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A recyclable heterogeneous hydroxyapatite-supported palladium(0) catalyst was prepared by a simple procedure and successfully applied for the selective reduction of carbon–carbon double bond in α,β-unsaturated ketones using HCOONH4 as hydrogen transfer agent. The workup procedure is simple, and the catalyst could be recovered by simple filtration and recycled for five consecutive runs without significant loss of activity.

Solvent-free reactions of 2- and 3-halopyridines with PPh 3 , PBu 3 , and PCy 3 were studied under conventional heating, as well as under microwave irradiation. No difference was observed in the reaction course between classical and microwave reactions. 2-Bromopyridine gave quantitative yields of 2-pyridyltriphenylphosphonium bromide within few minutes at 190°C. Equimolar amounts of some inorganic salts (LiPF 6 , LiOTf, LiBr, NaPF 6 , KPF 6 ) were necessary for the reactions of the other 2-halopyridines. 3-Halopyridines did not react with PPh 3 even in the presence of LiPF 6 . Their reactions with PCy 3 in the presence of LiPF 6 resulted in the quantitative formation of dicyclohexylphosphine oxide.

A simple, rapid, and highly efficient method has been developed for the Michael addition of active methylene compounds to chalcones using potassium carbonate and water under microwave irradiation. The method is totally exempt of organic solvents, and pure products were obtained in good to excellent yields. This method can be used for the parallel synthesis and further scale‐up to 50 mmol of substrate.

Michael addition reaction between EMME and various O, S, N nucleophiles were investigated in the presence of catalysts such as KF, KOH, or K(OCCH3)3 under solvent‐free conditions either neat or on alumina as solid support. Compared to low reactivity of alcohols (40 to 80% yields according to aliphatic chain), aniline or thiophenol gave good to excellent yields (90–99%).

2,4,8-Trisubstituted-1,5-benzothiazepines (synthesized ‘in situ’) have been selectively oxidised to the corresponding sulfones via a one-pot procedure in 9 min. with 91% yield under microwave irradiation coupled with clay-supported ferric nitrate.

An improved facile one-pot synthesis of 3′-(fluorophenyl)-spiro[3H-indole-3,2′-tetrahydro-1,3-thiazine]-2,4′(1H)-dione is reported using an environmentally friendly green chemistry procedure under microwave irradiation. The crystal structure of the reported compound has been determined by a X-ray diffraction. The molecule is largely planar and has cell parameters of a = 11.181(9) A, b = 11.06(1) A, c = 12.715(12) A, α = 90°, β = 98.31(7)°, γ = 90°.

(2003). EFFECT OF CATIONS, SUBSTRATES AND TEMPERATURE ON THE MICROWAVE-ASSISTED SAPONIFICATION OF BENZOIC AND MESITOIC ESTERS. Organic Preparations and Procedures International: Vol. 35, No. 4, pp. 361-368.

A simple and efficient method has been developed for the rapid synthesis of substituted 4H-1, 4-benzothiazines (3) from 2-aminobenzenethiols (1) and β-ketoester/β-diketones (2) in dry media under microwave irradiation using basic alumina as solid support.

1,1-diethylthiourea and 4-methylbenzoic acid were condensed to 1-(4′-methylbenzoyl)-3,3-diethylthiourea in open vessels under microwave irradiation using an unmodified domestic microwave oven. The synthesis was carried out in the presence of alumina impregnated with potassium fluoride and catalytic amounts of N,N-dimethylformamide. The yields are noticeably improved in comparison with classical methods.

Fischer condensation was performed in 50-60% yield in lower temperatures and shorter times if conducted in solvent-free acid medium under microwave irradiation.

(1997). SYNTHESIS OF AMINOTOLUENESULFONAMIDE DERIVATIVES USING CONVENTIONAL HEATING OR MICROWAVE-ASSISTED METHODS. Organic Preparations and Procedures International: Vol. 29, No. 6, pp. 671-677.

The synthesis of several polyfunctional pyridazine derivatives has been carried out very efficiently under microwave irradiation and solvent-free conditions allowing short reaction times and high yields. Non thermal effects induced by microwave were observed.

A three step microwave assisted solvent-free synthesis of decyl D-glucopyranoside with 1-decanol was established for D-glucose and extended to D-galactose, D-mannose and N-troc-D-glucosamine with 70% average overall yield for the three steps (peracetylation, glycosylation and saponification). Rate enhancements and reduction of the reaction time were observed for the two last steps carried out under microwave irradiation when compared to conventional heating in the same conditions.

Permethylation of diospyrol was considerably improved in solvent-free PTC conditions. An excellent yield (92%) was obtained in 30 minutes using solid KOH + 5% Aliquat 336 and dimethyl sulfate, to be compared with 40% in acetone in 10 hours.

N-Acetyl-N-benzyloxy-β-alanine was obtained by Michael addition of N-acetyl-N-benzyloxyamine on terbutylacrylate under solvent-free PTC conditions followed by elimination of the terbutyl group. Polyamines were acylated with N-acetyl-N-benzyloxy-β-alanine. The prepared compounds exhibited a moderate activity against HIV protease.

Diethyl acetamidomalonate was efficiently alkylated with electrophiles of low reactivity under modified phase transfer-catalysis conditions in the absence of organic solvent using potassium tert-butoxide as a base.

A fatty epoxide (tetradecyl-oxirane) is reacted with diethyl acetamidomalonate in basic medium, with or without solvent under solid-liquid phase transfer catalysis with LiCl, or under microwave irradiation on supported reagents (KF/Al2O3/LiCl). The main product is a lactone which is formed after epoxide ring opening and subsequent cyclisation. We put here into evidence, for the first time, the conjugated advantages of “dry media” reactions, lithium salt effects and microwave irradiation.

α-n-amylcinnamaldehyde (jasminaldehyde) was obtained with 82 % yield by solid-liquid phase transfer catalysis without solvent within 3 days at room temperature. By use of domestic microwave irradiation, the same yield was obtained within 1 minute at a power of 600 W.

Hindered esters can be easily saponified in a few minutes using microwave activation under solid-liquid PTC conditions without solvent. A monomode microwave reactor (Maxidigest MX 350 Prolabo) is the most efficient. A non thermal effect of microwaves is evidenced by reference to classical heating.

Isomerization of eugenol can be efficiently performed using 2.2 mol. equiv. of KOtBu and catalytic amount of transfer agent in the absence of solvent. The best conditions (94% within 18 minutes) were obtained in a focused open-vessel Maxidigest MX 350 microwave reactor.

Isomerization of safrole and ethyleugenol are performed quasi-quantitatively within 5 minutes at 80°C using KOH or KOtBu and catalytic amount of transfer agent in the absence of solvent. Transfer agent can be avoided in the case of KOtBu with eventually increase in reaction time. Isolated yields of 99% are obtained from 10 g of materials.

The use of Solid-Liquid Phase Transfer Catalysis without Solvent permits, by a careful selection of the reaction conditions, the selective preparation of the four products expected in the butylation of acetophenone.

The Montmorillonite KSF catalyses the synthesis of anhydrides from carboxylic acids in the presence of isopropenyl acetate under microwave irradiations.

The alkylation of benzamide, N-methylbenzamide and N,N′-dimethylterephthalamide is performed by phase transfer catalysis without solvent. The method provides good selectivity and high yields, except in the case of N,N′-dimethylterephthalamide, together with economic and safe reaction conditions.

We report a simple and quick synthesis of tetrapyrrolic macrocycle in dry media conditions, under microwave irradiation. Heating in microwave oven pyrrole and benzaldehyde adsorbed on a solid acidic support affords tetraphenylporphyrin within ten minutes with very simplified treatment and purification.

Solid-liquid phase transfer catalysis in the absence of any added solvent efficiently promotes Michael addition of glycine Schiff bases to phenylvinylsulfoxide. The vinyl group was formed by thermolysis of the phenylsulfinyl function.

The alkylation of phenol, hydroquinone and p-aminophenol is performed by phase transfer catalysis without solvent. High yields of α,ω-diphenoxyalkanes, hydroquinone diethers and high selective mono O-alkylation of p-aminophenol are obtained in very mild conditions.

Solid-liquid PTC without added solvent efficiently promotes SNAr reactions of a variety of anionic nucleophiles generated in situ. This methodology is applied with success to some examples concerning non-activated aromatic systems. TDA-1 is the most effective catalyst.

Owing to cumulative effects of microwave irradiation and solid-liquid PTC without solvent methodology, conditions for alkylations of potassium acetate by n-octyl or n-cetyl halides are nearly quantitative within 2 minutes on appreciable quantities.