Amberlyst-15–Catalyzed Facile Synthesis of α-Amino Phosphonates

A simple and efficient method has been developed for the synthesis of sulfonamide phosphonates from N-tosyl aldimines and dimethyl trimethylsilyl phosphite at 0 °C in the presence of Amberlyst-15 as a heterogeneous catalyst.

Mild Organic Ammonium Tribromide–Mediated Regioselective Ring Opening of Epoxides with Alcohols,Water, Acetic Anhydride,and Amines Under Solvent-Free Reaction Conditions

Organic ammonium tribromide (OATB), N-methylpyrrolidine-2-one hydrotribromide (MPHT) was found to be an efficient catalyst for the regioselective ring opening of epoxides with various nucleophiles under solvent free conditions. This procedure occurs under neutral and mild reaction conditions with out adding any additive and afforded high yields of products.

Deoxygenation of Aromatic Ketones Using Transfer Hydrogenolysis with Raney Nickel in 2-Propanol

Aryl ketones are readily deoxygenated to their corresponding aryl alkanes upon treatment with Raney nickel catalyst in boiling 2-propanol.

Simple and Efficient One-Pot Synthesis of Nitriles from Amides and Oximes Using in Situ–Generated Burgess-Type Reagent

The dehydration of aldoximes and amides, and oxidation of benzoin are accomplished in one-pot using in situ–generated Burgess-type reagent.

One-Pot Efficient Synthesis of Fully Substituted 1,3,4-Oxadiazole Derivatives from (N-Isocyanimino)triphenylphosphorane,Carboxylic Acids,and Aromatic Bis-Aldehydes

Reactions of (N-isocyanimino)triphenylphosphorane with aromatic bis-aldehydes (isophthalaldehyde and terphthalaldehyde) in the presence of aromatic (or heteroaromatic) carboxylic acids proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in good yields. The reaction proceeds smoothly and cleanly under mild conditions, and no side reactions were observed.

Synthesis of Ionic Liquids Containing the Hydroxyl Functionality for Extracting Nonylphenol and Octylphenol in Water

A new series of task-specific ionic liquids (TSILs) containing hydroxyl groups was prepared and applied for extracting 4-nonylphenol (4-NP) and 4-tert-octylphenol (4-t-OP) in water. These new TSILs showed much greater extraction efficiencies for 4-NP and 4-t-OP than the common typical ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate ([C₄mim][PF₆]) and 1-hexyl-3-methylimidazolium hexafluorophosphate ([C₆mim][PF₆]).

Efficient and Selective Demethylation of Heteroaryl Methyl Ethers in the Presence of Aryl Methyl Ethers

A new and efficient method for the demethylation of 6-membered aza-heterocyclic methyl ethers is described using lithium chloride and para-toluenesulfonic acid. This process is chemoselective for aza-heterocyclic methyl ethers in the presence of aryl methyl ethers.

Improved Synthesis of Monoprotected 5- and 6-Amino-2-azanorbornanes

An improved synthesis of Boc-monoprotected 5- and 6-amino-2-azanorbornanes is reported. The synthetic scheme consists of five steps and allows multigram quantities of the title compounds to be obtained. The regio- and stereochemistries of the products are established by two-dimensional NMR experiments.

Simple and Mild One-Pot Synthesis of Dipeptidyl Ureas via Carbamoyl Azides of α-N-Protected Amino Acids

A simple and mild one-pot synthesis of potentially bioactive α-N-protected dipeptidyl ureas is reported. The procedure involves the reaction between the carbamoyl azide of an α-N-protected amino acid and an α-amino acid methyl ester. The reaction is fast (3 h at 45 °C), regardless of the nature of both the reagents, and racemization free. The reported protocol represents a valid alternative to existing methods.

Three-Component,One-Pot Synthesis of 2,4,5-Trisubstituted Imidazoles Catalyzed by TiCl4-SiO2 Under Conventional Heating Conditions or Microwave Irradiation

In this study, silica-supported titanium tetrachloride was prepared and used as a novel catalyst for rapid and efficient synthesis of 2,4,5-trisubstituted imidazoles by a three-component, one-pot condensation of 1,2-diketones and aryl aldehydes in excellent yield under solvent-free conditions using conventional heating or microwave irradiation.

Synthesis of New Iminocoumarins Bearing Parabanic Moieties

The synthesis of novel substituted 3-p-nitro-phenyliminocoumarins and corresponding N-ureaiminocoumarins is described. The condensation of these materials with oxalyl chloride leads to the corresponding N-parabanic iminocoumarins, which have not previously been described, in moderate or good yields and high selectivity. The structures were characterized by Fourier transform infrared, ¹H and ¹³C NMR, and elemental analysis.

Copper(I)-Catalyzed Cycloaddition of Methyl O-Propargylpodocarpate and Azides at Room Temperature

Copper iodide was employed as an efficient catalyst for the synthesis of 1,2,3-triazole derivatives of podocarpic acid at room temperature through “click” chemistry cycloaddition reactions of methyl O-propargylpodocarpate and propargyl O-propargylpodocarpate with azides.

Facile and Efficient Method for the Synthesis of 14-Substituted-14-H-dibenzo[a,j]xanthenes Catalyzed by Ruthenium Chloride Hydrate as a Homogeneous Catalyst

Synthesis of dibenzoxanthenes through condensation of β-naphthol with various aromatic and aliphatic aldehydes in ethanol as an ecofriendly solvent using Ru^III as catalyst is reported.

Novel Synthetic Routes of 3-Methoxypropanal from Glycerol

A new synthesis of 3-methoxypropanal from glycerol was presented. With this new approach, the conversion of glycerol to 3-methoxypropanal can be effected in moderate yield using catalysts of copper sulfate and polyethylene glycol (PEG).

Novel Asymmetric Synthesis of (S)-Esmolol Using Hydrolytic Kinetic Resolution

An efficient asymmetric synthesis of (S)-methyl 3-[4-[2-hydroxy-3-(isopropyl amino) propoxy] phenyl] propanoate is described. The key intermediate (S)-methyl 3-[4-(oxiran-2-ylmethoxy) phenyl] propanoate was obtained by hydrolytic kinetic resolution method using Jacobsen catalyst.

Recyclable Siloxy Serine Organocatalyst for the Direct Asymmetric Mannich Reactions in Ionic Liquids

A recyclable siloxy-L-serine organocatalyst has been developed to catalyze the asymmetric direct three-component Mannich reactions in ionic liquid hmim[PF₆], furnishing the β-amino carbonyl scaffold in high enantio- and diastereoselectivities. The direct Mannich reaction between a selection of aromatic aldehydes and ketones resulted in good yields and high enantioselectivities.

Stereoselective Synthesis of Dialkyl 2-(Arylsulfonylamino)-3-(dialkoxyphosphoryl) Succinates by Reaction of Trialkyl(aryl) Phosphites,Dialkyl Acetylenedicarboxylates,and Arylsulfonamides

A three-component reaction of trialkyl(aryl) phosphites, dialkyl acetylenedicarboxylates, and arylsulfonamides is described as a simple and efficient route for the synthesis of dialkyl 2-(arylsulfonylamino)-3-(dialkoxyphosphoryl)-succinates in good yields.

Use of Magnesium (Turnings) as a Powerful Catalyst for the O-Acylative Cleavage of Tetrahydrofuran

In a short reaction time, acyl chlorides and dry tetrahydrofuran react in the presence of a catalytic amount of magnesium turnings (Mg) at 25 °C to give 4-chlorobutyl esters in excellent yields.

FeCl3 · 6H2O-Catalyzed Acceleration of the Acylation of Sodium Azide with N-Acylbenzotriazoles

Catalyzed by ferric chloride hexahydrate (FeCl₃ · 6H₂O), the acylation of sodium azide with N-acylbenzotriazoles was greatly accelerated in a mixed solvent of acetone and water. Thus, good to excellent yields of a variety of acyl azides were obtained at room temperature in a short time. Furthermore, because of the complete conversion of N-acylbenzotriazoles and the easy removal of the by-product, purification by column chromatography was no longer required, which made the protocol suitable for large-scale preparation.

Highly Efficient One-Pot Synthesis of 2-Aminobenzoxazoles Using Triflic Acid as a Cyclodesulfurizing Reagent

An efficient one-pot synthetic strategy for 2-aminobenzoxazoles was developed from isothiocyanates and 2-aminophenol using triflic acid as a cyclodesulfurizing reagent.