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Dr. Longfei Li Mengxian Dong Prof. Hua-Jie Zhu Prof. Bin Peng Dr. Yaoming Xie Prof. Henry F. Schaefer III 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15628-15633
This mechanistic study demonstrates that an unusual η1-coordinated alkyne complex is critical for the 1-pentyne 1,1-diboration reaction. The comparative studies suggest the “pull–push” antagonistic effect arising from Lewis acidity and steric congestion as the reason for the existence of η1-coordinated alkyne complexes. Analogous η1-coordinated alkene complexes are also predicted and seem to be promising for their application to the important olefin polymerization reaction. 相似文献
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Potential energy surface of HNOS system is investigated by means of MP2 method with 6-311 G(d,p) basis set.The energy for each minimum and saddle point on the potential energy surface is corrected at the QCISD(T)/6-311 G(3df,2p) level of theory with zero-point vibrational energy included.As a result ,eighteen isomers are theoretically predicted and cis-HNSO is found to be global minimum on the potential energy surface,Wherein,fourteen isomers are considered as kinetically stable species,and should be experimentally observed.Comparisons are made for HNOS system with its analogues,HNO2 and NHS2.The nature of bonding and isomers‘ stability of HNOS system are similar to HNS2.The obvious similarities and discrepancies among HNOS,HNO2 and HNS2 are attributed to the hypervalent capacity of sulfur,oxygen and nitrogen atoms. 相似文献
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Guy Bertrand Alain Igau Antoine Baceireco Hansjorg Grutzmacher 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):301-304
Abstract The synthesis and reactivity of he P-bis(diisopropylamino) trimethylsilylphosphaacetylene (bp 75–80°C/10?2) is reported. Addition of trimethylsilyltriflate to this compound leads to a stable methylenephosphonium salt which has been characterized by an X-ray diffraction study. 相似文献
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《Journal of organometallic chemistry》1991,402(3):C50-C55
[Mo(CO)4(η5-C7H9)]+ (1) reacts with acetonitrile to give [Mo(CO)2(NCMe)3(η3-C7H9)]+ (3), which is precursor of a wide reange of η5-cycloheptadienyl complexes [Mo(CO)2L2(η5-C7H9)]+ [6, L = PPH3; 7, L2 = Ph2PCH2PPh2; 8, L2 = 1,3-cyclohexadiene; 9, L2 = 2,2′-dipyridyl]; 9 reacts reversibly with NCMe to give [Mo(CO)2(NCMe)(dipy)(η3-C7H9)]+ (10). 相似文献
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Chun Hong LI Xue Song CHEN Guang Lian ZHOU Zhi Xiang XIE Ying LI? National Laboratory of Applied Organic Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2005,16(8):1024-1026
Marine natural products have received much attention for their attractive structural features and biological activities1. Since the isolation of the moritoside, about 10 related triprenylquinones and hydroquinones were isolated. Some of these natural products exhibit interesting biological effects including inhibit cell division of fertilized starfish eggs2 and anti-HIV3. Triprenylquinone and hydroquinones 1, 2 and 3 were recently isolated from endemic nudibranch Leminda millecra collected i… 相似文献
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In this study, the nine coordination polymers of Fe(III), Co(II) and Ni(II) salts have been synthesized using polyacrylamide (PAA), polt(ethylene glycol) (PEG) and poly(vinyl alcohol) (PVA) and their structures were characterized by magnetic and conductivity measurements, ultraviolet‐visible (UV‐VIS), FTIR spectroscopy and thermogravimetric analysis (TGA). The structures of Fe(III) complexes in the all coordination polymers were found as tetrahedral. The structures of PAA‐Co(II) coordination polymer was determined as octahedral geometry whereas PEG‐Co(II) and PVA‐Co(II) complexes showed as tetrahedral structure. PAA‐Ni(II) and PEG‐Ni(II) complexes have octahedral geometry, whereas PVA‐Ni(II) has a square planar structure. Besides, the stress‐strain experiments of PVA‐metal coordination polymers obtained rubber‐like structure were carried out and the value of breaking‐strain of PVA‐Ni(II) complex was found to be about 17% of vulcanized natural rubber. The conductivities of the resulting polymer‐metal complexes were measured by four‐probe technique and were found in the range 10?5?10?6 Scm?1. Thus, it was suggested that they can be used in the field potential application of conducting polymers. TGA results revealed that among the complexes PEG‐Fe(III) and PVA‐Fe(III) complexes have the highest thermally stable. 相似文献
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Moss RA Wang L Weintraub E Krogh-Jespersen K 《The journal of physical chemistry. A》2008,112(20):4651-4659
p-Nitrophenylchlorocarbene (PNPCC) was studied by laser flash photolysis with UV-vis detection in solution at ambient temperature. The π → p (316 nm) and σ → p (628 nm) absorptions of PNPCC were replaced in π- or O-donor solvents by absorptions due to π- or O-ylidic complexes or O-ylides. Donors included anisole, 1,3-dimethoxybenzene, 1,3,4,5-tetramethoxybenzene, diethyl ether, 18-crown-6, and dibenzo-18-crown-6. Suggestive evidence was also obtained for weak π-complexation of PNPCC by benzene. Computational studies aided in understanding the carbene complex and O-ylide absorption spectra, and they provided structures and energetics for these species. 相似文献
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Potential energy surface of HNS2 is investigated by means of second-order Moller-Plesset Perturbation theory(MP2) and QCISD(T) (single-point)methods,At final QCISD (T)/6-311 G(3df,2p)//MP2/6-311 G(d,p),level with zero-point vibrational energies included,cis-NHSS is found to be global minimum on the potential energy sufrace,followed by low-lying trans-HNSS ,HN(S)S(C2v).cis-HSNS,cis-NSSN,trans-HSNS,trans-NSSN,and HN(S)S(Cs) by 13.46,66.92,78.25,80.38,81.22,81.38 and 86.40 kJ/mol,respectively.A new high-lying HS(N)S isomer with Cs symmetry is located on the potential energy surface ,The kinetic stabilities of all isomers are predicted.Comprisons are made for HNS2 with its analogues,NHO2,HPS2 and HPO2,The causes that lead to the differences between HNS2 and its analogues are hypervalent capacity of phosphorus and distinct electronegativities of hydrogen,nitrogen and phosphorus. 相似文献
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IntroductionPhotorefractive(PR)materialscanbeusedinvariousaPplications,suchasimageprocessing,highdensityopticaldatastorage,opticalinterconnects,andopticalphaseconjugations.However,mostofthereportedPRcomPositesaredopingsystems.ThephaseseparationofcomPonentshaslimitedtheirinvestigation.Toovercomethisdisadvantage,theuseofthemulti-propertieschromophoresmaybeoneoftheeffectiveapproaches.Merocyaninesarenotonlygoodphotoconductivedyes,butalsowidelyusedaschromophoresinnonlinearopticalLBfilmsduetothe… 相似文献
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IntroductionThenitrogen sulfurcontainingcompoundshaveat tractedmuchattentioninthefieldsofpolymericmaterialsandatmospherechemistry .1 4 Andsomeavailableexperi mentalandtheoreticalinformationwasreportedaboutthesecompoundswithH elementorotherfunctionalgroups… 相似文献
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Alexander Shmailov Ludmila Alimbarova Ivan Vatsouro Viktor Tafeenko Elvira Shokova Vladimir Kovalev 《Tetrahedron》2012,68(24):4765-4772
By sulfonation of 3-R-1-adamantylacetic acids 1 with H2SO4 in trifluoroacetic anhydride (TFAA), the previously unknown α-(3-R-adamantyl)sulfoacetic acids 2 were obtained. In the case of 1-adamantylacetic acid 1a, the use of ~1 equiv of H2SO4 led to only 1-adamantylacetic acid 2a, while with an excess of the reactant the hydroxylation of the adamantane tertiary C–H bond also occurred. It is assumed that the bis(trifluoroacetyl)sulfate generated in situ from H2SO4 and TFAA is responsible both for sulfonation and oxidation steps. The adamantylated sulfoacetic acids were used for the preparation of a series of derivatives by modifications of carboxylic, sulfonic acid, and tertiary adamantane OH-groups. Due to the use of TFAA as a medium, a series of derivatives of sulfoacetic acids was obtained directly from acids 1 within one-pot procedures. Some of the synthesized compounds possess anti-HSV activity. 相似文献
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Zhong Hong YAN Chun Hao YANG Xi Han WU Yu Yuan XIEDivision of Chemistry Shanghai Second Medical University Shanghai Sate Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutesfor Biological Sciences Shanghai 《中国化学快报》2004,(4)
The first and facile synthesis of (±)syringaresinol was described. 相似文献
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C Fischer R Thede HJ Drexler A König W Baumann D Heller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(38):11920-11928
Rhodium-η(6) -arene complexes can be generated in the presence of arenes following the hydrogenation of the diolefin in rhodium catalyst precursors of the type [Rh(PP*)(diolefin)]X (PP*=chelating diphosphane, X=noncoordinating anion). In this paper we report the characterization of such arene complexes with the ligands DuPhos, dipamp, dppe, Tangphos, dppf, and diop by means of NMR spectroscopy ((31) P, (103) Rh) and X-ray analysis. A procedure that follows the approach to equilibrium as a function of time monitored by using an UV/Vis diode array was used to determine 20 stability constants. Analyses were accomplished directly from the spectra by either a numeric and/or a new analytic solution of the underlying system of differential equations. Additionally thermodynamic parameters were determined in the temperature range between 278 and 318?K. 相似文献
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《Journal of organometallic chemistry》1989,359(2):C57-C60
N-Substituted dialkynylimines react with η5-cyclopentadienyldicarbonylcobalt to give a mixture of η4-cyclobutadiene cobalt complexes, the structures of which have been determined by X-ray crystallography. 相似文献
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L. N. Novikova N. A. Ustynyuk B. L. Tumanskii P. V. Petrovskii A. A. Borisenko S. V. Kukharenko V. V. Strelets 《Russian Chemical Bulletin》1995,44(7):1306-1310
The oxidation of the carbon-centered [(6-C13H9)Cr(CO)3]– anion (1
–) results in formation of (-6:6-9,9-bifluorenyl)bis-chromiumtricarbonyl (3) due to coupling of the intermediate carbon-centered radical (1.). The oxidation of the metal-centered anion [(5-C13H9)Cr(CO)3]– (2
–), which is isomeric to the 1– anion, gives an equilibrium mixture of the chromium-centered radical {(5-C13H9)Cr(CO)3}. (2
.) and its dimer [(5-C13H9)Cr(CO)3]2 (6). Radical2
. readily reacts with MeI and the solvent (THF); the resulting derivatives, (5-C13H9)Cr(CO)3R (R=Me (10); R=H (7)), undergo fast ricochet inter-ring 56 rearrangements into (6-9R-C13H9)Cr(CO)3 (R=CH3 (9); R=H (4)).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1354–1358, July, 1995.The authors are grateful to D. V. Zagorevskii who recorded the mass spectra. This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-05209) and the International Science Foundation (Grant Nos. MQ 4000 and REV 000). 相似文献
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The mononuclear η5-cyclopentadienyl complexes [(η5-C5H5)Ru(PPh3)2Cl], [(η5-C5H5)Os(PPh3)2Br] and pentamethylcyclopentadienyl complex [(η5-C5Me5)Ru(PPh3)2Cl] react in the presence of 1 eq. of the tetradentate N,N′-chelating ligand 3,5-bis(2-pyridyl)pyrazole (bpp-H) and 1 eq. of NH4PF6 in methanol to afford the mononuclear complexes [(η5-C5H5)Ru(PPh3)(bpp-H)]PF6 ([1]PF6), [(η5-C5H5)Os(PPh3)(bpp-H)]PF6 ([2]PF6) and [(η5-C5Me5)Ru(PPh3)(bpp-H)]PF6 ([3]PF6), respectively. The dinuclear η5-pentamethylcyclopentadienyl complexes [(η5-C5Me5)Rh(μ-Cl)Cl]2 and [(η5-C5Me5)Ir(μ-Cl)Cl]2 as well as the dinuclear η6-arene ruthenium complexes [(η6-C6H6)Ru(μ-Cl)Cl]2 and [(η6-p-iPrC6H4Me)Ru(μ-Cl)Cl]2 react with 2 eq. of bpp-H in the presence of NH4PF6 or NH4BF4 to afford the corresponding mononuclear complexes [(η5-C5Me5)Rh(bpp-H)Cl]PF6 ([4]PF6), [(η5-C5Me5)Ir(bpp-H)Cl]PF6 ([5]PF6), [(η6-C6H6)Ru(bpp-H)Cl]BF4 ([6]BF4) and [(η6-p-iPrC6H4Me)Ru(bpp-H)Cl]BF4 ([7]BF4). However, in the presence of 1 eq. of bpp-H and NH4BF4 the reaction with the same η6-arene ruthenium complexes affords the dinuclear salts [(η6-C6H6)2Ru2(bpp)Cl2]BF4 ([8]BF4) and [(η6-p-iPrC6H4Me)2Ru2(bpp)Cl2]BF4 ([9]BF4), respectively. These compounds have been characterized by IR, NMR and mass spectrometry, as well as by elemental analysis. The molecular structures of [1]PF6, [5]PF6 and [8]BF4 have been established by single crystal X-ray diffraction studies and some representative complexes have been studied by UV–vis spectroscopy. 相似文献
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Thecarbonylationoforganichalides,catalyzedbytransition-metalcomPlexes,isareactionofindustrialinterestleadingtoawiderange0fproductslilieesters,aldehydes,awhdesandacids.Formanyyears,catalyticactivationandfunctionalisationofthecarbonthalogenbondsinorganichalideshavebeenoneofthemostchallengingproblemsanddesirablegoalsforchendsts.Oforganichalides,0rgancchlorideisthemodrmaforeundiDexPdrieerefD1thepeDfu3efulboinboLalindusny.However,because0ftheinertness0ftheirC-Clbonds,organicchloridesexhibitl0wre… 相似文献
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Ecaterina Burevschi Dr. Elena R. Alonso Dr. M. Eugenia Sanz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(49):11327-11333
Non-covalent interactions between molecules determine molecular recognition and the outcome of chemical and biological processes. Characterising how non-covalent interactions influence binding preferences is of crucial importance in advancing our understanding of these events. Here, we analyse the interactions involved in smell and specifically the effect of changing the balance between hydrogen-bonding and dispersion interactions by examining the complexes of the common odorant fenchone with phenol and benzene, mimics of tyrosine and phenylalanine residues, respectively. Using rotational spectroscopy and quantum chemistry, two isomers of each complex have been identified. Our results show that the increased weight of dispersion interactions in these complexes changes the preferred binding site in fenchone and sets the basis for a better understanding of the effect of different residues in molecular recognition and binding events. 相似文献