微波辐射下苯并(口恶)唑基吡啶的合成

含有苯并唑基的杂环化合物由于其特殊的生理活性而广泛用作医药、农药[1];因为具有较高的荧光量子产率,还可作为荧光增白剂、闪烁剂[2]等。现有合成方法反应时间长[3,4],而且需高温下进行。微波辐射下的有机合成具有反应时间短、产率高的特点[5]。本文在微波辐射条件下,利用邻氨基酚和吡啶羧酸的缩合反应,合成了2种苯并唑基取代吡啶。其优化反应条件为:多聚磷酸为催化剂,微波输出功率为500W,辐射时间4分钟。相比于常规反应,该条件下的反应速率是常规加热法反应速率的60倍且产率有所提高。合成路线如下:ppA=Polyphosphoricacid1　…     

碘化4-(2-苯并噁唑)-N-甲基吡啶盐的合成和晶体结构

合成了标题化合物碘化 4- ( 2 -苯并唑 ) - N-甲基吡啶盐 ,并对其晶体结构进行了测定 .晶体数据 :C1 3H1 1 IN2 O,Mr=338.15 ,单斜晶系 ,空间群为 C2 / c,a=1.0 0 16 ( 3) nm,b=1.782 0 ( 6 ) nm,c=0 .7399( 1) nm,β=10 9.16 ( 2 )°,V=1.2 434 ( 6 ) nm3,Z=4,Dx=1.81g/ cm3,μ=2 5 .3cm- 1 ,F( 0 0 0 ) =6 5 6 .结构偏离因子 R=0 .0 2 7,Rw=0 .0 35 .结构测定表明 ,有机阳离子中两个杂环平面之间的夹角为 148.9°,是一个大的共轭体系 ,有可能实现自身内部的电子转移     

双(苯并噁唑)芪的光物理行为及其异构化反应的研究

研究了双(苯并噁唑)芪的光物理行为和光顺反异构化反应,对这类化合物的发光光谱不依赖于溶剂极性的原因进行了初步讨论。异构化反应中,发现乙二醇引入时会加速该化合物反-顺异构化和抑制顺-反过程的回复,其原因可能是与生成了顺式异构体两个苯基苯并噁唑间的氢键有关。     

A facile synthesis of polyfoluoroalkyl-lactonization

2(-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.     

1，4-双{2-[4-[2-苯并恶唑)苯基]乙烯基}苯及衍生物的合成

通过Wittig-Horner反应，以对苯二甲醛和2—(4-氯甲基苯基)苯并恶唑为主要 原料，合成了八个新型1，4-双{2-[4-(2—苯并恶唑)苯基]乙烯基}苯及衍生物．通 过IR，^1H NMR,UV-vis和元素分析等方法确认了它们的化学结构，分析数据表明各 标题化合物分子结构中的C=C双键均为反式结构特．     

Polarized Ketene Dithioacetals‐Versatile Synthons for Different Heterocycles

The reactivity of polarized ketene dithioacetals to develop a variety of heterocycles under different conditions was studied.     

N-Substituted benzoxazolyl ureas and thioureas in Biginelli reaction promoted by trifluoromethane sulfonic acid:An efficient and convenient synthesis of substituted benzoxazolyl 3,4-dihydropyrimidine(1H)-(thio)-ones

An efficient synthesis of 3,4-dihydropyrimidine 2(1H)-ones and thiones(3,4-DHPMs) core was prepared by one-pot threecomponent Biginelli condensation and which was catalyzed by trifluoromethane sulfonic acid.The classical Bignelli reaction has been extended by the use of N-substituted benzoxazolyl semicarbazides and thiosemicarbazides and this method has the advantage of excellent yields and short reaction times.     

Thermal decomposition and isomerization of 2,2'-di(benzoxazolyl) disulfide

Heating 2,2′-di(benzoxazolyl) disulfide at 140–150 °C results in its decomposition with the elimination of elemental sulfur to yield 2,2′-di(benzoxazolyl) sulfide and 3-(2-benzoxazolyl)benzoxazoline-2-thione. Plausible reaction mechanisms are discussed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1829–1831, October, 1993.     

A Facile Synthesis of Benzoxazolyl Cyclopropanes

2′-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.