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1.
Velanganni Paul Alex Raja 《Tetrahedron》2006,62(20):4892-4899
The five-component reaction of ethyl 2-[(2-oxopropyl)sulfanyl]acetate, aromatic aldehydes, and ammonium acetate affords two diastereomers of 5,7-diaryl-5,6,7,8-tetrahydro-1H-pyrido[3,4-b][1,4]thiazin-2(3H)-ones via a novel tandem Mannich-enamine-substitution sequence. Presumably, they are generated from ethyl 2-[(4-oxo-2,6-diaryl-3-piperidinyl)sulfanyl]acetates. During the formation of the trans-5,7-diaryl-5,6,7,8-tetrahydro-1H-pyrido[3,4-b][1,4]-thiazin-2(3H)-ones from ethyl 2-[(4-oxo-2,6-diaryl-3-piperidinyl)sulfanyl]acetates, the configuration at the carbon bearing an aryl group adjacent to the enamide CC double bond is inverted via ring opening and closure. When o-substituted benzaldehydes were employed in this reaction, 5,7-diaryl-5,6-dihydro-1H-pyrido[3,4-b][1,4]thiazin-2(3H)-ones were obtained via air oxidation, along with trans-5,7-diaryl-5,6,7,8-tetrahydro-1H-pyrido[3,4-b][1,4]-thiazin-2(3H)-ones. 相似文献
2.
Fillmore Freeman Choonsun Lee Warren J. Hehre Henry N. Po 《Journal of computational chemistry》1997,18(11):1392-1406
Optimized geometries and total energies for 3,4-dihydro-1,2-dioxin ( 1 ), 3,6-dihydro-1,2-dioxin ( 2 ), 4H-1,3-dioxin (1,3-diox-4-ene, 3 ), and 2,3-dihydro-1,4-dioxin (1,4-dioxene, 4 ) were calculated using ab initio 3-21G, 6-31G*, and MP2/6-31G*//6-31G* methods. The half-chair conformers of 1 (C1), 2 (C2), 3 (C1), and 4 (C2) are more stable than their respective planar structures [ 1 (Cs), 2 (C2v), 3 (Cs), and 4 (C2v)]. Among the four isomers 1 – 4 , the half-chair conformer of 3 is the most stable. It is 53.1, 54.6, and 3.4 kcal mol−1 more stable than 1 , 2 , and 4 , respectively. The largest energy difference (19.0 kcal mol−1) is observed between the half-chair and planar conformers of 2 . The boat conformers of 2 and 4 are less stable than their respective half-chair conformers, but are more stable than their planar structures. Hyperconjugative orbital interactions (anomeric effects) contribute to the greater stability of 3 (nO(3) →σ*C(2)—O(1), nO(3)→σ*,n O(3)→σ*) and of 4 (nO(1)→ σ*). The ab initio calculated structural features of the half-chair conformations of the dihydrodioxins 1 – 4 are compared with the half-chair conformations of cyclohexene and the chair conformations of cyclohexane, oxacyclohexane (tetrahydropyran), 1,2-dioxacyclohexane (1,2-dioxane), 1,3-dioxacyclohexane (1,3-dioxane), and 1,4-dioxacyclohexane (1,4-dioxane) © 1997 by John Wiley & Sons, Inc. J Comput Chem 18 : 1392–1406, 1997 相似文献
3.
Reactions of 3-Z-aroylmethylene-6-chloro-3,4-dihydro-2H-1,4-benzoxazine-2-ones with oxalyl chloride afford 3-aroyl-8-chloro-1,2-dihydro-4H-pyrrolo[2,1-c][1,4]benzoxazine-1,2,4-triones and Z-3-(2-aryl-2-chlorovinyl)-6-chloro-2H-1,4-benzoxazine-2-ones. Aroyl(imidoyl)ketenes generated by decarbonylation of pyrrolobenzoxazinetriones undergo dimerization through [4+2]-cycloaddition to form 4-aroyl-3-aroyloxy-2-(2-oxo-2H-1,4-benzoxazin-3-yl)-1H, 5H-pyrido[2,1-c][1,4]benzoxazine-1,5-diones. 相似文献
4.
V. O. Koz’minykh V. I. Goncharov K. Sh. Lomidze E. N. Koz’minykh 《Russian Journal of Organic Chemistry》2007,43(1):64-67
2-(2-Oxo-2,3-dihydro-1H-indol-3-ylidene)acetic acid esters reacted with benzene-1,2-diamine or 2-aminobenzenethiol to give (2-oxo-2,3-dihydro-1H-indol-3-yl)-substituted 3,4-dihydroquinoxalin-2(1H)-ones or 2H-1,4-benzothiazin-3(4H)-ones. 相似文献
5.
Hidetsura Cho Eunsang Kwon Yoshizumi YasuiSatoshi Kobayashi Shin-ichiro Yoshida Yoshio Nishimura Masahiko Yamaguchi 《Tetrahedron letters》2011,52(52):7185-7188
The first observation of ring cleavage between positions 1 and 2 of a 1,4-dihydropyrimidine skeleton was reported upon the nucleophilic addition of 4,6-unsubstituted 1,4-dihydropyrimidine with 3 equiv of an aniline derivative or phenylhydrazine in the presence of 0.1 equiv of pyridinium p-toluenesulfonate (PPTS) in CH2Cl2; the nucleophilic reactions of 4-methyl-6-unsubstituted 1,6(3,4)-dihydropyrimidine with the same amines gave conventional substituted products at position 2. The effect of this ring opening was found to be due to the electron density of the benzene ring of a nucleophilic amine. On the other hand, aralkylamines, alkylamines, or heterocyclic amines did not cleave the skeleton. The ring-opening chemical structure was confirmed by X-ray crystallographic analysis. This characteristically different phenomenon may be due to the pattern of two CC double bonds of 1,4-DP and 1,6(3,4)-DP as well as to the effect of two substituted groups on the DP ring. 相似文献
6.
The first cyclic unsaturated S-functional derivatives of 4,4-diphenyl-3,4-dihydro-2H-1,4-thiasiline, S-oxide, S,S-dioxide, and S-sulfonimide, were prepared. Oxidation of the hydrolytically less stable 4,4-dimethyl-3,4-dihydro-2H-1,4-thiasiline leads to the corresponding sulfoxide and sulfone along with the ring opening products, siloxanes containing the sulfoxide or sulfonyl group. 相似文献
7.
P. P. Mukovoz V. A. Andreeva O. S. El’tsov E. N. Koz’minykh V. O. Koz’minykh 《Russian Journal of General Chemistry》2015,85(6):1386-1390
Methyl [(3Z)-2-hydroxy-3-(2-oxoalkylidene)-3,4-dihydro-2H-1,4-benzoxazin-2-yl]acetates were prepared by reacting methyl 3,4-dihydroxy-6-oxo-2,4-alkadienoates with 2-aminophenol. 相似文献
8.
Tareq M.A. Al-Shboul Lian Yu Katja Wimmer Helmar Görls Matthias Westerhausen 《Journal of organometallic chemistry》2011,696(1):216-5296
The calcium complex [(thf)4Ca(PPh2)2] (1) is a very effective catalyst for the hydrophosphanylation of substituted alkynes of the type R-CC-R (R = Me, Ph) yielding (E)-1,2-diphenyl-1-diphenylphosphanylethene (2a) and (Z)-1-phenyl-2-diphenylphosphanyl-1-propene (2b). The calcium-mediated hydrophosphanylation of butadiynes of the type R-CC-CC-R (R = Me, SiMe3, Ph, Mes, tBu) proceeds less selectively and diverse products are obtained such as 1,4-substituted 1,4-bis(diphenylphosphanyl)-1,3-butadienes (3), 1,4-diphenyl-1,2-bis(diphenylphosphanyl)-1,3-butadiene (4), and 1,4-di(tert-butyl)-1,4-bis(diphenylphosphanyl)buta-1,2-diene (5). Besides these regioisomers also several configuration isomers with respect to the C=C double bonds [(E)/(Z) isomerism] are obtained. A catalytic cycle can be formulated with the first addition of a Ca-P bond of the catalyst 1 to a CC triple bond always leading to the formation of an intermediate with the newly formed C-P bond in 1-position whereas the remaining phosphanido calcium fragment binds to the carbon in 2-position. The addition of a second diphenylphosphane is much faster and therefore, only two-fold hydrophosphanylated butadiynes are observed. Neither addition products with only one HPPh2 group nor those with more than two PPh2 substituents are obtained. 相似文献
9.
The reactions of vinyl sulfides with -sulfonylvinyl trifluoromethyl ketones afforded CF3-containing 3,4-dihydro-2H-pyrans. An attempt to synthesize 1,1,1-trifluoro-3-(methylthio)but-3-en-2-one resulted in its dimerization into a CF3-containing 3,4-dihydro-2H-pyran. 相似文献
10.
5,6-Dihydrobenz[c]acridines were synthesized by the reaction of 1-chloro-3,4-dihydro-2-naphthaldehyde with aromatic amines under three different conditions:
- a.
- Thermolysis of 1-chlorovinyl-(N-aryl)imines prepared from 1-chloro-3,4-dihydro-2-naphthaldehyde.
- b.
- Acid catalyzed cyclization of 1-(N-aryl)amino-3,4-dihydro-2-naphthaldehydes.
- c.
- Thermolysis of N-arylenaminoimine hydrochlorides derived from 1-chloro-3,4-dihydro-2-naphthaldehyde in DMF medium.
11.
Shuo-En Tsai Wan-Ping Yen Ching-Chun Tseng Jia-Jun Xie Ming Yu Liou Yi-Ting Li Naoto Uramaru Fung Fuh Wong 《Tetrahedron》2018,74(22):2787-2791
The efficient acid catalytic synthesis of pyrazolo [3,4-d]pyrimidine was developed by treating 1H-pyrazol-5-yl-N,N-dimethylformamidine with various aminating agents including N,O-bis(trimethylsilyl)hydroxylamine (NHSiMe3(OSiMe3)), cyanamide (NH2CN), hydroxylamine (NH2OH), methoxyamine (NH2OMe), hydrazine (NH2NH2), and urea (NH2C(O)NH2) in acidic solution at reflux. Based on the experimental result, cyanamide (NH2CN) and methanesulfonic acid were indicated the best aminating agent and acid mediated solvent. On the other hands, the reactivity tendency was involved the activity of original leaving species grafting on the aminating agents, such as –OH, –OMe, –OSiMe3, –NH2, –OSiMe3, –C(O)NH2, and –CN, in acid catalytic heterocyclic reaction. 相似文献
12.
A series of new HgI2 organic polymeric complexes, [Hg2(L1)I4]n (1), [Hg(L2)I2]n (2), [Hg(L3)I2]n (3), [Hg2(L4)I4]n (4), [Hg(L5)I2]n (5), [Hg(L6)I3](HL6) (6) {L1 = 1,4-bis(2-pyridyl)-2,3-diaza-1,3-butadiene, L2 = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene, L3 = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, L4 = 2,5-bis(2-pyridyl)-3,4-diaza-2,4-hexadiene, L5 = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene and L6 = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene} was prepared from reactions of mercury(II) iodide with six organic nitrogen donor-based ligands under thermal gradient conditions using the branched tube method. All these compounds were structurally characterized by single-crystal X-ray diffraction. The HgI2 coordination polymers obtained with the ligands L2, L3 and L5 show one-dimensional zig-zag motifs and in these compounds the HgI2 units are connected to each other by the ligands L2, L3 and L5 through the pyridyl nitrogen atoms. The L1 and L4 ligands in the compounds 1 and 4 act as both a chelating and bridging group. In the compound 6 the ligand L6 acts as a monodentate ligand, resulting form a discrete compound. The thermal stabilities of compounds 1–6 were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). 相似文献
13.
Prakash G. Jagtap Zhiyu Chen Elizabeth Piro Garry J. Southan 《Tetrahedron letters》2009,50(22):2693-2696
Synthesis of potent adenosine A2A and A3 receptor agonist from the modification of adenosine-5′-N-ethylcarboxamide (NECA) has been reported. Diastereoisomer possessing an (R)-3,4-dihydro-2H-pyranyl (DHP) moiety exhibited the highest affinity at the A2A and A3 receptors. The key steps involve the synthesis of (R)-3,4-dihydro-2H-pyran-2-carboxaldehyde (7), which was obtained through the enzyme-catalyzed kinetic resolution of (±)-2-acetoxymethyl-3,4-dihydro-2H-pyran (5). 相似文献
14.
K.R. Kishore Kumar Reddy 《Tetrahedron letters》2008,49(44):6337-6340
Cyclization of 2-[(4-chloroanilino)methyl]phenol (1) with thiophosphoryl chloride afforded 2-chloro-3-(4-chlorophenyl)-3,4-dihydro-2H-1,3,2λ5-benzoxazaphosphinine-2-thione (2). Reaction of 2 with various heterocyclic amines (3) in the presence of Et3N/NaH gave 3-(4-chlorophenyl)-2-nitrogen heterocyclic substituted-3,4-dihydro-2H-1,3,2λ5-benzoxaza-phosphinine-2-thiones (4). Further reaction of 4 with the N-sodium salt of amino heterocyclics in the presence of HCl at 50-60 °C opened the benzoxazaphosphinine ring chemoselectively at the endocyclic P-O bond and yielded 2-[4-chloro(heterocyclic substituted-phosphorothioyl)anilino]methylphenols 5-13. 相似文献
15.
M. Knollmüller 《Monatshefte für Chemie / Chemical Monthly》1971,102(5):1583-1592
Zusammenfassung Bei der Umsetzung des Dinatriumsalzes von 6-Chlor-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazin-2,2-dioxid (1) mit 1,4-Dijodbutan inDMF wurde das erwartete 1,3-Butano-derivat nich erhalten.1 wurde einerseits zu 6-Chlor-4-phenyl-1H-2,1,3-benzothiadiazin-2,2-dioxid (4) dehydriert, andrerseits traten je nach Herstellungsweise des Dinatriumsalzes Methylierungsreaktionen ein bzw. es entstanden 6-Chlor-1-(4-jodbutyl)-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazin-2,2-dioxid (7) und 6,6-Dichlor-4,4-diphenyl-3,3,4,4-tetrahydro-3,3-tetramethylenbis(1H-2,1,3-benzothiadiazin)-2,2,2,2-tetroxid (8).
Herrn Prof. Dr.H. Nowotny gewidmet. 相似文献
Reaction of 6-chloro-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazine-2,2-dioxide with 1,4-Diiodobutane. (Cyclic and bicyclic sulfamides III)
On reaction of the disodium salt of 6-chloro-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazine-2,2-dioxide (1) with 1,4-diiodobutane inDMF the expected 1,3-butano derivative was not obtained. On the one hand1 was dehydrogenated to give 6-chloro-4-phenyl-1H-2,1,3-benzothiadiazine-2,2-dioxide (4), on the other hand according to the method of preparation of the disodium salt either methylation reactions occured or 6-chloro-1-(4-iodobutyl)-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazine-2,2-dioxide (7) and 6,6-dichloro-4,4-diphenyl-3,3,4,4-tetrahydro-3,3-tetramethylenebis(1H-2,1,3-benzothiadiazine)-2,2,2,2-tetroxide (8) were formed.
Herrn Prof. Dr.H. Nowotny gewidmet. 相似文献
16.
P. P. Mukovoz A. V. Gorbunova V. O. Koz’minykh P. A. Slepukhin I. N. Ganebnykh O. S. El’tsov E. N. Koz’minykh 《Russian Journal of Organic Chemistry》2016,52(7):993-999
Methyl 3,4-dihydroxy-6-oxoalka-2,4-dienoates reacted with anthranilic acid hydrazide to give methyl [5-alkyl-1-(2-aminobenzamido)-2-hydroxy-3-oxo-2,3-dihydro-1H-pyrrol-2-yl]acetates. The reaction of anthranilic acid hydrazide with ethyl 3,4-dihydroxy-6-oxohepta-2,4-dienoate afforded ethyl (2Z)-(3a-hydroxy-2-methyl-10-oxo-3,3a,5,10-tetrahydro-4H-pyrazolo[5,1-c][1,4]benzodiazepin-4-ylidene)acetate as solvate with one methanol molecule. The structure of the isolated compounds was determined on the basis of IR and NMR spectra and X-ray diffraction data. 相似文献
17.
N. N. Makhmudiyarova G. M. Kiyamutdinova E. S. Meshcheryakova A. G. Ibragimov U. M. Dzhemilev 《Russian Journal of Organic Chemistry》2016,52(10):1419-1426
An efficient procedure has been developed for the synthesis of 3-aryl-3,4-dihydro-2H-1,5,3-benzodithiazepines, 4-aryl-2,6-dithia-4-azabicyclo[5.3.1]undeca-1(11),7,9-trienes, and 4,10,16-triaryl-2,6,8,12,14,18-hexathia-4,10,16-triaza-1,7,13(1,4)-tribenzenacyclooctadecaphanes by samarium-catalyzed cycloaminomethylation of benzenedithiols with N,N-bis(methoxymethyl)anilines. 相似文献
18.
With the use of KOH/DMSO as the superbase medium, the nucleophilic fluoroarene substitution for CF bonds is presented. The transformation proceeds smoothly with the use of fluoroarenes bearing not only electron-withdrawing group, but also electron-donating group and a variety of nucleophiles such as alcohols, phenols, amines, amides and nitrogen-heterocyclic compounds. The double nucleophilic substitution using ortho-difluoroarenes and nucleophiles bearing ortho-dinucleophilic groups results in the formation of 2,3-dihydro-1,4-benzodioxins, dibenzo[b,e][1,4]dioxins and 10H-phenoxazines in moderate to good yields. 相似文献
19.
The hydrochlorothiazide, 6-chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide-1,1-dioxide, (HCTZ), widely used as a diuretic and anti-hypertensive drug, was transformed into its N-nitroso-derivative, 6-chloro-4-nitroso-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide-1,1-dioxide (ON-HCTZ) by sodium nitrite in an acidic medium. The crystalline complexes of ON-HCTZ with 18-crown-6 (18C6) and cis-anti-cis-dicyclohexyl-18C6 (DCH6B) demonstrated different H-bonding modes from those present in the co-crystals of HCTZ with the same crown ethers. The influence of the nitroso-group on the binding mode and crystal packing is discussed. 相似文献
20.
T. V. Gortinskaya V. G. Nyrkova N. V. Savitskaya M. N. Shchukina 《Chemistry of Heterocyclic Compounds》1971,7(6):698-702
10-Methyl-2-chloro- and 2-chloro-3-methyl-3,4-diazaphenoxazines as well as 2-oxo-3,10-dimethyl-2,3-dihydro-3, 4-diazaphenoxazine were obtained by methylation of 2-chloro-3,4-diazaphenoxazines. Depending on the conditions, alkylation of 2-chloro-3,4-diazaphenoxazine with -diethylaminoethyl chloride gave 1-ethylimidazolino[1,21,2]pyridazo[3,4-b]-1,4-benzoxazine or 2-ethoxy-10-(-diethylaminoethyl)-3,4-diazaphenoxazine. A number of 10-alkyl- and 10-dialkylaminoalkyl-2-chloro-3,4-diazaphenoxazines were obtained by condensation of 3,4,6-trichloropyridazine with substituted o-aminophenols.See [1] for communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 750–754, June, 1971. 相似文献