in this paper, to account for the effect of water stresses in the various growth stages under deficitirrigation, the multiplicative, seasonal and minimal approaches are integrated in the budgetmodel. to evaluate the model, the simulated yields for winter wheat (was grown in sharif abaddistrict) under various levels of water stress were compared with observed yields. the resultshowed, simulated ...

the wittig reaction rate can be dramatically enhanced by irradiation of the reaction mixture containing an aldehyde or ketone; methoxymethyl(triphenyl)phosphonium chloride, potassium t-butoxide, and t buoh with a commercial microwave oven. carbonyl compound are converted to witting products within three min. in good yields.

the synthesis and characterization a new derivatives of 2'-iodo-meta terphenyl from the reaction ofexcess aryl-grignard and 2, 6- dichloroiodobenzene with quenching of m-terphenyl-2'-magnesiumbromide by iodine is reported. via the reactions three carbon-carbon bonds are constructed and mterphenylsare obtained in good yields.

substituted naphthofurans and naphthopyrans were constructed at high temperature from allyl or propargyl naphthyl ethers via claisen rearrangement in moderate to good yields. also, substituted (trimethylsilyl)-naphthofurans were synthesized from the corresponding naphtofurans.

microwave-assisted three component cyclocondensation reactions of aldehydes, amides and dienophiles in the presence of acetic anhydride and para-toluenesulfonic acid as a catalyst to afford the highly substituted cyclohexene derivatives, in relatively good yields after several minutes are reported.

A simple and efficient method for the synthesis of quinolines and polycyclic quinolines using Li+ modified nanoporous Na+-montmorillonite is described. This new nanocatalyst proceeds via Friedlander annulation under solvent-free conditions. It describes our observations about a trend of catalytic activity of Lithium cation in nanoporous Na+-montmorillonite. In this study, several types of 1,3-d...

5-acetyl-6-methyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones were synthesized in good to excellent by one-pot three-component Biginelli condensation in the presence of ammonium salt [Et3NH][HSO4] as an inexpensive and green catalyst under solvent-free conditions. High yields, short reaction time, easy work-up, a green environment which requires no toxic o...

suzuki cross-coupling reaction of different aryl halides with arylboronic acids was successfully carried out in methanol using ortho-palladated complex of 2-methoxyphenethylamine. all substrates afforded the corresponding products in good to high yields in the presence of low amounts of this complex as efficient and active catalyst. application of microwave irradiation improved the yields of th...

4-Hydroxyquinazoline undergoes neutral conditions with alkyl propiolates in the presence of triphenylphosphine (0.26g), and by α substituation the corresponding  2-(4-oxoquinazolin-3(4H)-yl acrylate was obtained in good yields.

Eggshell was found to be a versatile heterogeneous catalyst for the synthesis of pyrano[3,2-c]quinoline derivatives in good yields. This protocol has the advantages of environmental friendliness, short reaction time, low cost and convenient operation.