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In this study, oxalic acid has been successfully loaded on Fe3O4/PEG-400 under ultrasonic irradiation and Fe3O4/PEG/oxalic acid as a new nanomagnetic catalyst has been synthesized. The chemical structure of the catalyst has been investigated by FT-IR spectrum, XRD, EDX and SEM methods. The catalyst has been used for the synthesis of 3-acyl-5-hydroxy-3-pyrrolin-2-one derivatives from the corresponding aldehydes, anilines and dimethyl acetylenedicarboxylate (DMAD) by one-pot and three-component the MCR reaction in the excellent yields (90-95 %) of products within 24 hours at room temperature. The fourteen samples are available. The recovered catalyst could be satisfactorily used for the second and third run without regeneration. This method has green and eco-friendly profile. Also, this research introduces an improvement mechanism for the types of this reaction. The chemical structures of new compounds have been characterized by FT-IR, 1H-NMR, 13C-NMR, and Mass spectra.

AmberChrom/brine as a Green Catalytic System for Synthesis of Pyrrolin-2-ones

Oximes have many applications in organic synthesis1. These compounds have antimicrobial, antioxidant, antitumor, anti-depressive, antiviral agents, and anticonvulsant properties2-7. Some oximation methods have been reported8. However our ongoing attentions to the development of new modified methods in organic synthesis8-15, we have investigated the oximation of a variety of carbonyl compounds with NH2OH·HCl in the presence of BaCl2. RESULTS ANd dISCUSSIONS

In this context, the one-pot three-component synthesis of 3-methyl-4-arylmethylene-isoxazol5(4H)-ones has been performed in the presence of citric acid as catalyst in water. The products have been obtained in high yields (70-90%) and convenient reaction times (5-24 hours). keywords: Citric Acid, isoxazol-5(4H)-one, one-pot reaction, water, green chemistry.

4-arylmethylidene-3-methylisoxazol-5(4H)-ones and 4-arylmethyl-idene-3-phenylisoxazol-5(4H)-ones have been synthesized in the one-pot three-component synthesis in the presence of Dowex1-x8OH as catalyst in water. The products have been obtained in high yields (90-95%) and proper reaction times (1-5 hours). This method has eco-friendly profile and operational simplicity.

In this study, molecularly imprinted polymer nanoparticles (MIP-NPs) for the selective pre-concentration of protriptyline have been described. The nano-sized protriptyline-MIP particles were synthesized using suspension polymerization in silicon oil with methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2-azobisisobutyronitrile as an initiator and protriptyline as a template molecule. The MIP-NPs were characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and thermo gravimetric analysis (TGA) methods. The effects of various parameters on the sensitivity of the method were investigated. Under the optimal conditions, the relative standard deviations (RSD) of peak area for 30 μg mL−1 of protriptyline in water and plasma were 3.4% and 4.1%, respectively. The method was applied to the determination of protriptyline in human plasma samples.

NaBH 4 (1.25 equivalents) & NaNO 3 (3 equivalents) reduce a variety of aldehydes in the presence of ketones to their corresponding alcohols. Also, regioselectivity and exclusive 1,2reduction enals to their corresponding allylic alcohols in high to excellent yields was achieved successfully with this reducing system. The reduction reactions were carried out in water as green solvent in high to excellent yields of the products. A nitrate-borane complex [H3B-NO3]Na is possibly the active reductant in the reaction mixture.

NaBH 4 (1-2 equivalents) in the presence of (NH 4 ) 2 SO 4 (1-2 equivalents) reduces varieties of organic carbonyl compounds such as aldehydes, ketones and a,â-unsaturated carbonyl compounds to their corresponding alcohols. Reduction reactions were carried out in THF-H 2 O in high to excellent yields of products.

The acylalation of structurally different aldehydes has been performed by Zn(BH4)2/Ac2O/DOWEX(R)50WX4 as new system within 1-5 min at room temperature with excellent yields of the products (92-97%).

Zn(BH4)2 (0.5-1.5 mmol) in the presence of charcoal (1 mmol) reduces a variety of organic carbonyl compounds such as al- dehydes, ketones, acyloins, α-diketones and α,β-unsaturated carbonyl compounds to their corresponding alcohols. Reduction reactions were carried out in THF at room temperature in high to excellent yields. The chemoselective reduction of aldehydes over ketones was successfully accomplished with this reducing system. In addition, regioselectivity and exclusive 1,2-reduction of conjugated carbonyl compounds to their corresponding allylic alcohols was also performed in in high to excellent yields with this reducing system. Resumen. Los compuestos carbonilicos como aldehidos, cetonas, aci- loinas, α-dicetonas y compuestos carbonilicos α,β-insaturados se redu- cen con Zn(BH4)2 (0.5-1.5 mmol) conteniendo carbon (1 mmol) a los alcoholes correspondientes. Este sistema reductor permite la reduccion quimioselectiva de aldehidos en presencia de cetonas y la reduccion regioselectiva de compuestos carbonilicos insaturados a los alcohols alilicos correspondientes con rendimientos de buenos a excelentes. Palabras clave: Zn(BH4)2, reduccion, compuestos carbonilicos, car- bon, quimioselectividad, regioselectividad.

A one-pot and three-component synthesis of 3-methyl-4-arylmethyleneisoxazol-5(4H)-ones was developed in the presence of DOWEX(R)50WX4 as the catalyst. The products were obtained in high yields (93-96%) and short reaction times (30-60 min). The present method provides an easy and efficient approach for the synthesis of this class of compounds, because of its clean reaction profile and operational simplicity.

The oximation of a variety of organic carbonyl compounds was efficiently carried out with NH 2 OH·HCl under microwave irradiation. The reactions were performed in water or water-ethanol as green solvents to give Z-aldoxime isomers from the corresponding aldehydes and E-ketoxime isomers from the corresponding ketones in a perfect selectively with excellent yields.

Reductive-acylalation of aldehydes has been carried out by NaBH4/Ac2O/DOWEX(R)50WX4 system. A variety of aldehydes (1 mmol) have been reacted with Ac2O (0.5 mL) and NaBH4 (1 mmol) in the presence of DOWEX(R)50WX4 (0.5 g) for the preparation of their corresponding acylals within 1 min at room temperature with excellent yields of the products (90-95%). Ketones do not react with this system.

In this context, NaBH4 in the presence of activated charcoal has been used for thereductive aminationofa varietyof aldehydes withanilines. The reductive amination reactions have been performed within 60-100 min in THFunder reflux conditionsin high to excellent yields of products (85-90%).

Thereductive aminationofa varietyof aldehydes withanilines has been carried out by NaBH4/ NaH 2 PO 4 .H 2 Oas new reducing systemswithin 55-100 min in THFunder reflux conditionsin high to excellent yields of products (85-92%).

The reduction of a variety of carbonyl compounds was efficiently carried out with [Zn(BH 4 ) 2 (2-MeOpy)] and [Zn(BH 4 ) 2 (2-Mepy)] as new reducing agents. The reduction reactions were performed to give the corresponding alcohols derivatives in perfect yields.

Structurally different secondary amineshave been synthesized byreductive aminationofavarietyof aldehydes and anilines with NaBH 4 /Ga(OH) 3 as new reducing systems in CH3CN at room temperature in high to excellent yields of products (88-95%).

α,β-unsaturated aldehydes and ketones are regioselectively reduced to the corresponding allylic alcohols with NaBH4/Ba(OAc)2 system in CH3CN. This system is also efficient for the chemoselective reduction of enals in the presence of enones at room temperature.

The reduction of a variety of carbonyl compounds was efficiently carried out with NaBH4/DOWEX(R)50WX4 system. The reactions were performed to give the corresponding alcohols derivatives in perfect yields in THF at room temperature. Reduction of acyloins and a-diketones by this reducing system produced efficiently the corresponding vicinal diols. Also, the reduction of aldehydes over ketones has been accomplished successfully by this system. Regioselectivity of this system was also investigated with exclusive 1,2-reduction of conjugated carbonyl compounds to their corresponding allylic alcohols in high to excellent yields.

The oximation of a variety of carbonyl compounds was efficiently carried out with DOWEX(R)50WX4/NH2OH·HCl system. The reactions were performed in ethanol to give Z-aldoximation isomers of aldehydes and E-oximaton of acetophenone derivatives in a perfect selectively. The oximation of compounds with two carbonyl groups was carried out selectively on one carbonyl moiety. Also, the oximation of aldehydes over ketones has been accomplished successfully by this system.

In the course of our study to dis-cover the new applications of this reagent, we found that thereduction of benzaldehyde with the reagent in ethyl acetateprovided benzyl alcohol and benzyl acetate. Encouraged bythe result, we undertook the study for one-pot reductiveacetylation of a variety of carbonyl compounds, such asaldehydes, ketones and α,β-unsaturated enals/enones, toacetates using the reagent (Scheme 1).

Reductive-acylalation of aldehydes has been carried out by NaBH4/Ac2O/DOWEX(R)50WX4 system. A variety of aldehydes (1 mmol) have been reacted with Ac2O (0.5 mL) and NaBH4 (1 mmol) in the presence of DOWEX(R)50WX4 (0.5 g) for the preparation of their corresponding acylals within 1 min at room temperature with excellent yields of the products (90-95%). Ketones do not react with this system.

Reduction of varieties of carbonyl compounds such as aldehydes, ketones, α,β-unsaturated aldehydes and ketones, α-diketones and acyloins was carried out very fast and efficiently by sodium borohydride in water under microwave irradiation. The corresponding product alcohols were obtained in high to excellent yields.

A variety of cyanohydrins were prepared from Aldehydes with sodium cyanide and DOWEX(R)50WX4 in a convenient procedure.

α-diketones and acyloins are reduced to the corresponding vicinal diols with Zn(BH4)2/ ZrCl 4 system in THF at room temperature.

Reductive amination a variety of aldehydes and anilines to their corresponding secondary amines were carried out with NaBH4/B(OH)3 and NaBH4/Al(OH)3 as new reducing systems in CH3CN at room temperature in high to excellent yields of products (90-96%).

Citral as α, β-unsaturated carbonyl compound has been reacted with structurally different anilines with sodium borohydride in the presence of boric acid for the synthesis of their corresponding N-citralbenzenamineswith good yields (75-85%)within 5 min in CH3CNat room temperature.

In the course of our study to dis-cover the new applications of this reagent, we found that thereduction of benzaldehyde with the reagent in ethyl acetateprovided benzyl alcohol and benzyl acetate. Encouraged bythe result, we undertook the study for one-pot reductiveacetylation of a variety of carbonyl compounds, such asaldehydes, ketones and α,β-unsaturated enals/enones, toacetates using the reagent (Scheme 1).

The NaBH4/C (charcoal) system reduces a variety of carbonyl compounds such as aldehydes, ketones, acyloins and α-diketones to their corresponding alcohols in high to excellent yields. Reduction reactions were carried out in wet THF at r. t. In addition, regioselective 1,2-reduction of α,β - unsaturated aldehydes and ketones was achieved perfectly with this reducing system. By decreasing the amount of aprotic solvent, all reductions took place fast and efficiently under solid-gel condition

NaBH4 in the presence of charcoal (0.4–0.8 g) reduces varieties of nitroarenes to their corresponding amines. Reduction reactions were carried out in a mixture of H2O‐THF (1:0.5 mL) at 50–60°C with high to excellent yields of products.

Zn(BH 4 ) 2 under ultrasonic irradiation is an efficient reducing system in CH 3 CN. This system reduces a variety of carbonyl compounds to their corresponding alcohols at room temperature in high to excellent yields of the products. Also, a,b-unsaturated aldehydes and ketones was regioselectively reduced to the corresponding allylic alcohols.