2 Anti-Markovnikov Alcohol Addition to Aryl Alkenes: Background3 Superbase-Catalyzed Alcohol Addition to Aryl Alkenes4 Summary and Outlook

Y(OTf)3-catalyzed addition reaction of alcohol to β-nitrostyrene

A concise and efficient addition reaction of alcohol to β-nitrostyrene promoted by Y(OTf)3 has been established for the synthesis of β-nitroether derivatives. The present approach shows attractive properties, such as the high efficiency of catalyst, operational simplicity, and the tolerance of a wide range of functional groups. This strategy not only provides a variety of β-nitroethers but also expands the scope of application of early transition metals.

A mechanistic study of the addition of alcohol to a five-membered ring silene via a photochemical reaction.

The mechanism for the photochemical rearrangement of a cyclic divinyldisilane (1-Si) in its first excited state ((1)π → (1)π*) is determined using the CAS/6-311G(d) and MP2-CAS/6-311++G(3df,3pd) levels of theory. The photoproduct, a cyclic silene, reacts with various alcohols to yield a mixture of cis- and trans- adducts. The two reaction pathways are denoted as the cis- addition path (path A) and the trans-addition path (path B). These model studies demonstrate that conical intersections play a crucial role in the photo-rearrangements of cyclic divinyldisilanes. The theoretical evidence also demonstrates that the addition of alcohol to a cyclic divinyldisilane follows the reaction path: cyclic divinyldisilane → Franck-Condon region → conical intersection → photoproduct (cyclic silene) → local intermediate (with alcohol) → transition state → cis- or trans-adduct. The theoretical studies demonstrate that the steric effects as well as the concentrations of CH3OH must have a dominant role in determining the yields of the final adducts by stereochemistry. The same mechanism for the carbon derivative (1-C) is also considered in this work. However, the theoretical results indicate that 1-C does not undergo a methanol addition reaction via the photochemical reaction pathway, since its energy of conical intersection (S1/S0-CI-C) is more than that of its FC (FC-C). The reason for these phenomena could be that the atomic radius of carbon is much smaller than that of silicon (77 and 117 pm, respectively). As a result, the conformation for 1-C is more sterically congested than that for 1-Si, along the 1,3-silyl-migration pathway.

Lewis Acid-catalyzed Ring-opening Addition Reactions of Alcohols to Vinylcyclopropane

Abstract Lewis acids such as Sn(OTf)2, GaCl3, Sc(OTf)3, and Al(OTf)3 catalyzed ring-opening 1,5-addition reactions of aliphatic alcohols to dimethyl 2-vinylcyclopropane-1,1-dicarboxylate, resulting in moderate to high yields of methyl 4-alkoxy-2-methoxycarbonyl-5-hexenoates with a catalytic turnover number of up to 80. A deuterium-labeling experiment and comparison with the reactivity of dimethyl cyclopropane-1,1-dicarboxylate suggested that this reaction involves a 1,3-dipole intermediate stabilized by the donor and the acceptor substituents. The ring-opening addition of phenols demonstrated several reaction modes, including Friedel–Crafts 1,5- and 1,7-additions.

ChemInform Abstract: A Metal—Ligand Cooperative Pathway for Intermolecular Oxa‐Michael Additions to Unsaturated Nitriles.

ChemInformVolume 46, Issue 31 Preparative Organic Chemistry ChemInform Abstract: A Metal—Ligand Cooperative Pathway for Intermolecular Oxa-Michael Additions to Unsaturated Nitriles. Sebastien Perdriau, Sebastien Perdriau Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorDouwe S. Zijlstra, Douwe S. Zijlstra Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorHero J. Heeres, Hero J. Heeres Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorJohannes G. de Vries, Johannes G. de Vries Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorEdwin Otten, Edwin Otten Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this author Sebastien Perdriau, Sebastien Perdriau Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorDouwe S. Zijlstra, Douwe S. Zijlstra Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorHero J. Heeres, Hero J. Heeres Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorJohannes G. de Vries, Johannes G. de Vries Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this authorEdwin Otten, Edwin Otten Stratingh Inst. Chem., Univ. Groningen, NL-9747 AG Groningen, Neth.Search for more papers by this author First published: 16 July 2015 https://doi.org/10.1002/chin.201531033Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume46, Issue31August, 2015 RelatedInformation

A metal-ligand cooperative pathway for intermolecular oxa-Michael additions to unsaturated nitriles.

An unprecedented catalytic pathway for oxa-Michael addition reactions of alcohols to unsaturated nitriles has been revealed using a PNN pincer ruthenium catalyst with a dearomatized pyridine backbone. The isolation of a catalytically competent Ru-dieneamido complex from the reaction between the Ru catalyst and pentenenitrile in combination with DFT calculations supports a mechanism in which activation of the nitrile through metal-ligand cooperativity is a key step. The nitrile-derived Ru-N moiety is sufficiently Brønsted basic to activate the alcohol and initiate conjugate addition of the alkoxide to the α,β-unsaturated fragment. This reaction proceeds in a concerted manner and involves a six-membered transition state. These features allow the reaction to proceed at ambient temperature in the absence of external base.

A Metal–Ligand Cooperative Pathway for Intermolecular Oxa‐Michael Additions to Unsaturated Nitriles

AbstractAn unprecedented catalytic pathway for oxa‐Michael addition reactions of alcohols to unsaturated nitriles has been revealed using a PNN pincer ruthenium catalyst with a dearomatized pyridine backbone. The isolation of a catalytically competent Ru–dieneamido complex from the reaction between the Ru catalyst and pentenenitrile in combination with DFT calculations supports a mechanism in which activation of the nitrile through metal–ligand cooperativity is a key step. The nitrile‐derived Ru‐N moiety is sufficiently Brønsted basic to activate the alcohol and initiate conjugate addition of the alkoxide to the α,β‐unsaturated fragment. This reaction proceeds in a concerted manner and involves a six‐membered transition state. These features allow the reaction to proceed at ambient temperature in the absence of external base.

Synthesis of functionalized cyclotriveratrylene analogues with C1-symmetry and the application for 1,4-Michael addition of alcohols to unsaturated aryl ketone

C1-symmetric cyclotriveratrylene analogues 2–8 with various functional groups at one benzene moiety were prepared starting from the selectively demethylated compound 1. Through the chemical resolution, a pair of enantiomers of C1-symmeric compound 1 could be separated with gram scale. Compound 8, which possessed an N-linked imidazolium unit at the upper rim of the macrocyclic skeleton through a methylene linker, was successfully applied to 1,4-Michael addition reaction of alcohol to unsaturated aryl ketone. Its supramolecular catalytic activity as an NHC precursor was demonstrated by the chem-selectivity to aromatic alcohol than alkyl alcohol.

Foundations of organic chemistry: unity and diversity of structures, pathways, and reactions

Foundations of organic chemistry: unity and diversity of structures, pathways, and reactions

The ionic liquid ethyltri- n-butylphosphonium tosylate as solvent for the acid-catalysed hetero-Michael reaction

A new and convenient method for the acid-catalysed Michael addition reactions of alcohols, thiols and amines to methyl vinyl ketone has been developed using the ionic liquid ethyltri- n-butylphosphonium tosylate. The reaction conditions are mild and obviate the need for toxic and expensive Lewis acid catalysts, offering advantages over more commonly used systems.

Studies on the Total Synthesis of Lactonamycin: Construction of Model ABCD Ring Systems

Model studies on the synthesis of the tetracyclic ABCD ring system of lactonamycin (1) are described. The key step involved the double Michael addition reaction of alcohol 8 to propynoate esters to produce the BCD units 13 and 14 of the target 1. Alternatively, double Michael addition of alcohol 8 to di-tert-butyl acetylenedcarboxylate gave the corresponding BCD ring systems 36 and 37. Acid-mediated hydrolysis of the dihydroquinone monoketal units of 13 and 14 and 36 and 37 in the presence of air gave the corresponding quinones 7 and 39. These were converted into the tetracyclic ABCD units 6, 26a, 40, and 42 of lactonamycin (1) by either dihydroxylation or epoxidation and acid-catalyzed lactonization.

Ruthenium‐Catalyzed Addition Reaction of Alcohols Across Olefins.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Ruthenium-Catalyzed Addition Reaction of Alcohols across Olefins

2-Phenylethanol was added to olefins catalyzed by ruthenium catalytic system Cp*RuCl2(PPh3)/2AgOTf in toluene. This ­reaction proceeded without β-hydride elimination, giving saturated ethers in good yields.

Gas−Phase Hydration and Alcohol Addition Reactions of Complexes Composed of Ag+ and a Single Alcohol Molecule

The reactivity of mono-alcohol/Ag+ complexes (methanol, ethanol, n-propanol, n-butanol, and tert-butyl alcohol) when stored, without collisional activation, in an ion trap mass spectrometer for periods ranging from 1 to 1000 ms was investigated. During the isolation/reaction time, association reactions between the complex ions and adventitious water and alcohol present within a He bath gas occurred to varying degrees. While the free Ag+ ion was unreactive, complexes composed of Ag+ coordinated by a single alcohol molecule demonstrated reactivity consistent with the following reactions: (1) formation of an adduct by the addition of a single water molecule, (2) formation of a bis-alcohol complex by the addition of a second alcohol molecule, and (3) formation of the bis-alcohol complex via the exchange of a water molecule for alcohol when investigated under similar experimental conditions. The trend in reactivity followed the order n-butanol > n-propanol > ethanol > methanol. To quantify observed trends in hydration reactivity, experimental kinetic plots were modeled stochastically. Reasonable fits to experimental reaction kinetic plots were achieved using a model that included forward and, in some cases, apparently reverse reactions, consistent with the addition of either water or alcohol in nondissociative fashion. Pseudo-first-order reaction rate constants were generated using stochastic kinetic simulations that provide insight into the relative reactivity of the mono-alcohol/Ag+ complexes. To rationalize the observed trends in reactivity, the lowest energy conformations and molecular orbital geometries were determined using Hartree−Fock and density functional theory calculations. Our results show that the hydration and alcohol addition reactivity of Ag+ may be influenced by the degree to which electron density can be delocalized within a coordinating ligand and to which the electron density within a hybridized orbital on Ag+ is decreased by bonding to an alcohol molecule.

Selective synthesis of fluorinated ethers by addition reaction of alcohols to fluorinated olefins in water

The green process for the preparation of fluorinated ether by the addition reaction of 2,2,2-trifluoroethanol to fluorinated olefins was examined. The selective synthesis of fluorinated ether was achieved by increasing the amount of the proton source in the reaction. The reaction with water as the proton source was a particularly environmentally friendly process, because a highly selective synthesis was achieved by means of a completely organic solvent-free procedure. Also, it allowed for a simple work-up, and a scaling up was easily performed.

Absolute Reactivity of the 4-Methoxycumyl Cation in Non-Acid Zeolites

The reactivity of the 4-methoxycumyl cation in a series of alkali metal cation-exchanged zeolites (LiY, NaY, KY, RbY CsY, NaX, NaMor, and Naβ) in the absence and presence of coadsorbed alcohols and water is examined using nanosecond laser flash photolysis. In dry zeolites, the absolute reactivity of the carbocation is found to be strongly dependent on the nature of the alkali counterion, the Si/Al ratio, and the framework morphology, with the lifetime of the carbocation in Naβ being almost 10000-fold longer than in CsY. The results suggest a mechanism for carbocation decay involving direct participation of the zeolite framework as a nucleophile, leading to the generation of a framework-bound alkoxy species. Intrazeolite addition reactions of alcohols and water to the 4-methoxycumyl cation can be described in terms of both dynamic and static quenching involving molecular diffusion through the heterogeneous topology and rapid coupling between the alcohol and the carbocation encapsulated within the same cavity. The dynamics of the quenching reactions are different from similar reactions in homogeneous solution due to both the passive and active influences of the zeolite environment. In a passive sense, the zeolite decreases the reactivity of the nucleophilic quencher by hindering molecular diffusion. However, the zeolite actively promotes the efficiency of intracavity coupling by enhancing the deprotonation of the oxonium ion intermediate, allowing the reaction to go to completion.

Transferring iodine: more than a simple functional group exchange in organic synthesis

Abstract