两种结构钼磷酸的催化氧化行为

考察了Dawson与Keggin结构钼磷酸的催化氧化行为,并与结构特性进行了关联,结果发现,Dawson结构的杂多酸对氧化脱氢及插入氧反应均有更高的活性。     

Ln(Ⅲ)-Cu(Ⅱ)与直链醚-氨基酸新型Schiff碱异核配合物合成和催化

合成Ln(Ⅲ ) Cu(Ⅱ )与全新型直链醚 氨基酸Schiff碱的异核配合物并提出合成方法 .经元素分析、磁化率、光谱及 2D COSY NMR等表征 ,确定其组成为 [LnCu2(H2 TALY) (NO3 ) 5 ](NO3 ) 2 ·nH2 O (Ln =La ,Nd ,Sm ,Gd ,n =4;Ln =Yb ,Y ,n =3) ,式中H2 TALY为四甘醇醛缩双赖氨酸Schiff碱 .探讨了配位作用 ,特别有意义的是该类新配合物在不加助催化剂时 ,可单独催化聚合甲基丙烯酸甲酯 (MMA) ,转化率可高达1 0 0 % ,分子量约为 1 2万 ,它们可能成为一类具有特点的新催化剂体系 ,同时证明脂肪族Schiff碱配合物对MMA聚合反应也具有优良的催化活性     

二氯亚甲基环己烷的卤化反应和2-取代二氯亚甲基环己烷的构象

多卤代烃在有机反应机理和结构研究中有着重要意义,作为一个有用的合成中间体,其制备也受到人们重视。我们在此报道二氯亚甲基环已烷(1)与氯及溴的反应和其它有关反应的实验结果。 1 于氯作用,主要得到加成产物1—氯—1—     

新型18核铜-稀土簇合物|Cu_(12)RE_6(OH)_(24)(Pyb)_(12)(H_2O)_(18)(ClO_4)|~(17+)的合成与结构

新型标题18核钢-稀土簇合物从pH3.5的Cu~(2+)-RE~(3+)-pyb(RE=Sm,Tb,pyb=吡啶甜菜碱)水溶液反应体系中分离,经单晶结构测定.分析表明,簇合物阳离子具有一个包裹μ_(12)-ClO_4~-配体的八面体结构的[Cu_(12)RE_6(μ_3-OH)_(24)(μ_(12)-ClO_4)]~(17+)核,其外围有18个水分子和12个桥连pyb羧基配体.     

粤北产五味子科植物风沙藤的化学成分研究(II)

本文继续报道从粤北所采集的五味子科植物风沙藤(Schisandra viridis A. C.Sm)根和茎中分得的另外三个木脂素类新化合物, 即五味子酯(schisantherin)K,五脂酮(Schisanlignone)E和异安五脂素(isoanwulignan)。通过光谱分析和化学转变, 确定了它们的结构和构型。     

An Efficient Deselenenylation Reaction to the Synthesis of 3, 5-Disubstituted Isoxazoline and Isoxazole

The development of organoselenium chemistry1 has been expanding rapidly during the last decades. Among them, organic selenides are key intermediates, for that they can be efficiently introduced, manipulated, and removed through selenoxide syn-elimination2. Our research group3 has been interested in the application of selenium in organic synthesis for several years. Isoxazolinyl substituted phenyl selenide 13a, although a β-H exists in the molecule, did not undergo selenoxide syn-elimination e…     

Chemical Constituents of Ailanthus triphysa

Two new compounds,8(14),15-isopimaradiene-2α，３α，19-triol(1),and 6α，７β－dihydroxy-17(20)-cis-5α－pregna-16-one(2),together with four known copounds,a oxygenated rare phyllocladane,phyllocladan-16α，19-diol(3),kaempferol-3-0-β－Ｄ-galactopyranosied,kaempferol-3-0-α－Ｌ－rhamnopyranoside and scopoletin, were isolated from the leaves of Ailanthus tripysa.Structures of 1-3 were elucidated on the basis of spectroscopic data as compared with related compounds.     

Two New Isobutyltartrate Monoester from Coeloglossum viride （L.） Hartm.var.bracteatum（Willd.） Richter

Two new isobutyltartrate monoesters,coelovirin A (1) and B(2),were isolated from the rhizomes of Coeloglossum viride (L.) Hartm. var. bracteatum (Willd.) Richter (Orchidaceae). Their structures were elucidated as (2R,3S)-2-isobutyltartrate-1-(4-β-D-glucopyranosyloxybenzyl) ester 1 and (2R,3S)-2-isobutyltartrate-4-(4-β-D-glucopranosyloxybenzyl) ester 2 on the basis of physical constants and spectroscopic methods including 2D NMR techniques.     

2—（4—氨酰基—2—噻唑基）—1,4—脱水—L—木糖醇及其氟代衍 …

用计算机分析模拟方法研究了２－（４－氨酰基－２－噻唑基）－１，４－脱水－Ｌ－木糖醇及其氟代衍生物的糖基构象，计算结果显示，６个碳核苷类似物的糖基构象均为Ｓ型。核磁共振谱和晶体Ｘ射线衍射结果与计算结果相吻合。