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The Darzens condensation reaction of aromatic aldehydes with phenacyl chloride proceeded very efficiently in a water suspension medium in the presence of triethylbenzylammonium chloride and only trans-2, 3-epoxy-l, 3-diaryl-l-propanones were formed which can be isolated simply by filtration. The structures of these compounds were confirmed by elemental analysis, IR and 1H NMR spectra. Their configurations are in agreement with that of the same compounds reported in the literature. Compared to the classical Darzens condensation, this new method has the advantages of good yields, high stereoselectivity, low running cost inexpensive and environmentally benign procedure.

2-Phenyl-3-thioformylindolizine and 1,2-dimethyl-3-thioformylindolizine undergo a novel desulfur coupling reaction in the presence of tributylphosphine to give (E)-1,2-bis(3-indolizinyl)ethenes in high yields. The structures of products were confirmed by IR, 1H NMR, MS, elemental analysis and single crystal X-ray diffraction analysis. The mechanisms involved in various stages of the reaction were discussed.

The vinylation of 4′-iodobenzocrown ethers was achieved in good yields by using polymeric palladium catalysts P-Ph-Phen-Pd(reduced) and P-Ph-bpy-Pd(0).

The palladium catalyzed vinylation of alkyl halides, especially benzyl chlorides, with a variety of olefins has been studied. A possible free radical mechanism was proposed.

Diamino oligoethylene glycols and amino polyethylene glycols were prepared in good yields by using the reaction of sodium diformamide with oligoethylene glycol or polyethylene glycol dichlorides or ditosylates followed by hydrolysis using ethanolic hydrochloride.

2-Arylethylamines were synthesized in moderate yields via Heck reaction of acrylamide with iodobenzenes in the presence of polymeric catalyst P-ph—phen. Pd (0) followed by hydrogenation and subsequent Hofmann reaction.

Three amino-functionalized silica-supported palladium catalysts have been synthesized. These catalysts displayed high activity for the Heck reaction of iodobenzene with olefins. By using XXX—aminopyridine-palladium, a turnover number exceeding 16700 was observed for the reaction of iodobenzene with styrene or acrylamide. This catalyst can be recovered and reused by using tributylamine as base. It can also tolerate the presence of a variety of functional groups.

The effects of different bases on Heck arylation catalyzed by the polymeric catalyst have been studied. The yield of product and the lifetime of the catalyst are influenced by the nature of the base used. The leaching of palladium from the polymeric catalyst is caused mainly by the competitive complexation of the ligands existing in the reaction media towards the metal. When tributylamine is replaced by DMF-H 2 O-NaOAc, the catalyst can be easily recovered and reused, the yields are higher and the products are found to be more pure. For the reaction of acrylamide with iodobenzene, even after ten consecutive runs the recovered catalyst still has high catalytic activity. In the DMF-H 2 O-NaOAc system, the catalyst can also tolerate the presence of a variety of functional groups; acrylamide could be introduced to react with substituted iodobenzenes in good yields.

Several N,N-diformylaminomethyl ketones were prepared by treating the respective bromomethyl ketone with sodium diformylamide in acetonitrile at room temperature. This reaction produced N-formylaminomethyl ketones (I) when ethanol was used as the solvent. One of the formyl groups of N,N-diformylaminomethyl ketones was selectively removed by using a catalytic amount of sodium or potassium hydroxide in alcohol to the corresponding N-formylaminomethyl ketones I. The formyl groups of both N,N-diformyl- und N-formylaminomethyl ketones could be easily removed by either 5 % hydrochloric acid in ethanol or 6 N hydrochloric acid to give the corresponding aminomethyl ketone hydrochlorides .These reactions are general and give high yield of the products

(E)-8-Arylcamphenes 3 were obtained in moderate to good yields by the reaction of camphene (1) with a variety of arenediazonium tetrafluoroborates 2 in the presence of palladium acetate under mild conditions. The E-configuration of the products was confirmed by 1 H-NMR analyses of the reaction mixtures of photoisomerization of 3, the Nuclear Overhauser Effect (NOE) of 3a and by comparison with an authentic sample of 4j