Solid state reactions of nitrogenous heterocyclic compounds (Ⅱ)——Solid state reactions of indole with carbonyl compounds

Solid state Michael addition reaction of indole with α,β-unsaturaled carbonyl compounds was carried out,by which a series of compounds containing three different heterocyclic groups binding to one carbon atom were obtained.In the presence of Lewis acid,indole could undergo the solid state condensation reaction with aromatic ketones and aldehydes or quinones.The solid state reaction showed higher selectivity and yield than solution reaction The structures of products were identified by IR,1H NMR,MS,elemental analysis and X-ray crystal analysis.The reaction mechanism was also proposed.     

Solid state reaction of aromatic ketones with heteroaromatics

The solid state reactions of p-nitroacetophenone,acetyl-ferrocene with indole were catalyzed by anhydrous zinc chloride or aluminum chloride,and gave exclusively the 1:2 condensation products.The solid state condensation of aromatic ketones with l-phenyl-3-methyl-5-pyrazolone was also investigated,and the 1:1 and 2:1 condensation products were obtained.The structures of eleven new products were determined by IR,MS,1H NMR and elemental analysis.     

Solid State Photochemistry of Nitrobenzaldehydes

The photochemical reaction of nilrobenzaldehyde with indole and antipyrine was investigated in solid state.The structures of the new products were identified by means of IR,MS,'H NMR and elemental analysis,and the crystal structure of audition product 2c was determined by X-ray diffraction analysis.The mechanism of this reaction was also proposed.     

具有U构型的二{1-甲硫基-1-[1-苯基-1-(1-苯基-3-甲基-5-氧代-4,5二氢吡唑-4-烯)-甲氨基]亚氨甲基}二硫醚的晶体结构

The reaction of 1-phenyl-3-methyl-4-benzoyl-2,5-dihydro-1H-pyrazol-5-one (PMBP) and methyldithiocarbazate (mdtc) in methanol results in formation of a yellow crystalline solid, adduct of 1-phenyl-3-methyl-4benzoyl-2,5-dihydro-lH-pyrazol-5-one and methyldithiocarbazate. When the yellow solids were dissolved in a mixture of methanol and ether (1:4), a red crystal, which is an oxidation product of the former, was obtained by allowing solvent to evaporate for a few days at room temperature. The X-ray analysis of the red crystal indicates that it is a novel disulfide with a special structure like a “U” conformation in the solid state.     

Characterization of A New Organic Photochromic Compound

A new organic photochromic compound, 1-phenyl-3-methyl-4-(4-fluoro)-benzal-5-pyrazolone ethanyl-thiosemicarbazone (PM4FBP-ETSC) was found to undergo photochromic reactions in the solid state. Upon irradiation with 365nm light the white powder sample turned light yellow. The photochromic properties were characterized by the time-dependent UV-vis reflective spectra. The structure of PM4FBP-ETSC was determined by single crystal X-ray diffraction.     

The convenient synthesis of 4-arylmethylidene-4,5-dihydro-3-phenylisoxazol-5-ones

4-Arylmethylidene-4,5-dihydro-3-phenylisoxazol-5-ones were synthesized by the convenient three-component reaction of ethyl benzoylacetate,hydroxylamine and aromatic aldehydes in the presence of pyridine.The target compounds were also obtained by the reaction between 3-phenylisoxazol-5-one and aromatic aldehydes at 105℃under solvent free condition.Yields of products depended considerably on the aldehyde used.     

New Condensation Reaction of β-keto-δ-valerolactones, Carbon Disulfide and Alkyl Halides

β-Keto-δ-valerolactones, which were obtained by reaction of acetoacetate with aldehydes or ketones, reacted with carbon disulfide, alkyl halides and a new condensation reaction was developed. The structures of the products 3 were confirmed by ^1HNMR spectra and elemental analysis.     

Clean Synthesis in Water：Darzens Condensation Reaction of Aromatic Aldehydes with Phenacyl Chloride

The Darzens condensation reaction of aromatic aldehydes with phenacyl chloride proceeded very efficiently in a water suspension medium in the presence of triethylbenzylammonium chloride and only trans-2,3-epoxy-1,3-diaryl-1-propanones were formed which can be isolated simply by filtration.The structures of these compounds were confirmed by elemental analysis,IR and ^1H NMR spectra.Therir configurations are in agreement with that of the same compounds reported in the literature.Compared to the classical Darzens condensation,this new method has the advantages of good yields,high stereoselectivity,low running cost inexpensive and environmentally benign procedure.     

Photochromism of cis(z)-1,2-bispyrryl-substituted ethene derivatives

Photochromism of two bispyrryl-substituted ethenes, 2, 3-bis-(1-p-methoxyphenyl-5-phenyl-2-methyl-3-pyrryl)-2-butene (BPE1) and 2,3-bis(1-p-bromophenyl-4-phenyl-2-methyl-3-pyrryl)-2-butene (BPE2), was studied by laser flash photolysis technique. The results indicate that photocyclization of these compounds proceeds mainly via the excited triplet state, and the cis-trans isomerization proceeds mainly via the excited singlet state. After UV laser pulse irradiation, both photocylization and cis-trans isomerization of BPEl occur, but photocydization is the main reaction. On the other hand, laser photolysis of BPE2 leads mainly to photocydization. The effects of the substituents on the photochromic mechanism are also discussed.     

PEG-OSO3H as an efficient and recyclable catalyst for the synthesis of β-amino carbonyl compounds via the Mannich reaction in PEG-H2O

Sulfuric acid-modified polyethylene glycol 6000（PEG-OSO₃H） was applied as an efficient and recyclable catalyst for the synthesis ofβ-amino carbonyl compounds via the Mannich reaction between aldehydes,aromatic ketones and aromatic amines at room temperature using PEG400-H₂O（1:1） as environment-friendly solvents.The reactions were completed in short times and mild reaction conditions with good to excellent yields.     

Studies on solid state reactions of coordination compounds

A series of tetranuclear Mo(W)-Ag mixed-metal clusters have been synthesized by makinguse of the solid state reactions of[NH_4]_2[MYS_3](M=Mo,W;Y=O,S),AgX(X=Cl,Br,I)and(n-Bu)_4NX'(X'=Cl,Br),two of which[(n-Bu)_4N]_3[MoOS_3Ag_3Br_4](1)and[(n-Bu)_4N]_3[WS_4Ag_3Cl_4](2)have been structurally characterized by X-ray analysis.The crystal data:1,cubic,P 3m,a=12.093(4) ,Z=1,R=0.076;2,cubic,P 3m,a=12.059(2) ,Z=1,R=0.075.The clusteranion core[Ag_3MS_3X']of the two compounds can be viewed as a cube in which the four metal atomsand the four non-metal atoms are statistically distributed,respectively.Substitution reaction withPPh_3 ligand is also discussed for this type of tetranuclear clusters.     

Studies on Enantioselective Effect of Chiral Titanate Reagents on the Synthesis of Substituted Benzhydrols

Chiral titanate reagents were prepared for inducing asymmetric syntheses of substituted benzhydrols from Grignard reagents and aldehydes. The solvents, reaction temperature and exchange of reactants by crossing experiments were investigated. Favorable attack of the nucleophile upon the aromatic aldehydes' prochiral face was proposed, the absolute configurations of the synthesized benzhydrols were suggested, and a preliminary reaction mechanism was described.     

Nucleophilic reactions of 1-methyl-2-methoxy-2-phenyl-3-oxo-2,3-dihydroindole

The title compound (1) was prepared via methylene blue (MB)-sensitized photooxy-genation of l-methyl-2-phenylindole (2d) in methanol. Acid-catalyzed nucleophilic substitution of 1 with nucleophiles gave 1,2,2-trisubstituted 3-oxo-2,3-dihydroindoles (3-6). Reduction of 1 with lithium aluminum hydride, followed by acidic workup yielded 4d and 2d, whereas the same reduction reaction of 1, followed by neutral workup gave l-methyl-2-phenyl-3-hydroxy-2,3-dihydroindole (15), together with 3. The reaction pathways of nucleophilic substitution and reduction of 1 were discussed.     

Synthesis of novel benzo[b]pyrimido[4',5':5,4]thieno[2,3-e][1,6]naphthyridine-8-ones via Pictet–Spengler cyclization

An efficient method for the synthesis of novel benzo[b]pyrimido[4',5':5,4]thieno[2,3e]-[1,6]naphthyridine-8-one derivatives via Pictet–Spengler cyclization is reported. The reaction of 4-(3-aminopyrimido[4,5-d]thieno-2-yl)quinoline-2-ones, which could be obtained from Thorpe–Ziegler isomerization of 4-bromomethylquinoline-2-ones and 5-cyano-1,6-dihydro-4-methyl-2-phenyl-6-thioxopyrimidine,with aromatic aldehydes in the presence of BF_3·OEt_2 gives pyrimidothieno[1,6]naphthyridines in good yields.     

Synthesis and biological evaluation of some novel-3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines

<正>The synthesis of a new series of 3-(5-substituted benzimidazol-2-yl)-5-arylisoxazolines(6a-h) was achieved in excellent yields by the condensation of 1-(1H-benzimidazol-2-yl)-3-(substituted phenyl)prop-2-en-1-ones(5a-h) with hydroxylamine at room temperature.These 1-(1H-benzimidazol-2-yl)-3-(substituted phenyl)prop-2-en-1-ones(5a-h) were obtained by the condensation of 2-acetyl benzimidazoles(4a-d) with different aromatic aldehydes,which in turn were obtained by the oxidation of 2-(α-hydroxy) ethyl benzimidazoles(3a-d) prepared by the reaction of o-phenylenediamines(1a-d) withα-hydroxy propionic acid 2. The synthesized compounds were characterized by their IR,~1H NMR and MS analyses.These compounds were screened for their antibacterial and antifungal activity by standard methods and found some of them active.     

Studies on cyclopent-2-enone——Ⅱ.The diastereoselectivity in Lewis acid mediated reactions of enol silyl ether of cyclopent-2-enone with aldehydes

The aldol reaction of the silyl enol ether of cyclopent-2-enone with aldehydes is mediatedby various Lewis acids.Threo isomers are the major diastereoisomers formed in most cases.A reversediastereoselectivity was observed when the reaction was mediated by TBAF.The results have beendiscussed in detail by structure and transition state analysis.     

Efficient and convenient preparation of N-tosylimines catalyzed by indium trichloride

A new method for preparation of N-tosylimines by InCl₃-mediated condensation of aldehydes with p-toluenesulfonamide in refluxing benzene is reported.The procedure is lauded by its simplicity,mild reaction conditions,excellent yields and adaptability to electron deficient and electron rich aromatic,andα,β-unsaturated aldehydes.     

A New Solution—phase Parallel Synthesis of 2—Alkyamino—3—aryl—5—phenylmethylene—3,5—dihydro—4H—imidazol—4—ones

Thirteen new 2-alkylaminoimidazolones(4) wre rapidly synthesized by a new solution-phase parallel synthetic method,which includes aza-Wittig reaction of iminophosphorane(1) with aromatic isocyanate to give carbodi-imide(2) and subsequent reaction of 2 with various aliphatic primary amine in a parallel fashion.The products were confirmed by ^1H NMR,MS,IR and X-ray crystallographic analysis.The unusual selectivity of the cyclization was probably due to the deometry of the guanidine intermediate.     

Non-Isothermal Crystallization Kinetics of PET Under Solid State Poly condensation

An equation of non-isothermal crystallization kinetics was derived according to a new model and the crystallizations of both the PET samples under solid state polycon-densation and the pre-orientation yarn of high speeding spinning PET were studied with this equation. The results show that there is a good linear relationship between In {-In[1-X(T)]} and lnΦ. The index m in the equation approximately equals to 3 for PET chips and 1. 3 for pre-orientated yarn. At the same temperature, Q(T) decreases with the increase of PET M. W. and the kinetics parameters obtained by Jeziorny' s method indicate that G also decreases with the increase of PET M. W.. Q(T) and Gc show the same varying tendency in the non-isothermal crystallization process.     

ASYMMETRIC SYNTHESIS WITH ORGANO-TITANATE REAGENTS COORDINATED BY TARTARATE-LIKE LIGAND

A series of substituted chiral benzhydrols were synthesized by the reaction of aromatic aldehydes with chiral intermediates formed from chiral titanates and arylmagnesium halides.