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1.
2, 7-Diaminothieno[2, 3-d:5, 4-d]dipyrimidine-4, 5(3H, 6H)diones 4 were synthesized by a facile synthetic method, which includes bis-aza-Wittig reaction of bis-iminophosphorane 1 with aromatic isocyanate to give bis-carbodiimide 2 and subsequent reaction of 2 with various dialkylamine in the presence of solid K2CO3 or EtONa.  相似文献   

2.
The reaction of ethyl esters of 4-methyl-2-oxo-2H-l-benzo(naphtho) pyran.3-carboxylic acids (1) with aromatic aldehy-des in the presence of piperidine yielded 4-styryl-3-carboxami-dopiperidyl connmrin derivatives 4. The reaction of hydrazlne hydrate with 1 gave acetophenone hydrozone derivatives 5 and acetophenone azine derivatives 6. The reaction of 1 with prima-ry amines afforded compomlds 7—9. And the treatment of la with Grignard reagents afforded 3-aroyl-4-methyl coumarin derivatives 10.  相似文献   

3.
1,3-Dipolar cycloaddition reactions of ethyl 2-hydropolyfluoroalk-2-enoates (1) with some nitrones were described. The reaction of 3,4-dihydroisoquinoline N-oxide (2) with 1 took place readily in methylene chloride at room temperature to give the corresponding 5-fluoroalkylisoxazolidines regioselectively as a mixture of two diastereoisomers (trans and cis) in high yields, while longer reaction time and higher temperature were needed in the case of non-cyclic nitrones. Under similar conditions the reaction of quinoline N-oxide (14) with 1 did not give the expected adducts and a ring-opening product was obtained.  相似文献   

4.
郑卫红  袁承业 《中国化学》2006,24(9):1170-1174
Reaction of diethyl 2,2-difluoro-3-(a-methylbenzyl)imino-4,4,4-trifluoropropanephosphonate (3) with triethylamine afforded a mixture of normal [1,3]-proton shift reaction product 5 and its HF-eliminated compound 6Z in 1 : 1 ratio. Upon hydrolysis, this reaction mixture gave solely 1,3,3,3-tetrafluoro-2-dioxypropanephosphonate (9). Reaction of 3 with DBU provided only 6, in which the ratio of E/Z forms was dependent on the reaction conditions. Aqueous hydrolysis of 6 led to 9. Catalytic hydrogenation and hydrogenolysis of 6 gave geometric isomers of 11 as expected. The reaction mechanism involved was discussed.  相似文献   

5.
2-Dialkylamino-4(3H)-quinazolinones 4 were rapidly synthesized by a solution-phase parallel synthetic method, which includes aza-Wittig reaction of iminophosphorane 1 with aromatic isocynate to give carbodiimide 2 and subsequent reaction of 2 with various aliphatic secondary amine in a parallel fashion.  相似文献   

6.
Rapid synthesis of 1,2,3,4-tetrahydropyrimidin-2-ones (THPO) from aromatic aldehydes, β-ketoester and urea (or thiourea) using zinc sulfamate as the catalyst under microwave irradiation was described here. Compared with the classical Biginelli reaction, this new method consistently has the advantages of good yields (76%-96%), short reaction time (3-15 min), no corrosion to equipments, ease of manipulation, and low cost catalyst.  相似文献   

7.
Four pyridazinone gluosodes 4 were synthesized by Koenig' s-Knorr reaction of 6-(4-halophenyl)-3 (2H)-pyridazinone silver salt 2 with bromoaeetylglueose 3. Treatment of 4 with dry ammonia at 0 ~ - 5 ℃ effeeted a removal of the acetyl protecting groups to yield compounds 5. When the substituent on the benaene ring was F-or Cl-,O-glueoside was synthesized prineipaUy. However, when the substituent was Br-or I-, N-glueoside was mainly obtained. Their struetures were confirmed by ^1H NMR, IR and elemental analysis.  相似文献   

8.
Novel polycarbonates from 5-allyloxy-1, 3-dioxan-2-one (ATMC) with 5, 5-dimethyl- 1, 3-dioxan-2-one (DTC) were successfully synthesized for the first time using immobilized porcine pancreas lipase (IPPL) as catalyst. The resulting copolymers were characterized by IR, ^1H NMR, ^13C NMR and GPC. The molecular weight (Mn) of the copolymer with molar feed ratio of 10:90 (ATMC:DTC) was 9300 and the polydispersity was 1.31, while the Mn increased to 14300 and polydispersity of 1.25 with the feed ratio of 50:50. Moreover, the composition of the copolymers agreed well with the monomer feed.  相似文献   

9.
Novel diarylethene derivatives: N-substituted-3,4-bisheteroaryl-2,5-dihydropyrroles were synthesized through Mcmurry couple reaction with high yields. The photochromic properties and UV-Vis absorption spectra were studied. The maximal absorptions of their close forms were around at 406 nm or 446 nm, which related mainly with heteroaryl groups but not with substituted groups at nitrogen atom of dihydropyrrole. The absorption of their colored form could be matched with blue light laser.  相似文献   

10.
Highly optically active 4-substituted-2(5H)-furanones 6a-6j were obtained in good yields with de≥98% by the tandem Michael addition/elimination reaction of chiral 3-bromo-2(SH)-furanone (4a), which was conveniently prepared starting from 2-furaldehyde under mild conditions. The products were identified on the basis of their satisfactory elemental analysis and spectroscopic data of IR, UV, ^1H NMR, ^13C NMR and mass spectra. The stereochemistry and absolute configuration of this type of compounds were established by the X-ray crystallographic study. The reaction provided a short and efficient synthesis of the interesting highly optically active 4-subsdtuted-2(5H)-furanones containing an active pyrimidine and a purine base group.  相似文献   

11.
以间二氯苯与氯乙酰氯反应,生成ω-氯代-2,4-二氯苯乙酮(1),再使之分别与3-烷基/芳基-4-氨基-5-巯基-1,2,4-三唑(2a~2l)反应,合成了12种新的3-烷基/芳基-6-(2',4'-二氯苯基)-7H-1,2,4-三唑并[3,4-b]1,3,4-噻二嗪(4a~4l)。利用EA,IR,^1HNMR确定了其结构,并提出该反应的可能机制。  相似文献   

12.
王海山  张致平 《有机化学》1996,16(3):261-266
3, 5, 6-哌嗪三酮-2-甲酰胺(5)经与PCl5-POCl3反应制得3, 5, 6-三氯-2-氰基吡嗪(6)。6经转化为甲酯(7)再水解为3, 5, 6-三氯-2-吡嗪甲酸(8)。由8出发合成了两个2, 3-二氯-5-取代-5, 8-二氢-8-氧-吡啶并[2, 3-b]吡嗪-7-羧酸乙酯(11a~b)。其中5, 7~11均为新化合物, 其组成和结构经元素分析、IR、^1H NMR、MS证实。  相似文献   

13.
The reaction of 5‐(1‐pyrrolyl)‐4‐methyl‐2‐phenylthieno[2, 3‐d]pyrimidine carbohydrazide 5 with CS2 in the presence of pyridine afforded the 6‐(2, 3‐dihydro‐2‐mercapto‐1, 3, 4‐oxadiazol‐5‐yl)‐4‐methyl‐5‐(1‐pyrrolyl)‐2‐phenylthieno[2, 3‐d]pyrimidine 6 , which reacted with methyl iodide in the presence of sodium methoxide to yield the 6‐(2‐methylthio‐1, 3, 4‐oxadiazol‐5‐yl)‐4‐methyl‐5‐(1‐pyrrolyl)‐2‐phenyl‐thieno[2, 3‐d]pyrimidine 7. The 6‐(2‐substituted‐1, 3, 4‐oxadiazol‐5‐yl)‐2‐phenylthieno[2, 3‐d]pyrimidine derivatives 9, 11 and 13 were obtained by the condensation of 6‐(2‐methylthio‐1, 3, 4‐oxadiazol‐5‐yl)‐2‐phenylthieno[2, 3‐d]pyrimidine 7 with appropriate secondary amines. The structure of the new compounds was substantiated from their IR, UV‐vis spectroscopy, 1H NMR, mass spectra, elemental analysis and X‐ray crystal analysis.  相似文献   

14.
Mechanochemical reaction of cluster coordination polymers 1infinity[M3Q7Br4] (M = Mo, W; Q = S, Se) with solid K2C2O4 leads to cluster core excision with the formation of anionic complexes [M3Q7(C2O4)3]2-. Extraction of the reaction mixture with water followed by crystallization gives crystalline K2[M3Q7(C2O4)3].0.5KBr.nH2O (M = Mo, Q = S, n = 3 (1); M = Mo, Q = Se, n = 4 (2); M = W, Q = S, n = 5 (3)). Cs2[Mo3S7(C2O4)3].0.5CsCl.3.5H2O (4) and (Et4N)1.5H0.5K{[Mo3S7(C2O4)3]Br}.2H2O (5) were also prepared. Close Q...Br contacts result in the formation of ionic triples {[M3Q7(C2O4)3](2)Br}5- in 1-4 and the 1:1 adduct {[Mo3S7(C2O4)3]Br}3- in 5. Treatment of 1 or 2 with PPh(3) leads to chalcogen abstraction with the formation of [Mo3(mu3-Q)(mu2-Q)3(C2O4)3(H2O)3]2-, isolated as (Ph4P)2[Mo3(mu3-S)(mu2-S)3(C2O4)3(H2O)3].11H2O (6) and (Ph4P2[Mo3(mu3-Se)(mu2-Se)3(C2O4)3(H2O)3].8.5H2O.0.5C2H5OH (7). All compounds were characterized by X-ray structure analysis. IR, Raman, electronic, and 77Se NMR spectra are also reported. Thermal decomposition of 1-3 was studied by thermogravimetry.  相似文献   

15.
3-(2-Quinolyl)- and 3-(5-carbethoxyfuryl-2)coumarins were prepared by reaction of substituted salicylaldehydes and hetarylacetonitriles. Alkylation and acylation of 3-hetaryl-7-hydroxycoumarins were studied. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 432–434, September–October, 2005.  相似文献   

16.
1INTRoDUCTIONa-Thiocarbonylthioformamidesweresynthesizedin198o[l~2i,however,thereisnoreportofthesecompoundsconcerningtheirpropertiesandreactionactivitiest33.Accordingtotheirstructure,theyseemtohavereactionwithdienophi1es,likesubsti-tutedolefinicandacetylenicdienophilestoleadcorrespondingDiels-Alderproduct.xylene(15ml),diethylbutynedioicester(O.2g,1.2mmol)wasadded,themix-turewasrefluxedfor20h,thencooledtoroomtemperatureandconcentrated.Theresiduewaspurifiedbysilicagelcolumnusingacetone/petr…  相似文献   

17.
Ring Enlargements and Ring Contractions in the Reaction of 1, 3-Oxazolidine-2, 4-diones and l, 3-Thiazolidine-2, 4-dione with 3-Amino-2H-azirines The reaction of 3-amino-2H-azirines 1 and 1, 3-oxazolidine-2, 4-diones 2 in MeCN at room temperature leads to 3, 4-dihydro-3-(2-hydroxyacetyl)-2H-imidazol-2-ones 3 in good yield (Scheme 2, Table 1). A reaction mechanism proceeding via ring enlargement of the bicyclic zwitterion A to give B, followed by transannular ring contraction to C, is proposed for the formation of 3 . This mechanism is in accordance with the result of the reaction of 2a and the 15N-labelled 1a *: in the isolated product 3a *, only N(3) is labelled (Scheme 1). The analogous reaction of 1 and 1, 3-thiazolidine-2, 4-dione ( 5 ) is more complex (Schemes 4 and 5, Table 2). Besides the expected 3, 4-dihydro-3-(2-mercaptoacetyl)-2H-imidazol-2-ones 7, 5-amino-3, 4-dihydro-2H-imidazol-2-ones of type 8 and/or N-(1, 4-thiazin-2-ylidene)ureas 9 are formed. In the case of 2-(dimethylamino)-1-azaspiro[2. 3]hex-1-ene ( 1d ), the postulated eight-membered intermediate 6d could be isolated. Its structure as well as that of 9f has been determined by X-ray structure analysis. A reaction mechanism for the formation of the 1, 4-thiazine derivatives of type 9 is proposed in Scheme 6.  相似文献   

18.
5-Cyano-4,6-dimethyl-2H-pyran-2-one (1) has been prepared via a simple one-pot domino-Knoevenagel reaction starting from ethyl acetoacetate (2) and cyanoacetone (3). Similarly, a new racemic 3-cyano-5-methoxy-4-methyl-5H-furan-2-one (7) has been prepared from 1,1-dimethoxyacetone (6) and cyanoacetic acid (4). The new alkylidene derivatives (Z/E)-ethyl-4-cyano-3-methylbut-3-enoate (5), (Z/E)-ethyl 5-amino-4-cyano-3-methyl-5-oxopent-3-enoate (9), and (2,2-dimethoxy-1-methylethylidene)malononitrile (11) have been prepared via the Knoevenagel reactions. The easy access to these new compounds in good yields shows that ammonium acetate/acetic acid–catalyzed Knoevenagel reactions and domino-Knoevenagel reactions have a broad scope of application.  相似文献   

19.
Depending on the reaction conditions, benzo-2, 1, 3-selenadiazole (I), dichlorodimethyl ether and aluminum chloride react to give a complex IV, or else 4-chloromethyl-(V) or 4, 7-di(chloromethyl) benzo-2, 1, 3-selenadiazole (VI). 5-(II) and 4-methylbenzo-2,l,3-selenadiazole(III) are chloromethylated by dichlorodimethyl ether in the presence of chlorosulfonic acid. Compound II is converted mainly into 5-methyl-4-chloromethylbenzo-2, 1, 3-selenadiazole(VII) or a mixture of three possible isomers VII, VIII, and IX, depending on the amount of base or pseudo-base in the reaction mixture. Ill gives mainly 4-methyl-7-chlorornethylbenzo-2, 1, 3-selenadiazole(X), independent of the presence of base. The structures of the chloromethylation products are shown by reductive splitting to o-diamides, and chromatography of the latter in the presence of reference spots. The high reactivity of the chlorine in the chloromethyl group made it possible to obtain new derivatives by replacing it with a hydroxyl, cyano, or thiocyano group.For Part XL see [1].  相似文献   

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