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1.
Summary Heterobimetallic complexes of the types [Cp2Ti(-EAr)2-M(dppe)] (ClO4)2 [(1)–(4); M, E = Ni, Te (1); Ni, Se (2); Pt, Te (3); Pt, Se (4); Ar = Ph (a), C6H4-4-Me (b), C6H4-4-OMe (c), C6H4-4-OEt (d)] and [Cp2Ti(-TeAr)2-MCl 2] [M = Pd (5), Pt (6)] were obtained by the reactions of Cp2Ti(EAr)2 with M(dppe)(ClO4)2 and M(PhCN)2Cl2, respectively. While (1), (5) and (6) are stable in the solid state as well as in solution, (2)–(4) undergo dissociation to M(dppe)(EAr)2 and Cp2Ti(ClO4)2 in solution, as shown by multinuclear (31P{1H},195Pt{1H}, 125Te{1H}) n.m.r. studies. The reaction of Cp2Ti(SeAr)2 with M(PhCN)2Cl2, however, leads to the formation of Cp2TiCl2 and a polymeric material [M(SeAr)2]
n
. 相似文献
2.
Anju Midha Rajender D. Verma K. Brown R. V. Parish 《Monatshefte für Chemie / Chemical Monthly》1983,114(6-7):661-667
Mixed dialkytin(IV) trifluoroacetates,Me EtSn(O2CCF3)2,Et Pr
n
Sn(O2CCF3)2 andPr
n
Bu
n
Sn(O2CCF3)2 have been prepared by metathetical reactions of the corresponding dialkyltin(IV) chlorides with silver trifluoroacetate in CH2Cl2. They are monomeric in benzene and nonconducting inMeNO2 andMeCN. Bidentate trifluoroacetate groups are indicated by their IR spectra.Mössbauer spectra confirmtrans-arrangement of theR-Sn-R moiety.1H,19F NMR and mass spectra are also discussed.
Gemischte Dialkylzinn(IV)-trifluoracetate
Zusammenfassung Die gemischten Dialkylzinn(IV)-trifluoroacetateMe EtSn(O2CCF3)2,Et Pr n Sn(O2CCF3)2 undPr n Bu n Sn(O2CCF3)2 wurden über Metathese-Reaktionen der entsprechenden Dialkylzinn(IV)-chloride mit Silbertrifluoracetat in CH2Cl2 dargestellt. Sie sind monomer in Benzol und nichtleitend inMeNO2 undMeCN. Die IR-Spektren zeigen zweizähnige Trifluoracetat-Gruppen an. DieMössbauer-Spektren bestätigen dietrans-Anordnung derR-Sn-R-Einheit. Die1H-,19F-NMR und die Massenspektren werden ebenfalls diskutiert.相似文献
3.
Ajay K. Bose Subhendu N. Ganguly Maghar S. Manhas Vaidyanathan Srirajan Ashoke Bhattacharjee Sochanchingwung Rumthao Anju H. Sharma 《Tetrahedron letters》2004,45(6):1179-1181
A novel dinitro secondary metabolite, 2-nitro-4-(2′-nitroethenyl)phenol from a marine source, has been prepared via highly accelerated, microwave assisted, nitration reactions using mild reagents. ipso-Substitution of a carboxy group by a nitro group is discussed. 相似文献
4.
K. L. Baluja Anju Gupta Savita M. Datta 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,28(2):105-108
Configuration interaction wavefunctions, transition energies, line strengths and transition probabilities for allowed transitions within then=2 complex of C-like Fe XXI have been calculated in the LS coupling scheme. We included internal, semi-internal, and all-external types of correlations. We compare our non-relativistic line strengths values with those of relativistic calculations in the Breit-Pauli approximation. The relativistic effects on line strengths are negligible for all transitions except for the transition1 D e →1 D 0. Experimental wavelengths are used in the calculation of transition probabilities. 相似文献
5.
Thangavelu Saravanan Rajendran Selvakumar Mukesh Doble Anju Chadha 《Tetrahedron: Asymmetry》2012,23(18-19):1360-1368
The stereochemical preference of the biocatalyst, Candida parapsilosis ATCC 7330, was investigated with respect to the E/Z configuration in the deracemization and the asymmetric reduction of aryl secondary alcohols and prochiral ketones, respectively. The biocatalyst preferred the E-isomers over Z-isomers as substrates as evidenced from the experimental results of >99% ee and up to 86% isolated yield for E-secondary alcohols. The synthesis of enantiomerically pure E-4-phenylbut-3-ene-1,2-diol (ee >99%, isolated yield 86%) by whole cell mediated deracemization is reported here for the first time. The geometric preference of the enzymes was confirmed by using the cell free extract of this biocatalyst. Mechanistic insights using in silico studies showed that the E-isomers when located in the active site are favourably placed with respect to the catalytic triad (Ser-Tyr-Lys) for hydride transfer from NADPH. 相似文献
6.
Koushik Saha Benson Joseph Rongala Ramalakshmi Dr. R. S. Anju Dr. Babu Varghese Prof. Sundargopal Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7871-7878
Thermolysis of [Cp*Ru(PPh2(CH2)PPh2)BH2(L2)] 1 (Cp*=η5‐C5Me5; L=C7H4NS2), with terminal alkynes led to the formation of η4‐σ,π‐borataallyl complexes [Cp*Ru(μ‐H)B{R‐C=CH2}(L)2] ( 2 a – c ) and η2‐vinylborane complexes [Cp*Ru(R‐C=CH2)BH(L)2] ( 3 a – c ) ( 2 a , 3 a : R=Ph; 2 b , 3 b : R=COOCH3; 2 c , 3 c : R=p‐CH3‐C6H4; L=C7H4NS2) through hydroboration reaction. Ruthenium and the HBCC unit of the vinylborane moiety in 2 a – c are linked by a unique η4‐interaction. Conversions of 1 into 3 a – c proceed through the formation of intermediates 2 a – c . Furthermore, in an attempt to expand the library of these novel complexes, chemistry of σ‐borane complex [Cp*RuCO(μ‐H)BH2L] 4 (L=C7H4NS2) was investigated with both internal and terminal alkynes. Interestingly, under photolytic conditions, 4 reacts with methyl propiolate to generate the η4‐σ,π‐borataallyl complexes [Cp*Ru(μ‐H)BH{R‐C=CH2}(L)] 5 and [Cp*Ru(μ‐H)BH{HC=CH‐R}(L)] 6 (R=COOCH3; L=C7H4NS2) by Markovnikov and anti‐Markovnikov hydroboration. In an extension, photolysis of 4 in the presence of dimethyl acetylenedicarboxylate yielded η4‐σ,π‐borataallyl complex [Cp*Ru(μ‐H)BH{R‐C=CH‐R}(L)] 7 (R=COOCH3; L=C7H4NS2). An agostic interaction was also found to be present in 2 a – c and 5 – 7 , which is rare among the borataallyl complexes. All the new compounds have been characterized in solution by IR, 1H, 11B, 13C NMR spectroscopy, mass spectrometry and the structural types were unequivocally established by crystallographic analysis of 2 b , 3 a – c and 5 – 7 . DFT calculations were performed to evaluate possible bonding and electronic structures of the new compounds. 相似文献
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9.
油楠树脂油化学成分的研究 总被引:2,自引:0,他引:2
采用毛细管气相色谱-质谱(CGC-MS)联用技术对油楠树脂油的化学成分进行研究,共分离出42个峰,并确认了其中39种成分,占总油量的94.31%。分离出的主要成分为蓖麻油酸(17.91%);7,7,8,8-四甲基二环[4.2.0]辛烷-1(6),3-二烯-2,5-二酮(7.60%);1,2-二乙基-3,4-二甲基-苯(6.70%);1,2,6,6-四甲基-1,3-环己二烯(5.35%);n-棕榈酸(4.47%);1,3,4-三甲基-3-环己烯-1-甲醛(4.17%)。 相似文献
10.
Euphorbia species (Family: Euphorbeaceae) have wide applicability in traditional medicines and biofuel sector, and are also rich sources of secondary metabolites, especially terpenoids, attributed with various pharmacological properties. Though 82 Euphorbia species are reported in India, most of the species are uninvestigated for their constituents or potential utilities. Present study reports the isolation and characterization of chemical constituents, estimation of major triterpenoids using a validated HPTLC method and cytotoxicity of plant and latex extracts of Euphorbia trigona. As the secondary metabolites epi-friedelinyl acetate, 3β-friedelinol, taraxerol, rhoiptlenone, stigmasterol and stearic acid were isolated and characterized from E. trigona. HPTLC estimation showed 3β-friedelinol at 0.91 ?± ?0.11% and taraxerol at 1.45 ?± ?0.12% was present in E. trigona plant powder (dry weight). Plant and latex extracts were found non toxic towards normal cell line H9C2 (cardiac myoblasts) and showed insignificant cytotoxic effects towards HeLa (cervical cancer cell line) upto 100 ?μg/ml concentration. 相似文献