Conversion Of Primary Alcohols Research Articles

Catalytic Appel Reaction Accessing the Mesoporous Substructure of a Robust and Heterogeneous Polyphosphamide

AbstractPolyphosphamides are normally good flame retardants. Herein a mesoporous polyphosphamide (p‐PPA) with an accessible average pore diameter of <10 nm and a surface area of 1.773 m2/g has been synthesized via condensation of 1,3‐diamino benzene (DAB) and phenyl phosphinic dichloride (PPDC). 31P, 13C CP‐MAS solid‐state NMR, Raman, and X‐ray photoelectron spectroscopic (XPS) characterizations confirm the presence of ‐{PV(O)‐NH}‐ in the repeating unit of the p‐PPA that is further used as a catalytic mediator to perform the Appel reaction i. e., conversion of alcohols to halides with a broad substrate scope and high TON (561). The heterogeneity of p‐PPA allows easy recovery of organic halides and recycling of the catalyst many times. Mesoporous p‐PPA has further given a scope to perform shape‐selective conversion of primary alcohols with linear alkyl chain (1‐dodecanol) while a low conversion for the bulky secondary (cyclo‐hexanol) and tertiary alcohol (tert‐butanol) is observed. Perhaps, the phosphamide units present inside the porous channel are non‐preferable sites for bulkier alcohols, as evident from the competitive experiments. A comparatively less catalytic conversion obtained with an analogous non‐porous n‐PPA, made of tris(2‐aminoethyl)amine (TREN) linker, highlights the role of porosity in p‐PPA to enhance the accessibility of numerous ‐{PV(O)‐NH}‐ reactive units to increase the TON.

Conversion of Primary Alcohols and Butadiene to Branched Ketones via Merged Transfer Hydrogenative Carbonyl Addition-Redox Isomerization Catalyzed by Rhodium.

The first examples of rhodium-catalyzed carbonyl addition via hydrogen autotransfer are described, as illustrated in tandem butadiene-mediated carbonyl addition-redox isomerizations that directly convert primary alcohols to isobutyl ketones. Related reductive coupling-redox isomerizations of aldehyde reactants mediated by sodium formate also are reported. A double-labeling crossover experiment reveals that the rhodium alkoxide obtained upon carbonyl addition enacts redox isomerization without dissociation of rhodium at any intervening stage.

Rational Low‐Temperature Synthesis of Ultrasmall Nanocrystalline Manganese Binary Oxide Catalysts under Controlled Metal Cation Hydration in Organic Media

AbstractUltrasmall nanocrystalline manganese binary oxides with various compositions and crystal structures were synthesized by a convenient, rational low‐temperature method. These oxides were obtained in 2‐propanol‐based solutions using the organic‐solvent‐soluble MnO4− as a manganese source under controlled metal cation template hydration. Three‐dimensional spinel oxides were generated selectively by suppressing the hydration of metal cation templates. One‐dimensional tunnels and two‐dimensional layered structures predominated under adequate and high hydration, respectively. These oxides acted as efficient reusable heterogeneous catalysts for primary alcohol ammoxidation and amidation using aqueous NH3 as a nitrogen source and O2 (air) as a terminal oxidant. In particular, ultrasmall Co−Mn spinel oxide effectively catalyzed the ammoxidation of primary alcohols into their corresponding nitriles. The Li−Mn spinel oxide promoted the hydration of ammoxidation‐derived nitriles, facilitating the one‐pot conversion of primary alcohols into primary amides.

Chlorodiphenylphosphine as Highly Selective and Efficient Reagent for the Conversion of Alcohols, Tetrahydropyranyl and Silyl Ethers to Thiocyanates and Isothiocyanates

A simple, highly selective and efficient method is described for the conversion of primary alcohols, tetrahydropyranyl and silyl ethers to thiocyanates by use of chlorodiphenylphosphine and ammonium thiocyanate. Secondary substrates produce both the two isomeric products, thiocyanate and isothiocyanate, while tertiary ones give isothiocyanates as the only products by this new method. In contrast to previously reported methods based on trivalent phosphorus for this transformation, the present method does not require an electrophile in the presence of trivalent phosphorus (ClPPh2). The order of activity of these substrates is silyl ether> alcohol > tetrahydropyranyl ether. The present method not only interestingly distinguishes between primary, secondary and tertiary substrates but also converts them to the corresponding thiocyanates with excellent chemoselectivity in the presence of several other functional groups.

Iron-catalyzed oxidative synthesis of N-heterocycles from primary alcohols

An iron-catalyzed one-pot one-step oxidative system has been successfully developed in the conversion of primary alcohols into nitrogen-containing heterocycles, such as quinazolinone, quinazoline and 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxide derivatives.

Ruthenium-Catalyzed Self-Coupling of Primary and Secondary Alcohols with the Liberation of Dihydrogen

The dehydrogenative self-condensation of primary and secondary alcohols has been studied in the presence of RuCl2(IiPr)(p-cymene). The conversion of primary alcohols into esters has been further optimized by using magnesium nitride as an additive, which allows the reaction to take place at a temperature and catalyst loading lower than those described previously. Secondary alcohols were dimerized into racemic ketones by a dehydrogenative Guerbet reaction with potassium hydroxide as the additive. The transformation gave good yields of the ketone dimers with a range of alkan-2-ols, whereas more substituted secondary alcohols were unreactive. The reaction proceeds by dehydrogenation to the ketone, followed by an aldol reaction and hydrogenation of the resulting enone.

Solvent‐free cyanoethylation of selected alcohols using amberlyst A‐21 polymer resin

AbstractSolvent‐free cyanoethylation of selected alcohols with acrylonitrile (AN) using a weakly basic polymer resin, Amberlyst A‐21 (AA‐21) was studied at 75°C. The conversion of primary alcohols, 1‐octadecanol, hexane‐1,6‐diol, pentaerythritol, but‐2‐yne‐1,4‐diol, N‐methyldiethanolamine, triethanolamine and diethanolamine is higher than secondary alcohols, isopropanol and glycerol in the presence of polymer resin. Of various alcohols, but‐2‐yne‐1,4‐diol gave the product in high conversion (87%) in cyanoethylation with a polymer resin/AN weight ratio of 0.04. The polymer resin showed recycling ability only in two cycles to produce cyanoethylated product from diethanolamine. In case of 1‐octadecanol, hexane‐1,6‐diol, and N‐methyldiethanolamine with AN under similar conditions, no recycling ability was observed. Thermally treated polymer resin at 75°C afforded the product in lower conversion (55%) whereas the same product was obtained in 69% when fresh polymer resin was used in cyanoethylation of 1‐octadecanol. No catalytic effect was observed for polymer resin treated at 100°C. Fourier transform infrared (FTIR) spectra showed CN stretching at 2248 cm−1 for the polymer resin collected after the reaction which was caused by the AN binding on polymer resin during the reaction. As per thermogravimetric curves, 5% weight loss was observed at 201°C for recovered resin and at 161°C for polymer resin treated at 100°C. Scanning electron microscope images confirmed the AN binding on polymer beads after catalytic activity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

ChemInform Abstract: TPAP‐Catalyzed Direct Oxidation of Primary Alcohols to Carboxylic Acids Through Stabilized Aldehyde Hydrates.

AbstractThe intermediary aldehyde hydrate is stabilized by N‐oxides, especially NMO.

Cyanuric chloride/dimethylformamide promoted one-pot conversion of primary alcohols into alkyl thiocyanates

A convenient and efficient procedure for one-pot conversion of alcohols into corresponding alkyl thiocyanates in the presence of cyanuric chloride/dimethylformamide mixed reagent is described. This approach is efficient and selective for primary alcohols especially substituted benzyl alcohols. This method can be easily applied for the facile conversion of primary alcohols into corresponding thiocyanates, but sterically hindered alcohols produced corresponding thiocyanates in very low yields.

ChemInform Abstract: Conversion of Primary Alcohols and Aldehydes into Methyl Esters by Ruthenium‐Catalyzed Hydrogen Transfer Reactions.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Conversion of Primary Alcohols and Aldehydes into Methyl Esters by Ruthenium-Catalysed Hydrogen Transfer Reactions

Alcohols and aldehydes are oxidised to the corresponding methyl esters by reaction with methanol in the presence of crotono-nitrile as a hydrogen acceptor using a catalyst combination of Ru(PPh 3 ) 3 (CO)H 2 with xantphos.

Alumina Sulfuric Acid as an Efficient and Recyclable Heterogeneous Catalyst for the O-Silylation of Alcohols, Phenols, and Oximes

Alumina sulfuric acid as a recyclable catalyst conducts the transformation of various types of alcohol, phenols, and oximes with hexamethyldisilazane (HMDS) to the corresponding O-trimethylsilylated compounds in good to excellent yields under mild and ambient conditions with short reaction times. The method is highly selective for the conversion of primary alcohols in the presence of secondary and tertiary alcohols. Additionally, the catalyst can be easily recovered and reused at least eight times without detectable loss of reactivity.

A New and Efficient Method for the Protection of Alcohols and Phenols by Using Hexamethyldisilazane in the Presence of Anhydrous Ferric Chloride under Mild Reaction Conditions

Alcohols and phenols are protected with hexamethyldisilazane in the presence of anhydrous ferric chloride in good to excellent yields in acetonitrile. This method is highly selective for the conversion of primary alcohols in the presence of secondary and tertiary alcohols and also for conversion phenols.

A Novel and highly selective conversion of alcohols, thiols, and silyl ethers to azides using the 2,4,6-trichloro[1,3,5]triazine/n-Bu4NN3 system

Alkyl azides are prepared in good to excellent yields by treatment of alcohols, thiols and trimethylsilyl ethers with 2,4,6-trichloro[1,3,5]triazine/n-Bu4NN 3 in acetonitrile. This method is highly selective for conversion of primary alcohols to alkyl azides in the presence of secondary and tertiary alcohols, thiols and trimethysilyl ethers.

Direct Oxidative Conversion of Primary Alcohols to Nitriles Using Molecular Iodine in Ammonia Water.

A simple, effective, high-yield procedure for the direct oxidative conversion of alcohols to nitriles, was successfully carried out with molecular iodine in ammonia water.

IBX‐Mediated Conversion of Primary Alcohols and Aldehydes to N‐Hydroxysuccinimide Esters.

Recently, the use of the hypervalent iodine reagent 1-hydroxy-1,2-benziodoxol-3(1H)-one 1-oxide (IBX) for the oxidation of primary alcohols and aldehydes to carboxylic acids was described. During the synthesis of these carboxylic acids the corresponding N-hydroxysuccinimide esters were formed as intermediate products, but their isolation as main reaction products was not successful. We report herein a simple and very efficient method to prepare these synthetically valuable active esters.

IBX‐Mediated Conversion of Primary Alcohols and Aldehydes to N‐Hydroxysuccinimide Esters

AbstractRecently, the use of the hypervalent iodine reagent 1‐hydroxy‐1,2‐benziodoxol‐3(1H)‐one 1‐oxide (IBX) for the oxidation of primary alcohols and aldehydes to carboxylic acids was described. During the synthesis of these carboxylic acids the corresponding N‐hydroxysuccinimide esters were formed as intermediate products, but their isolation as main reaction products was not successful. We report herein a simple and very efficient method to prepare these synthetically valuable active esters.

Tandem Oxidation Processes: The Direct Conversion of Activated Alcohols into Esters and Amides

The direct conversion of primary alcohols into methyl esters and amides using manganese dioxide and sodium cyanide with methanol or the appropriate amine is reported. These transformations, which proceed via an in situ four step, double oxidation sequence, have been applied to a range of benzylic, heterocyclic, allylic and propargylic alcohols.

One-pot conversion of primary alcohols to α-oxygenated alkanals with TEMPO in combination with molecular oxygen and ruthenium complex

One-pot conversion of primary alcohols to α-oxygenated alkanals with TEMPO in combination with molecular oxygen and ruthenium complex

ChemInform Abstract: Mild Conversion of Primary Alcohols (I) and Aldehydes (III) to Acid Fluorides (II), (IV) with Cesium Fluoroxysulfate.

ChemInform Abstract: Mild Conversion of Primary Alcohols (I) and Aldehydes (III) to Acid Fluorides (II), (IV) with Cesium Fluoroxysulfate.