无溶剂超声辐射下琥珀酸二酰亚胺磺酸铈催化合成5-[(3-吲哚基)-甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物

在琥珀酸二酰亚胺磺酸铈催化下,吲哚、醛和2,2-二甲基-1,3-二噁烷-4,6-二酮在无溶剂条件下超声辐射合成了10种5-[(3-吲哚基)-甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物.当催化剂的用量为3%(摩尔分数)时,30℃反应30~60 min,收率为68.9%~96.7%.此外,还探讨了琥珀酸二酰亚胺磺酸铈的催化机理.该方法具有条件温和,反应时间短且收率高的优点.催化剂邻琥珀酸二酰亚胺磺酸铈对环境友好且可循环利用.     

硼酸催化三组分无溶剂“一锅法””合成5-[(3-吲哚基)-甲基]-2,2-亚丁基-1,3-二噁烷-4,6-二酮衍生物

在硼酸催化下,以吲哚、醛和2,2-亚丁基-1,3-二噁烷-4,6-二酮为原料,经三组分无溶剂条件合成了9种5-[(3-吲哚基)-甲基]-2,2-亚丁基-1,3-二噁烷-4,6-二酮衍生物.当催化剂的用量为5 mol%时,60℃反应30~90 min,收率为68.6%~91.3%.此外,还探讨了硼酸可能的催化机理.该方法具有反应条件温和,反应时间短且收率高的优点.硼酸催化剂对环境友好且可循环利用.     

醋酸铜催化“一锅法”合成5-(1-苯基-3-苯基丙基-2-炔基)-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物

在醋酸铜催化作用下,以抗坏血酸钠为还原剂,以醛、2,2-二甲基-1,3-二噁烷-4,6-二酮和苯乙炔为原料,通过包含Knoevenagel缩合与Conjugate加成反应的多组分反应,有效地合成了10种5-(1-苯基-3-苯基丙基-2-炔基)-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物.该工艺具有收率高(63%～86%)、反应温和、操作简单及环境友好等优点,为合成5-(3-苯基-1-苯基丙基-2-炔基)-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物提供了一种有效的方法.     

无溶剂熔融条件下5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮类化合物的绿色合成

报道了一种基于Yonemitsu反应的β-吲哚衍生物的绿色合成方法.以醛、吲哚和麦氏酸为原料,在无溶剂、熔融的条件下,由微量的水促进三组分反应合成了16种5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮类化合物,产率为55%~94%.该方法具有反应条件温和、操作简单、合成效率高和环境友好等优点.     

无溶剂、无催化剂条件下5-[(3-吲哚基)-芳甲基]-2,2-二甲基- 1,3-二氧六环-4,6-二酮的合成

在无溶剂和催化剂条件下,由芳香醛、吲哚、丙二酸亚异丙酯的三组分缩合反应,制备了5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二氧六环-4,6-二酮,产率为70%～85%,产物结构经1H NMR,IR确证.     

生物介质葡萄糖酸水溶液中5,5-(苯基亚甲基)双(2,2-二甲基二噁烷-4,6-二酮)衍生物的有效合成

在生物介质葡萄糖酸水溶液中,以芳香醛和2,2-二甲基-1,3-二噁烷-4,6-二酮为原料,40℃合成了6种5,5-(苯基亚甲基)双(2,2-二甲基-1,3-二噁烷-4,6-二酮)衍生物.该反应具有收率高(81%~92%)、反应温和、操作简单及环境友好等优点.此外,葡萄糖酸溶液还可重复使用.     

磷酸二氢钾催化Yonemitsu缩合反应合成5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物

以醛、吲哚和麦氏酸为原料,水和乙醇混合液为溶剂,在室温搅拌条件下以磷酸二氢钾为催化剂通过Yonemitsu缩合反应,合成了一系列的5-[(3-吲哚基)-芳甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物,产率为48%~98%,并通过X射线单晶衍射仪测定了化合物4o的晶体结构。 该方法能够有效的促使反应活性较低的4-甲基苯甲醛和4-甲氧基苯甲醛参与反应,以83%和60%的收率获得相应的目标产物,并具有反应条件温和、催化剂廉价易得、后处理简单、产物易于纯化、产率较高等优点,可用于合成3-取代吲哚类化合物。     

无催化剂、水相合成5,5-(苯基亚甲基)双(2,2-亚丁基-1,3-二噁烷-4,6-二酮)衍生物

以芳香醛和2,2-亚丁基-1,3-二噁烷-4,6-二酮为原料,以水为反应介质,无需外加催化剂,通过Knoevenagel缩合与Michael加成的串联反应简单有效地合成了5,5-(苯基亚甲基)双(2,2-亚丁基-1,3-二噁烷-4,6-二酮)衍生物.一系列取代芳香醛被考察,发现该反应具有收率高(63%~83%)、反应温和、操作简单及环境友好等优点.     

酒石酸水溶液中绿色合成5-芳基亚甲基-1,3-二噁烷-4,6-二酮衍生物

在酒石酸水溶液中,以芳香醛和1,3-二噁烷-4,6-二酮为原料,合成了14种5-芳基亚甲基-1,3-二噁烷-4,6-二酮衍生物,收率81%～95%,其中4f, 4g, 5f和5g为新化合物,其结构经¹H NMR, ¹³C NMR和MS(ESI)表征。并对反应条件进行了优化,对反应机理进行了探讨。     

3,3-二甲基-二苯基-2,4-氧杂-8,10-氮杂螺[5.5]十一烷-1,5-二酮-9-硫酮衍生物的有效合成

在分子碘作用下,以芳香醛、硫脲和2,2-二甲基-1,3-二噁烷-4,6-二酮为原料,通过无溶剂三组分缩合反应合成了6种3,3-二甲基-二苯基-2,4-氧杂-8,10-氮杂螺[5.5]十一烷-1,5-二酮-9-硫酮衍生物.当催化剂的用量为10 mol%时,80℃反应3.0~6.0 h,收率为73%~91%.此外,该方法具有反应条件温和、后处理简单且收率高的优点.     

无溶剂硼酸高效合成螺杂双环衍生物

在硼酸催化下,芳香醛、尿素和2,2-二甲基-1,3-二噁烷-4,6-二酮在无溶剂条件下合成了8种螺杂双环衍生物。 当催化剂的用量为10%(摩尔分数)时,80 ℃反应2.0~4.0 h,收率为74%~93%。 此外,还探讨了硼酸可能的催化机理。 该方法具有条件温和,后处理工艺简单及收率高的优点。     

5-取代丙二酸亚异丙酯的结构研究 II: 5-(α-异丙基)-2,2-二甲基-1,3-二氧杂环乙烷-4,6-二酮的晶体结构及量子化学计算

5-(α-异丙基)-2,2-二甲基-1,3-二氧杂环己烷-4,6-二酮C9H14O4, MT=186.21, 正交晶系, 空间群为P212121, 晶胞参数为: a=5.228(1), b=11.079(4), c=16.955埃.V=892.1(5)埃^3, Dc=1.286g.cm^-^3. Z=4, μ(MoKa)=0.92cm^-^1. 用直接法解出结构, 经最小二乘法修正, 最后的偏离因子R=0.062. 结构 测定表明, 分子内六元环具有扭曲船式结构. 对5-(α-苯乙基)-2,2-二甲基-1,3-二氧杂环己烷-4,6-二酮的CNDO/2计算表明, 最稳定构型是扭曲船式结构, 与X射线晶体分析 结果相一致.     

Preparative synthesis of 2,2-dimethyl-5-(trifluoroacetyl)-1,3-dioxane-4,6-dione (2-trifluoroacetyl Meldrum's acid) and 2,2-dimethyl-6-(trifluoromethyl)-4H-1,3-dioxin-4-one and their synthetic usefulness as (trifluoroacetyl)ketene precursors

A simple and reliable method for the preparation of 2,2-dimethyl-5-(trifluoroacetyl)-1,3-dioxane-4,6-dione and 2,2-dimethyl-6-(trifluoromethyl)-4H-1,3-dioxin-4-one on a multigram scale was developed. These (trifluoroacetyl)ketene precursors were used in the hetero-Diels-Alder reaction with dialkylcyanamides and 1-ethoxyprop-1-yne, as well as in some reactions with nucleophiles.     

Investigation of reactions of the organozinc reagents prepared from zinc and dialkyl dibromomalonates with the derivatives of 2-arylmethyleneindan-1,3-dione and 5-arylmethylene-2,2-dimethyl-1,3-dioxane-4,6-dione

Organozinc compounds prepared from dialkyl dibromomalonates and zinc react with 2-arylmethyl-eneindan-4,6-diones, 5-arylmethylene-2,2-dimethyl-1,3-dioxane-4,6-diones, as well as with 2-[4-(1,3-dioxoindan-2-ylidenemethyl)phenyl]methyleneindan-1,3-dione and 5-[4-(2,2-dimethyl-4,6-dioxo-1,3-dioxane-2-ylidenemethyl)phenyl]methylene-2,2-dimethyl-1,3-dioxane-4,6-diones to form dialkyl 3-aryl-1′3′-dioxaspiro(cyclopropane-2,2′-indan)-1,1-dicarboxylates, dimethyl 3-aryl-6,6-dimethyl-5,7-dioxa-4,8-dioxaspiro[2,5]octan-2,2-dicarboxylates, dialkyl 2-{4-[3,3-bis (alkoxycarbonyl)-1′,3′-dioxaspiro(cyclopropane-2,2′-indan)-1-yl]phenyl}-1′,3′-dioxaspiro[cyclopropane-2,2′-indan]-1,1-dicarboxylates, and dialkyl 2-{4-[2,2-bis(alkoxycarbonyl)-6,6′-dimethyl-4,8-dioxo-5,7-dioxaspiro[2,5]oct-1-yl]phenyl}-6,6-dimethyl-4,8-dioxo-5,7-dioxaspiro[2,5]octan-1,1-dicarboxylate respectively.     

A novel solvolytic rearrangement of 2,2-dimethyl-5-(1-Bromomethylethylidene)-1, 3-dioxane-4,6-dione

Treatment of the title compound under basic aqueous conditions leads to 2,2-dimethyl-5-(2-ketopropyl)-1,3-dioxane-4,6-dione; the structure and mechanism of formation of this compound is described.     

New thiourea organocatalysts and their application for the synthesis of 5-(1H-indol-3-yl)methyl-2,2-dimethyl-1,3-dioxane-4,6-diones a source of chiral 3-indoylmethyl ketenes

The stereoselective properties of modified thiourea organocatalysts were tested in the Friedel–Crafts alkylation of indole with 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones, which produces chiral 5-((1H-indol-3-yl)(aryl)methyl)-2,2-dimethyl-1,3-dioxane-4,6-diones. Based on a tentative reaction mechanism for ((S)-N-benzyl-2-(3-(3,5-bis(trifluoromethyl)phenyl)thioureido)-N,3,3-trimethylbutanamide organocatalysts, modifications were applied in four selected regions. Systematic structure-stereoselectivity relationship study allowed designing the best efficient organocatalyst for the investigated Friedel–Crafts alkylation of indole with 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones.     

2,2-Dimethyl-5-(5-R-furfurylidene)-1,3-dioxane-4,6-diones. 3. Selective hydrogenation of the exocyclic double bond and three-dimensional structures of the reaction products

The reaction of 2,2-dimethyl-5-(5-R-furfurylidene)-1,3-dioxane-4,6-diones with sodium borohydride in alcohol leads exclusively to products of hydrogenation of the exocyclic double bond. The three-dimensional structure of one of them — 2,2-dimethyl-5-(5-methyl-furfuryl)-1,3-dioxane-4,6-dioxane — was investigated by x-ray diffraction analysis (XDA).See [1] for Communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1201–1207, September, 1989.     

无外加催化剂条件下芳香醛与活性亚甲基化合物的缩合反应和迈克尔加成反应

在DMF溶剂中，不外加催化剂使芳香醛(1)与2,2-二甲基-1,3-二氧六环-4,6-二酮(2)发生缩合反应生成2,2-二甲基-5-芳亚甲基-1,3-二氧六环-4,6-二酮(3a～f)。在同样条件下，芳香醛与5,5-二甲基-1,3-环己二酮(4)则发生缩合和迈克尔加成反应生成2,2'-芳亚甲基双(3-羟基5,5-二甲基-2-环己烯-1-酮)(5a～h)。用单晶X-射线分析法确定了产物5b的晶体结构。     

Reactions of Bisazomethines of the Naphtalene Series with 1,3-Diketones

Bisazomethines prepared from aromatic dialdehydes and 2-naphthylamine were for the first time reacted with the following diketones: 1,3-cyclohexanedione, 5,5-dimethyl-1,3-cyclohexanedione, 5-phenyl-1,3-cyclohexanedione, indandione, and 2,2-dimethyl-1,3-dioxane-4,6-dione was studied. The reactions with 1,3-diketones of the cyclohexane series yield benzophenanthridine derivatives. The reactions with indandione, depending on conditions, give either bisarylideneindandiones or bisdihydrobenzo[f]indenoquinoline. As evidenced by the ^13C NMR and IR spectra, in the case of biphenyl-4,4'-dicarbaldehyde bis[N-(2-naphthyl)imine] and 2,2-dimethyl-1,3-dioxane-4,6-dione, 4,4'-bis(3-oxo-1,2,3,4-tetrahydrobenzo[f]quinolin-1-yl)biphenyl is formed.     

Three-component condensation of Meldrum’s acid with 2-naphthylamine and esters derived from vanillin

Three-component condensation of Meldrum’s acid (2,2-dimethyl-1,3-dioxane-4,6-dione) with 2-naphthylamine and esters derived from vanillin involves intermediate formation of N-arylmethylidene-2-naphthylamines which are cleaved with Meldrum’s acid to give 5-arylmethylidene-2,2-dimethyl-1,3-dioxane-4,6-diones and arylmethylideneketenes. Reaction of the latter with 2-naphthylamine leads to formation of 2-methoxy-4-(3-oxo-1,2,3,4-tetrahydrobenzo[f]quinolin-1-yl)phenyl carboxylates.