首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
1,1′-Diphenyl-3,3′,4,4′-tetramethyl-2,2′,5,5′-tetrahydro-2,2′-biphosphole obtained by reductive dimerization of the appropriate phosphole has been converted into the corresponding 2,2′-biphosphole by P-bromination followed by dehydrobromination of the resulting P,P′-tetrabromo compound with α-picoline. This 2,2′-biphosphole gives two isomeric P-sulfides upon reaction with sulfur, and a Mo(CO)4 chelate upon reaction with Mo(CO)6. Cleavage of the two P-phenyl bonds by lithium in THF yields the corresponding biphospholyl anion, which is converted into a mixture of two isomeric bis(η55-2,2′-diphosphafulvalene)diirons by treatment with FeCl2. The reaction of Mn2(CO)10 in boiling xylene affords a mixture of three complexes, including a (η55-2,2′-diphosphafulvalene)hexacarbonyldimanganese produced by thermal cleavage of the two PPh bonds. Under CO pressure there is a [1,5] P → C shift of the two phenyl groups, leading to formation of (η55-3,3′-diphenyl-2,2′-diphosphafulvalene)hexacarbonyldimanganese.  相似文献   

2.
Summary Starting from the corresponding-chloro carboxylic acids we prepared, -imino dicarboxylic acids and their N- and O- derivatives; the products had the following structures:  相似文献   

3.
4.
A series of BiQuinazolinones bearing either double or triple bonds in their lateral chains have been synthesized. These compounds were then subjected to substrate-controlled reactions such as Diels-Alder, epoxidation and Pauson-Khand reactions. The stereoselective outcome observed in these transformations is very promising for the future application of BiQuinazolinones as chiral auxiliaries.  相似文献   

5.
Mononuclear [M(hfacac)2(H2biim)] complexes, where M = MnII, FeII, CoII, NiII, CuII or ZnII, hfacac = hexafluoroacetylacetonate, H2biim = 2,2-biimidazole; dinuclear K2[M2(acac)4(-biim)] (M = CuII or ZnII) and tetranuclear K2[M4(acac)8( 4-biim)] (M = CoII or NiII) complexes have been prepared and characterized by chemical analysis, conductance measurements, i.r., electronic and e.p.r. spectroscopies and by magnetic susceptibility measurements (in the 2–300 K range). MnII, FeII and CoII are in a high spin state. The e.p.r. spectra of CuII and MnII compounds have been recorded.  相似文献   

6.
7.
Methods have been developed for the synthesis of 2,3′-biquinolines, their 1′,4′-dihydro derivatives, 3-pyrid-2-ylquinolines, and 3-pyrazin-2-ylquinoline based on the interaction of hetarylethylenes and vinyl butyl ether with imidoyl chlorides and Vilsmeier complexes. Using the example of the synthesis of 3-hetarylquinolines and their dihydro derivatives the synthetic possibilities of the Vilsmeier method were shown for creating various bonds in different quinoline nuclei of the bisheterocyclic system. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1209–1215, August, 2008.  相似文献   

8.
9.
10.
Synthesis and antiAIDS, anticancer, antitubercular, fungicidal and antibacterial activities of 2-methyl-4-N-2′-cyanoethyl-N-methane/benzenesulphonylaminobenzaldehyde and their hydrazones are reported.  相似文献   

11.
The reactions of trifluoropyruvates with nitromethane and arylmagnesium bromides leading to trifluoromethyl-containing α-hydroxy acid esters were studied and various derivatives of the acids were obtained.  相似文献   

12.
A convenient synthesis of chiral 3,3′-disubstituted 1,1′-binaphthyl-2,2′-disulfonic acids (BINSA, 1) was developed. The key was directed ortho-lithiation of BINSA methyl ester 2 with n-BuLi and subsequent reaction with an electrophile. Electrophiles such as Br2, I2, Me3SiOTf, and i-PrOB(Pin) reacted smoothly with 3,3′-dilithiated BINSA methyl ester, and the corresponding 3,3′-dihalo-, 3,3′-bis(trimethylsilyl)-, and 3,3′-diboryl-BINSA derivatives were obtained in yields of 21–78%. This simple synthetic method is highly attractive since the ability to prepare 3,3′-disubstituted BINOLs in advance can be useful.  相似文献   

13.
The stability constants of ternary complexes containing copper(II), 2,2′-dipyridyl and a set of mono- and di-substituted malonic acids, were obtained by potentiometric titrations. The results are discussed in terms of substituent influences upon the chelation of the malonic dianions to the system Cu(dip). It is suggested that the electronic and geometric characteristics of the strongest ligand, govern the coordination of the second one.  相似文献   

14.
Russian Chemical Bulletin - Starting from methyl trifluoropyruvate, α-CF3-substituted α-methoxy-α-(furan-2-yl) acetic acids and their derivatives and also methyl...  相似文献   

15.
《Tetrahedron》1988,44(17):5375-5387
Three types of reactions of α-substituted malonates, difluoromethylation, alkylation with n,n,n-trifluoroalkyl sulfonates, and Michael addition to 2-substituted-acrylates, conveniently afforded a number of fluorine containing α amino acids such as β-fluorinated-alanines, 2-amino-n,n,n-trifluoroalkanoic acids, and fluorinated glutamic acids as well as other γ-heteroatom substituted glutamic acids. Here, an efficient enzymatic optical resolution using hog kidney acylase was conducted to obtain both optical isomers of 2-amino-n,n,n-trifluoroalkanoic acids. In addition, a novel sulfoxide rearrangement was observed in a base-catalyzed reaction of diethyl α-difluoromethyl-α-sulfoxymalonates. Finally, α- and γ-substituted glutamic acids obtained were used for chemical modification of the antitumor agent methotrexate to reveal remarkable structure-activity relationships. In particular, the significant effects of fluorine substitution on the in vivo antitumor activity were observed.  相似文献   

16.
17.
18.
19.
By the interaction of L-proline, L-thioproline, pipecolic acid, tetrahydro-1,4-thiazine-3-carboxylic acid, and diastereomeric esters of tetrahydro-1,4-thiazine-3,5-dicarboxylic acid with methyl chloroformate, methyl propiolate, and acetylenecarboxylic acid, we have obtained N-alkoxycarbonyl and N-alkoxycarbonylalkenyl derivatives of -iminocarboxylic acids. By the reaction of N-methoxycarbonyltetrahydro-1,4-thiazine-3-carboxylic acid with hydrazine hydrate, we have obtained 8-amino-7,9-dioxo-4-thia-1,8-diazabicyclo[4.3.0]nonane.For communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1561–1566, November, 1993.  相似文献   

20.
Bis-imines of 2,2′-diaminodiphenylditelluride and 2-tosylamino (9a) and 2-hydroxybenzaldehyde (9b) were prepared and studied by X-ray diffraction, heteronuclear (1H, 13C, 15N, and 125Te) magnetic resonance, and quantum chemical calculations (Pbe1pbe/DGDZVP). According to the X-ray diffraction data, compound 9b in the crystal phase has nonsymmetrical structure: one of the tellurium atoms forms hypervalent bonding with the adjacent oxygen atom, while the second one is not involved in such interaction. The NMR study showed the symmetric molecular structure of imines 9a,b in DMSO-d6 with the tellurium atoms interacting hypervalently with the C=N nitrogen atoms.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号