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The practical synthesis includes an uncatalyzed reaction of aldomixes with carboxylic anhydrides.

A novel method has been developed for the synthesis of 1-ureidophosphonates through a three components condensation of aldehyde with amine and diethylphosphite in the presence of sulfanilic acid as catalyst followed by subsequent reaction of the product with isocyanate. This method is easy, rapid, and good yielding. The anticholinesterase (AChE) activities (inhibition potency through IC(50)) of newly synthesized 1-ureidophosphonates were also investigated. The activities of the synthesized compounds toward the enzyme AChE were determined and compared in terms of their molecular structures and it was found, through molecular docking simulations, that the most potent derivative (compound 3i) inhibited the enzyme through binding to the peripheral anionic site (PAS) and not to its acylation site (A site).

The preparation of the synthetically important phosphonates becomes possible under mild conditions and no tar formation is observed.

A simple, efficient and general method has been developed for the synthesis of 1-aminoalkyl phosphonates through a one-pot reaction of aldehydes with amines in the presence of acidic alumina under solvent-free conditions using microwave irradiation. It was also found that acidic alumina supported ammonium formate under solvent-free conditions is capable of the synthesis of 1-aminophosphonates from aldehydes and diethyl phosphite under mild reaction conditions.

Aminobisphosphinic acid (I) is activated by silylation with hexamethyldisilazane and subsequently treated with acid chlorides to give cyclic bisphosphinic acids (III).

Ring opening of epoxides (II) with (aminomethyl)phosphonates (I) occurs at the sterically less hindered position on the epoxide to afford the title compounds (III) in moderate to good yields.

The transformation of substrates (I) succeeds without any catalyst to give the synthetically important novel title compounds (III) in moderate to good yield.

Magnesia is found to be an effective catalyst for synthesis of diethyl 1-hydroxyarylmethylphosphonates from aromatic aldehydes and diethyl hydrogen phosphite.

Alumina in methanesulfonic acid is used to prepare o-hydroxyarylketones, by acylation of phenol and naphthol derivatives with carboxylic acids and Fries rearrangement of phenolic esters.

Phosphorylation of phenols with diethyl chlorophosphonate on the surface of magnesia is an easy, rapid, safe and high-yielding reaction.

Methanesulfonic acid/phosphorus oxychloride (MAPO) was found to be a new effecient reagent in the Fries rearrangement of phenolic esters. Fries rearrangement of phenolic esters in the presence of MAPO, gave acylaryl methane sulfonates as major products.

Alumina-supported CrO3, under solvent-free conditions, was found to be an efficient oxidizing reagent for the preparation of acyl phosphonates from 1-hydroxyphosphonates. This method is an easy, rapid, and high-yielding reaction for the preparation of acyl phosphonates from 1-hydroxyphosphonates.

Magnesium oxide/phosphorus oxychloride (MOPO) was found to be an efficient reagent for the preparation of 1,5-benzodiazepine derivatives of o -phenylenediamine and ketones. This method is an easy, rapid, and high yielding reaction for the synthesis of 1,5-benzodiazepine derivatives.

Microwave assisted Arbuzov rearrangement under solvent-free condition was found to be an efficient method for the preparation of dialkyl alkylphosphonates of alkyl halides. This method is an easy, rapid, and high-yielding reaction for the Arbuzov rearrangement.

The Reactions of 1-hydroxyphosphonates on the alumina-supported CrO3 are accelerated by microwave irradiation under solvent-free conditions to afford a high yielding synthesis of α-keto phosphonates.

A simple, efficient and general method has been developed for the synthesis of 1-aminoalkyl phosphonates through a one-pot reaction of aldehydes with amines in the presence of acidic alumina under solvent-free conditions using microwave irradiation. It was also found that acidic alumina supported ammonium formate under solvent-free conditions is capable of the synthesis of 1-aminophosphonates from aldehydes and diethyl phosphite under mild reaction conditions.

Alumina-supported ammonium formate was found to be an efficient reagent for the synthesis of 1-aminophosphonates from aldehydes and diethyl phosphite. This method is an easy, rapid and high-yieldin...

Phosphorylation of carboxylic acids with diethyl chlorophosphate on the surface of magnesia is an easy, rapid, safe and good yielding reaction.

Microwave-assisted hydrophosphonylation of aldehydes under solvent-free conditions was found to be an efficient method for the preparation of a-hydroxyphosphonates; the method was reliable, efficient and high yielding.

Alumina-supported CrO3, under solvent-free conditions, was found to be an efficient oxidizing reagent for the preparation of acyl phosphonates from 1-hydroxyphosphonates. This method is an easy, rapid, and high-yielding reaction for the preparation of acyl phosphonates from 1-hydroxyphosphonates.

Aminoaryl ketones are an important class of compounds that exhibit a variety of interesting and useful properties. 1 , 2 , 3 Some aminoaryl ketones are useful intermediates for the synthesis of ben...

A convenient preparative approach for the synthesis of aminomethylene bisphosphonates is developed which involves treatment of amines with triethyl orthoformate and diethyl phosphite under microwave irradiation.

The anticholinesterase activities of newly synthesized phosphorothioates and phosphorodithioates were investigated. The compounds were evaluated for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition potency through IC50 determination. The selectivities of the synthesized compounds toward both enzymes were determined and compared in terms of their molecular structures.

A simple, efficient, and general method has been developed for the one-pot synthesis of α-aminophosphonic esters, under solvent-free conditions, with the use of CaCl2 as a Lewis base catalyst. The ...

Synthesis of α-amino-α′-hydroxyphosphinates has been achieved through hydrophosphinylation of α-amino- H-phosphinates to aldehydes with highly retentive phosphorus chirality. Treatment of α-substituted α-amino- H-phosphinates with aldehydes in the presence of magnesium oxide without solvent gave α-amino-α′-hydroxyphosphinates. The reaction proceeded with 80-94 % retention of configuration at the phosphorus atom.

Diastereoselective addition of α-substituted α-amino-H-phosphinates to imines is described. Among Lewis acids, Yb(OTf)3 was found to be the best catalyst. α,α′-Diaminophosphinic derivatives were obtained with de's ranging from 10 to 95% in the presence of Yb(OTf)3 as an efficient Lewis acid catalyst. The reaction proceeded with retention of configuration at the phosphorus atom.

The reaction of aromatic and aliphatic aldehydes with hypophosphorus acid under microwave irradiation was examined. The reaction gave a mixture of a racemic pair of bis(alpha-hydroxyalkyl)phosphinic acids and acetal derivatives from the corresponding bis(alpha-hydroxyalkyl)phosphinic acids of meso-stereochemistry in good yield. The difference in solubility in organic solvents due to polarity allowed us to readily separate these compounds. This method constitutes an easy, rapid, and good-yielding preparation and separation of bis(alpha-hydroxyalkyl) phosphinic acid diastereoisomers from simple starting materials using microwave irradiation.

A simple, efficient, and new method has been developed for the synthesis of alpha-acetoxyphosphonates from aldehydes through a one-pot reaction of aldehydes with diethylphosphite in the presence of acetic anhydride under solvent-free conditions using magnesium oxide. This method is easy, rapid, and high yielding for the one-pot synthesis of alpha-acetoxyphosphonates from aldehydes.

A simple, efficient, and new method has been developed for the synthesis of thioamides from nitriles. The reaction of a variety of aromatic and aliphatic nitriles in the presence of phosphorus pentasulfide afforded the corresponding thioamides in high yields. This method is easy, rapid, and high-yielding for the synthesis of thioamides from nitriles.

Alumina supported ammonium fluoride was found as an efficient reagent for the synthesis of 1,2,4-oxadi-azoles of amidoximes under solvent free conditions using microwave irradiation. This method is a one-pot, easy, rapid, and high-yielding reaction for the synthesis of 1,2,4-oxadiazole derivatives from amidoximes and acyl chlorides. Reaction of amidoximes with acylchlorides in the presence of alumina without ammonium fluoride gave only the corresponding O-acylamidoximes as major product.

A simple, efficient, and general method has been developed for the synthesis of bis-(α-hydroxyalkyl)phosphinic acids from hypophosphorous acid using microwave irradiation. Bis-(α-hydroxyalkyl)phosphinic acids were obtained in high yield under mild conditions by reaction of hypophosphorous acid with aldehydes under microwave irradiation.

Silica-supported ammonium hydrogen carbonate was found to be an efficient reagent for the synthesis of 1-aminophosphonates under microwave irradiation in solvent-free conditions. This method is an easy, rapid, one-pot, and good-yielding reaction for the synthesis of 1-aminophosphonates.

Microwave-assisted synthesis of 1,2,4-oxadiazoles of amidoximes under solvent free conditions was found to be an efficient method for one-pot synthesis of 1,2,4-oxadiazole derivatives from amidoximes and acyl chlorides. This method is an easy, rapid, and high-yielding reaction for the synthesis of 1,2,4-oxadiazoles.

A simple, efficient, and general method has been developed for the synthesis of α-aminophosphinic acids from hypophosphorus salts under solvent-free conditions using microwave irradiation. α-Aminophosphinic acids were obtained in high yield under mild conditions by reaction of the amine salts of hypophosphorus acid with aldehydes in the presence of microwave irradiation.

The diastereoselective synthesis of β-substituted α-hydroxyphosphinates was achieved by hydrophosphinylation of α-oxy aldehydes and α-amino aldehydes with ethyl allylphosphinate catalyzed by lithium phenoxide.

A simple, efficient, and general method has been developed for the synthesis of 1-aminophosphonates from 1-hydroxyphosphonates under solvent–free conditions using microwave irradiation. 1-Aminophosphonates were obtained in high yield and mild conditions by reaction of diethyl 1-hydroxyalkylphosphonates with amines in the presence of acidic alumina.

Phosphonate esters are versatile intermediate in organic synthesis. These compounds have found a wide range of application in the areas of industrial, agricultural, and medicinal chemistry owing to their physical properties as well as their utility as synthesis intermediates. The synthesis of some phosphonate esters under solvent free condition was described. These methods are easy, rapid, and high-yielding reactions for the synthesis of phosphonate esters.

A simple, efficient, and general method has been developed for the synthesis of thiophosphates through a one-pot reaction of alkyl halides with the mixture of diethyl phosphite in the presence of ammonium acetate/sulfur and acidic alumina under solvent-free conditions using microwave irradiation.

Treatment of aromatic aldehydes with ammonia and hypophosphorus acid gave C 2-symmetric 1-aminoarylmethylphosphinic acids. The latter compounds, activated in the presence of hexamethyldisilazane (HMDS) or trimethylsilyl chloride (TMSCl), successfully reacted with methyl acrylate to afford symmetric pseudodipeptides. The applied synthetic approach is briefly outlined here.