5-[(3-吲哚基)-甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物的高效合成

在分子碘作用下,以吲哚、醛和2,2-二甲基-1,3-二噁烷-4,6-二酮为原料,通过三组分缩合反应合成了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5%(摩尔分数)时,30 ℃反应60~90 min,收率为71.4%~97.3%。 此外,还探讨了分子碘的催化机理。     

Synthesis, spectroscopic and DFT investigation of dimethyl-2-(5-acetyl-2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-(triphenylphosphinylidene)succinate

Dimethyl-2-(5-acetyl-2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-(triphenylphosphinylidene)succinate has been synthesized and characterized by elemental analysis, FT-IR and ¹H, ¹³C and ³¹P NMR. The vibrational wavenumbers, gauge including atomic orbital (GIAO) ¹H and ¹³C chemical shift values of title compound in the ground state have been computed with density functional theory method (DFT) and the B3LYP functional. The basis sets used are 6-311G(d,p) and 6-31G(d). The harmonic vibrational wavenumbers have been computed and the scaled values have been compared with the experimental FT-IR spectra. The complete assignments have been performed on basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. Most of the computed wavenumbers are found to be in good agreement with the observed spectrum.     

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.     

5-[5-R-furfurylidene]-2,2-dimethyl-1,3-dioxane-4,6-diones 6. Synthesis,structure, and properties of substituted furylimino- and furfurylidenephosphoranes. Molecular and crystal structure of N-[5-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)methyl-2-furylimino(triphenyl)phosphorane

Furylimino- and furfurylidenephosphoranes have been synthesized by sequential conversions of 5-unsubstituted and 5-methylfurfut),Iidetiedio.yanediones. The ylide fragment linked directly with the furfurylidenedioxanedione residue displays strong electron-donating properties, as a result of which resonance occurs in the system of conjugated bonds. The molecular and crystal structure of the iminophosphorane was studied by x-ray structural analysis and the resonance of the bonds in the molecule was confirmed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 335–344, March, 1994.     

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.     

A stereocontrolled route to the synthesis of (±)-3-amino-2,2-dimethyl-1,3-diphenylpropan-1-ol

Both the diastereomers of (±)-3-amino-2,2-dimethyl-1,3-diphenylpropan-1-ol were synthesized starting from a common intermediate, namely, β-hydroxy oxime 6. Diastereoselective reduction with NaBH₄/TiCl₄ and H₂-Pd/C provided syn- and anti-isomers, respectively. Good overall yield and selectivity were realized using a simple protocol.     

2,2-Dimethyl-5-(5-R-2-furfurylidene)-1,3-dioxane-4,6-diones. 4. Synthesis,stereostructures, and properties of thiophene analogs

The reaction of 2-formylthiophenes with Meldrum's acid gave the corresponding thenylidenedioxanediones, which, in contrast to the furfurylidene derivatives, have an s-trans conformation of the mutual orientation of the thiophene ring and the exocyclic double bond. Thenyldioxanediones were synthesized by the selective hydrogenation of the exocyclic double bond.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1338–1342, October, 1989.     

Synthesis of 5-(trifluoromethyl)cyclohexane-1,3-dione and 3-amino-5-(trifluoromethyl)cyclohex-2-en-1-one: new trifluoromethyl building block

A simple synthesis of 5-(trifluoromethyl)cyclohexane-1,3-dione and 3-amino-5-(trifluoromethyl)cyclohex-2-en-1-one from the sodium salt of methyl or ethyl-4-hydroxy-2-oxo-6-(trifluoromethyl)cyclohex-3-en-1-oate is demonstrated. The compounds represent highly functionalized reactive intermediates for the synthesis of organic and heterocyclic compounds containing a trifluoromethyl group.     

Synthesis and fungicidal activities of 1-[(2,2-diaryl-1,3-dioxolan-4-yl)methyl]-1H-azoles

Ketalization of benzophenones with epichlorohydrin or 3-chloropropane-1,2-diol gave 2,2-diaryl-4-chloromethyl-1,3-dioxolanes, which were used to alkylate sodium salts of imid-azole or 1,2,4-triazole. The resulting 1-[(2,2-diaryl-1,3-dioxolan-4-yl)methyl]-1H-azoles exhibit high fungicidal activities. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 940–944, May, 2007.     

A convenient synthesis of 5-(1,2,4-oxadiazol-5-yl)pyrimidine-2,4(1H,3H)-diones

The synthesis of 5-heteroaryl-substituted uracil derivatives is presented. The 1,3-dipolar cycloaddition reaction was applied for the construction of a heterocyclic ring. The nitrile oxides were obtained from the appropriate 4-substituted benzaldoximes using N-chlorosuccinimide (NCS) under basic conditions. [2+3] Cycloaddition of nitrile oxides with 5-cyanouracil as a dipolarophile gave the corresponding 5-(3-substituited-1,2,4-oxadiazol-5-yl)uracils in satisfactory yields under mild conditions. 5-Substituted uracils having an additional heterocyclic ring were obtained as a result of the [2+3] cycloaddition of 5-cyanouracil to nitrile oxides generated from thiophene-2-carbaldehyde and 5-formyluracil derivatives.     

无溶剂、无催化剂条件下5-[(3-吲哚基)-芳甲基]-2,2-二甲基-l,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．     

Synthesis of novel 3-(1,3-thiazol-2-yl)-7,8-dihydroquinoline-2,5(1H,6H)-diones

An efficient method for the synthesis of novel 3-(1,3-thiazol-2-yl)-7,8-dihydroquinoline-2,5(1H,6H)-diones from various 2-dimethylaminomethylidenecyclohexane-1,3-diones, (1,3-thiazol-2-yl)acetonitriles, and dimethylformamide dimethyl acetal was developed. These transformations proceeded through intermediate 2-[2-(4-aryl-1,3-thiazol-2-yl)-2-cyanoethenyl]-3-oxocyclohex-1-en-1-olates. They were isolated as piperidinium salts and used in further heterocyclization reactions with aromatic amines, giving novel 1-aryl-3-(1,3-thiazol-2-yl)-7,8-dihydroquinoline-2,5(1H,6H)-diones. These compounds were also obtained by preparative three-step “one pot” synthesis under controlled microwave irradiation. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 412–417, February, 2008.     

外消旋2-氨基-1-(2,2-二甲基-4H-1,3-苯并二氧芑-6-基)乙醇的拆分研究

以L-二对甲苯甲酰基酒石酸为拆分试剂, 通过化学拆分法得到了旋光异构体(R)-2-氨基-1-(2,2-二甲基-4H-1,3-苯并二氧芑-6-基)乙醇, 产率高且光学纯度大于98% ee.     

“一锅串联法”合成2-[(E)-2-2-氯-1-甲基-3-吲哚基)乙烯基]喹啉-3-羧酸(英文)

设计了以2-(溴甲基)喹啉-3-甲酸乙酯(4)与2-氯-1-甲基-3-吲哚醛(5)为起始化合物,通过简便有效的"一锅法"反应,首次将吲哚环引入2-苯乙烯基喹啉骨架模型,从而得到一新颖结构的双杂环化合物,即(E)-2-(2-(2-氯-1-甲基-1H-3-吲哚基)乙烯基)喹啉-3-羧酸(3),其结构通过波谱数据和元素分析得以证实。     

5-(1,3-Dioxolan-2-yl)-2-furanylzinc bromide; direct preparation, and its application for the synthesis of 5-substituted furan derivatives

5-(1,3-Dioxolan-2-yl)-2-furanylzinc bromide was easily prepared by the direct insertion of active zinc to 2-bromo-5-(1,3-dioxolane)furan under mild conditions. Of interest, the resulting organozinc was successfully coupled with aryl halides and acid chlorides affording the corresponding coupling products in good to excellent yields.     

Base catalyzed intramolecular cyclization of dialkycrotyl(3-alkenylpropyn-2-yl)ammonium salts and aqueous base fission of 2,2-dialkyl-4-methyl-and 2,2-dialkyl-4,6-dimethyl-2,6,7,7a-tetrahydro-1H-isoindolium bromides

Cyclization of dimethylcrotyl(3-vinyl-or-3-isopropenylpropyn-2-yl)ammonium bromides in the presence of base gave a mixture of the isomeric 2,2-dialkyl-4-methyl-and 2,2-dialkyl-4,6-dimethyl-2,6,7,7a-tetrahydro-1H-isoindolium bromides. Basic fission of the salts obtained at increased temperature gave a mixture of the isomeric N,N-disubstituted di-and trimethylbenzylamines whose structures were confirmed by their IR, ¹H NMR, and ¹³C NMR spectra. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 841–846, June, 2008.