A facile access to ureido sugars. Synthesis of urea-bridged β-cyclodextrins

The preparation of a urea-bridged β-cyclodextrin dimer and of a 6-monodeoxy-6-mono[3-(β-d-glucopyranos-2-yl)ureido]-β-cyclodextrin has been developed, using triphosgene as the isocyanation agent in an aqueous two-phase system. Per-O-acetylated β-d-gluco and mannopyranosylamines and 2-amino-2-deoxy-α- and β-d-glucose were also transformed into the corresponding isocyanates and converted in situ into ureas by coupling with aromatic and aliphatic amines.     

CONDENSATION REACTION OF 1-OXO-4-CHLOROCARBONYL-1-PHOSPHA-2,6,7-TRIOXABICYCLO[2.2.2]OCTANE WITH N-t-BUTYL-N-BENZOYLHYDRAZINE

Abstract

1-Oxo-4-chlorocarbony1-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane (5) was obtained from phosphorus oxychloride. Benzyl chloroformate was synthesized by the reaction of benzyl alcohol and triphosgene in good yield for the first time. N-r-Butyl-N-benzoylhydrazine(II) was prepared in a new and convenivent procedure with good yield. The reaction of 5 and II proceeded smoothly in the presence of sodium carbonate and afforded the desired compound 13 in good yield, while in the presence of triethylamine, the elimination of butyl was observed and afforded the compound 12.     

Synthesis of N-t-Butyl-N'-Aminocarbonyl-N-(Substituted) Benzoylhydrazine Containing a -Aminoalkylphosphonate Groups

A variety of novel N-t-butyl-N'-aminocarbonyl-N-(substituted)benzoylhydrazines containing a -aminoalkylphosphonate groups were synthesized by the addition of N-t-butyl-N-(substituted)benzoylhydrazines to a -isocyanatoalkylphosphonates, which were synthesized by the reaction of a -aminoalkylphosphonates with triphosgene in good yields. The structures of products including by-products were confirmed by 1H NMR, 31P NMR, IR, mass spectroscopy, and elemental analysis.     

DIAR黄成色剂的合成

DIAR黄成色剂的合成;DIAR成色剂;异丙氨基苯硫酚;固体光气     

A Practical Synthesis of 1—Oxo—1,2,3,4—tetrahydroisoquinoline—3—carboxylic Acid Esters

A practical synthetic method for methyl 1-oxo-1,2,3,4-tetrahy-droisoquinoline3-3carboxylate was developed by menas of triphosgene,Several analogues were prepared by this new method.     

硝基苯异氰酸酯的制备及模拟计算

通过构型优化、热力学分析、电荷分布分析等计算,从理论上确定了硝基取代苯胺进行异氰化反应的容易程度为间硝基苯胺对硝基苯胺邻硝基苯胺.在此基础上对以固体光气与邻、间、对硝基苯胺为原料分别合成邻、间、对硝基苯基异氰酸酯的工艺进行了研究.结果表明,以乙酸乙酯作为反应溶剂,合成邻、间硝基苯基单异氰酸酯的最佳反应时间为6h,合成对硝基苯基单异氰酸酯的最佳反应时间5h,邻硝基苯胺、对硝基苯胺与固体光气的最佳物质的量比均为2∶1,间硝基苯胺与固体光气的最佳物质的量比为2.2∶1.在上述反应条件下,邻、间、对硝基苯基单异氰酸酯的收率分别达75.5%,76.9%和77.1%,纯度分别达99.6%,99.16%和85.7%,实验结果与理论推断基本相符.     

1-[5-(1,3-二氧-4,5,6,7-四氢-1H-异吲哚-2-基)苯基]-3-取代脲衍生物的合成与除草活性研究

为了寻找高效低毒的原卟啉原氧化酶抑制剂(protox)类除草剂, 设计并合成了一系列1-[5-(1,3-二氧-4,5,6,7-四氢-1H-异吲哚-2-基)苯基]-3-取代脲类衍生物4a～4d和5a～5g. 化合物4a～4d经异氰酸酯法合成, 收率、纯度高; 化合物5a～5g利用固体光气一锅法合成, 反应时间短.所得化合物结构经¹H NMR, IR, 质谱和元素分析表征. 初步生物活性测试表明: 化合物4c, 5a, 5b, 5c在有效成分75 g/hm² 剂量下对苘麻、马刺苋、凹头苋等双子叶杂草表现出90%以上的防效.     

New Method of Synthesizing N‐Alkoxycarbonyl‐N‐arylamide with Triphosgene

N‐Chloroformyl‐N‐arylcarbamate, the key intermediate for the synthesis of some excellent pesticides, was synthesized through a new method with triphosgene instead of toxic phosgene. It cannot be obtained through the traditional method using triethylamine as a nucleophile. When triethylamine was replaced by a stronger base, sodium hydride, the product was obtained in good yield.