锌粉促进三组分“一锅法”合成新型氨基甲酸酯

在金属锌的促进下,以醛、溴代烃和异氰酸酯为原料,THF为溶剂,室温、非催化条件下,通过三组分"一锅法"反应合成了一系列新型的氨基甲酸酯类化合物.该方法具有反应条件温和、操作简单、产率高、原料易得、反应迅速的特点.通过1H NMR,13C NMR,IR,HRMS和元素分析对产物结构进行了表征.     

从α蒎烯一锅合成萜类四氢呋喃衍生物

从α－蒎烯出发，通过臭氧化，硼氢化钠还原剂随后用硫酸处理的一锅法，合成了一个新的萜类四氢呋喃衍生物－２，２－二甲基－３－（反－２－丁烯基）－四氢呋喃３，总收率５５．６％，将α－蒎烯（７８，５１ｍｍｏｌ）的１５０ｍＬ异丙醇溶液冷至－２℃，鼓泡通入含５～６％臭氧的氧气至过量的臭氧从溶液中逸出时止，再通Ｎ２１０ｍｉｎ。于０℃将上述溶液滴加至１００ｍＬ含硼氢化钠（２．５４ｇ，６５ｍｍｏｌ）和氢氧化钠（０．     

"一锅法"合成N-乙基咔唑乙酰化衍生物

以N-乙基咔唑为原料,通过“一锅法”合成了未见文献报道的单乙酰化衍生物3-乙酰基-9-乙基咔唑和双乙酰化衍生物3,6-二乙酰基-9-乙基咔唑,其结构经1H NMR,IR,MS和元素分析表征。     

"一锅法"合成叔胺

以氨基酸甲酯的盐酸盐为原料,用“一锅法”高产率地合成了一系列N-取代叔胺,其结构经1H NMR和MS表征。     

"一锅法"合成戊二烯甲酯

以丙烯醛和丙二酸为原料,经缩合反应制得戊二烯酸,产率52．2％。采用“一锅法”合成了戊二烯酸甲酯,产率52．8％。其结构经^1H NMR和IR确证。     

新型糖氨基酸类化合物的合成研究

糖氨基酸(sugar amino acids, SAAs)是一类同时含有氨基和羧基的糖类衍生物, 具有糖和氨基酸的结构特征和化学反应特性, 常作为多功能合成砌块用于组合化学的研究、糖模拟物和多肽模拟物的构建等. 因此, 该类化合物的设计与合成受到国内外化学家的持续关注. 在本文中, 我们发展了一种简单、高效的合成新型糖氨基酸的方法, 从廉价易得的3,4,6-O-三乙酰基-D-葡萄糖烯和3,4,6-O-三乙酰基-D-半乳糖烯出发, 在硝酸铈铵(CAN)的作用下通过一步自由基加成反应分别得到2-C-二羧酸酯类化合物gluco-2和galacto-2, 再经过脱羧、脱乙酰、碘代、叠氮化钠取代和一锅法还原氨化反应, 以最短直线步骤6步实现了糖氨基酸gluco-7(总收率34%)和galacto-7(总收率19%)的合成. 所有合成的化合物均经过IR, ¹H NMR, ¹³C NMR和HRMS的表征.     

一锅合成法的新进展

综述了最近十余年一锅合成法在有机合成中的主要应用及新进展。参考文献４７篇。     

偶联试剂SMCC的一锅法合成

SMCC是一类含有N-羟基琥珀酰亚胺(NHS)活性酯和马来酰亚胺的双功能偶联剂,可以分别将含有巯基和氨基的化合物键接在一起,在生物及化学领域应用广泛。本文采用一锅法将反式氨甲环酸、马来酸酐在DMF作溶剂的条件下反应生成反式氨甲环酸的马来酰胺,再与三氟乙酸酐、N-羟基丁二酰亚胺、三甲基吡啶等反应生成SMCC,对合成SMCC的工艺进行了简单优化,得出了最佳合成条件,总收率可达92%,纯度可达99%以上。     

DABCO催化的"一锅法"水相合成苯并色烯衍生物

以1,4-二氮杂二环[2.2.2]辛烷(DABCO)为催化剂,采用"一锅法"水相合成了一系列苯并色烯衍生物,收率26%～95%,其结构经1H NMR,13C NMR和MS确认.     

无溶剂一锅法合成1,4-二氢吡啶

碳酸氢铵、醛和1, 3-二羰基化合物于70 ℃无溶剂条件下缩合以86～97%的产率得到1, 4-二氢吡啶.     

Stereoselective Synthesis of 2-Deoxythiosugars from Glycals

2-deoxythiosugars are more stable than 2-deoxysugars occurring broadly in bioactive natural products and pharmaceutical agents. An effective and direct methodology to stereoselectively synthesize α-2-deoxythioglycosides catalyzed by AgOTf has been developed. Various alkyl thiols and thiophenols were explored and the desired products were formed in good yields with excellent α-selectivity. This method was further applied to the syntheses of S-linked disaccharides and late-stage 2-deoxyglycosylation of estrogen, L-menthol, and zingerone thiols successfully.     

微波辐射下1-氨基烷基膦酸酯的一锅合成

以醛、胺及膦酸二乙酯为原料,微波辐射3min～5min,高产率地一锅合成了一系列的1．氨基烷基膦酸酯。其结构经^1HNMR,IR和元素分析表征。     

Zinc-N-Base Mediated Synthesis of Pyranoid Glycals Mechanistic Studies

Abstract

Reactions of acetobromoglucose 1 or acetylated 1-bromo-D-galactopyranosyl cyanide 3 with zinc dust in the presence of a N-base (1-methylimidazole, 4-methylpyridine, or triethylamine, pyridine, respectively) in ethyl acetate or benzene were efficiently inhibited by 10–30 mol % of 1,4-dinitrobenzene, elemental sulfur, or carbon tetrachloride. Presence of glycosyl radicals in these reactions was also shown by trapping them with tert-dodecyl mercaptan or methyl acrylate. Based on these observations and the high yielding formation of glycal derivatives 2 and 4 of high purity a free radical chain mechanism is proposed for the transformations.     

Multicomponent One-pot Diastereoselective Synthesis ofBiologically Important Scaffold under Microwaves

A simple and fast three-component diastereoselective synthesis of biologically important spiro scaffold 4 wascarried out in reasonable purity starting from readily available 1H-indole-2,3-dione 1,ethyl cyanoacetate 2 and4-hydroxycoumarin 3 under microwave in high yield(88%-92%)and short time.     

An Improved Synthesis and NMR Spectra of Benzylated Glycals

Abstract

Benzylated glycals, unlike their acylated congeners which easily undergo allylic rearrangement, are frequently employed as reactive enol ether type substrates in a variety of electrophilic addition reactions.^1–4 Although these compounds are considered to be readily available substrates, reported procedures for their syntheses involve some steps of limited efficiency, chromatographic separations or costly reagents,^5–7 and experimental requirements not amenable for large scale preparations. In view of the recent applications of benzylated glycals to syntheses of O-glycosides,^1,2 C-glycosyl compounds,³ and β-lactams,⁴ we have undertaken a study aimed at efficient one step benzylation procedures applicable to pyranoid 1-enitols as well as to their acylated derivatives. This goal was eventually achieved by employing a catalytic phase transfer alkylation system with     

微波辐射下一步合成9-芳基-1,2,3,4,5,6,7,8,9,10-十氢-1,8-吖啶二酮

以芳醛、1,3-环己二酮、醋酸铵为原料在无溶剂条件下经微波辐射合成了一系列9-芳基-1,2,3,4,5,6,7,8,9,10-十 氢-1,8-吖啶二酮. 该反应的反应时间短、产率高、环境友好、后处理方便. 产物的结构经红外光谱、核磁共振谱表征, 3d的结构经单晶X射线衍射进一步确证.     

meso-三嗪取代苯基卟啉的简单一锅合成

报道一种以羟基卟啉与三嗪和其它亲核试剂为原料一锅法高产率合成不对称多取代三嗪卟啉化合物的简单方法. 研究了2,4,6-三氯三嗪与羟基卟啉、醇和胺通过分级亲核取代反应合成不对称2,4,6-取代三嗪卟啉的方法和反应条件. 以2,4,6- 三氯三嗪和5-(4-羟基)苯基-10,15,20-三苯基卟啉反应生成卟啉单取代二氯三嗪, 然后进一步与醇或胺反应合成了7个三嗪卟啉新化合物, 产物经元素分析, MS, 1H NMR和UV-Vis进行结构表征.