Studies on Synthesis and Biological Activities of Novel Triazole Compounds Containing 1,3-Dioxolane

IntroductionTriazole compounds have attracted muchattention having been used as high efficient andwide spectrum fungicide and plant growthregulator[1— 4] .The triazole compounds containtintg1 ,3- dioxolane have the remarkable prevention ofthe control over plant diseases[5] .Propiconazol anddifenoconazole are two important representatives.But the necessary intermediate for synthesizingpropiconazol depends on imports,which leads tothe cost of production and application too high.According to th…     

Optimization of Grignard ring-opening of α-brominated dioxolanes for the preparation of β-hydroxy-protected vinyl ethers by a three-step one-pot procedure

Aliphatic, cyclic, and aromatic benzoate-protected γ-hydroxy enol ethers were prepared from α-brominated dioxolanes by a three-step reaction procedure and a one-pot protocol involving Grignard reagent formation, ring-opening, and final benzoate protection. Additionally, tert-butyldiphenylsilyl, acetate, and 4,4′-dimethoxytrityl were also successfully used as alternative protecting groups.     

Synthesis of Novel Galactopyranosyl‐Derived Spiro Barbiturates

Abstract

Malonic acid undergoes condensation readily with ureas to yield barbituric acids 2, which on bromination give 5,5‐dibromobarbituric acids 3. Reaction of α‐D‐galactose with these 5,5‐dibromo barbituric acids afforded 2,3‐α‐D‐galactopyrano‐1,4‐dioxo‐7,9‐diaza‐spiro[4,5]deca‐6,8,10‐triones 4. The structures of the products have been assigned on the basis of ¹H NMR, ¹³C NMR, FAB‐MS, optical activity, and elemental analysis. The title compounds are found to have antibacterial and antifungal activities.     

Synthesis and polymerization of a novel perfluorinated monomer

Perfluoro(5-methylene-2,2-dimethyl-1,3-dioxolane) (1) was synthesized by utilizing a direct fluorination reaction. Compound 1 was an entirely novel monomer with difluoromethylene at position 5 on the dioxolane ring as an unprecedented polymerization site. It successfully polymerized with tetrafluoroethylene to afford copolymers, which had T_g values in the range of 60-90 °C. The content of monomer 1 in the obtained polymers was less than 20 mol%, which seemed insufficient for giving various unique properties to polymers. However, each polymer was expected to be a superior material because of their advanced thermal stability. Comparison with copolymers of 2,2-bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole and tetrafluoroethylene is also discussed.     

Synthesis and catalytic applications of new chiral ferrocenyl P,O ligands

A new method to synthesize both enantiomers of 2-diphenylphosphino-ferrocenecarboxaldehyde with the phosphine group protected as a thiophosphine group was developed. These aldehydes react with 1,2 or 1,3 diols to give, in good yields, new chiral phosphine-acetals. For unsymmetrical (R)-1,3-butanediol, the new asymmetrical acetalic carbon is asymmetric and its configuration was completely controlled by the chirality of the diol. These new P,O ligands were tested in the palladium-catalyzed asymmetric allylic substitution of 1,3-diphenylprop-2-enylacetate. Good yields and enantioselectivities up to 77% were observed. The catalytic performances of two diastereoisomeric ligands with opposite configurations in planar chirality only proved to be significantly different, showing a strong influence of both planar and central chiralities.     

含聚1,3-二氧戊环链段聚合物网络Poly(AA-b-DXL)溶胀度的影响因素研究

继报道了含聚 1,3 二氧戊环 (PDXL)链段具有pH敏感性的可解体聚合物网络Poly(AA b DXL)的制备后 ,对网络的溶胀性能进行了更为详细和深入的研究 .由PDXL与PAA两种亲水性链段组成的网络不仅具有pH敏感性 ,而且可在水中及有机溶剂中溶胀 .研究表明溶剂的溶度参数及网络的结构与组成对网络的溶胀性能有显著的影响 ;在这种亲水性的网络中存在微相分离结构