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1.
It is shown that the cross product t
I
J
( R
x
)≡ g
I
J
( R
x
)× h
I
J
( R
x
), where g
τ
I
J
( R)=( c
I
( R
x
)− c
J
( c
I
( R
x
)+ c
J
( R
x
)), h
τ
I
J
( R)= c
I
( R
x
) †
c
J
( R
x
), τ is an internal nuclear coordinate, the c
I
( R) satisfy [ H( R)− E
I
( R)] c
I
( R)= 0 and H( R) is the electronic Hamiltonian matrix, is a unique property of a conical intersection at R
x
. t
I
J
( R
x
)=0 when R
x
is located at the intersection of two (or more) seams of conical intersection. This criterion for an intersection of two
seams of conical intersection has important implications for algorithms that seek to locate such points. Here it␣is␣used to
analyze the trifurcation of a generic C 2v
2S+1
A− 2S+1
B seam of conical intersection, analogous to those recently found in AlH 2 and CH 2.
Received: 31 July 1997 / Accepted: 27 August 1997 相似文献
2.
New organotin(IV) carboxylates, R 2SnL 2 (R= n-Bu: 1), R 2Sn(Cl)L (R= n-Bu: 2), and R 3SnL (R=Me: 3; n-Bu: 4; Ph: 5) have been synthesized by stirring 5-chloro-2-hydroxybenzoic acid HL with KOH and R 2SnCl 2 (R= n-Bu)/R 3SnCl (R=Me, n-Bu, Ph) in methanol at room temperature. The complexes along with ligand have been characterized by FTIR, ( 1H, 13C) NMR, EI-MS, and single-crystal XRD crystallography. FTIR data indicated bidentate coordination of carboxylate. NMR data suggested six- or five-coordinate geometry of organotin(IV) carboxylates. Single-crystal XRD of 1 demonstrated skew-trapezoidal geometry around the tin center, with the basal plane occupied by four oxygens and the two butyl groups lying in distorted axial position. Complexes 1, 2, and 5 exhibited interaction with SS-DNA (salmon sperm) and suggests intercalating mode of binding. The complexes displayed significant antimicrobial activities against bacterial and fungal strains as compared to free ligand. The hemolytic activity of the complexes was lower compared to Triton-X 100 (positive control, 100% lysis) and higher than phosphate-buffered saline (negative control, 0% lysis). Complex 4 was the most potent inhibitor of bacterial/fungal growth. 相似文献
3.
The addition of ·P(O)(OPr i) 2 (R 1), ·CMe 3 (R 2), and ·CCl 3 (R 3) radicals to metallofullerenes (η 2-C 60)IrH(CO)(CNBu t) 2( o-HCB 10H 9CCH 2PPh 2-B,P) ( 1), (η 2-C 60)IrH(CO)(DIOP) (DIOP is (4 R,5 R)-(+)-4,5-bis(diphenylphosphinomethyl)-2,2-dimethyl-1,3-dioxolane, 2), and (η 2-C 60)IrH(CO)(PPh 3) 2 ( 3) was studied by EPR spectroscopy. A stability study of spin adducts (SAs) of R 1 radicals with complexes 1 and 2 showed that when the reactions are initiated by illumination with 366-nm light, the EPR spectra exhibit only signals of those
isomers that are formed upon attack of the R 1 radicals on the carbon atoms of the cis-1 and cis-2 bonds ( i.e., carbon atoms of the fullerene hemisphere to which the metallofragment is attached). Investigations of the reactions of R 2 and R 3 radicals with complexes 1–3 initiated with 366-nm light made it possible to detect (i) regioisomers formed by adding these radicals to carbon atoms of
the cis-n bonds and (ii) SAs formed by adding the radicals to carbon atoms of other bonds in complexes 1–3. The hyperfine structure of the EPR spectrum essentially depends on the spatial structure of substituents at the metal atom
and allows individual regioisomers of not only phosphoryl radicals, but also carbon-centered radicals R 2 and R 3 with metallofullerenes 1–3 to be identified. The rate constants for addition of R 2 and R 3 radicals to complexes 2 and 3 were determined.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1302–1309, July, 2007. 相似文献
4.
The green colored trithiocarbamato complexes of dirhenium(III,III) of type [Re2(μ-η2-SLR)2(η2-LR)3][ReO4] (4(LR)), where LR represents the dithiocarbamato ligands [LR?=?S2CNEt2, 4(LEt) and S2CN(CH2)4, 4(LPyr)], have been synthesized in moderate yield by reacting Re2(μ-O2CCH3)4Cl2 (1) and sodium salt of diethyldithiocarbamate or pyrrolidinedithiocarbamate in boiling ethanol under nitrogen atmosphere. The spectral (IR, UV–vis, NMR) and electrochemical properties of the complexes are reported. The identity of complex 4(LEt) has been established by single-crystal X-ray structure determination. The density functional theory (DFT) calculations rationalized the electronic structure of complexes 4(LR) in comparison with dithiocarbamato complexes of dirhenium(II,II) and dirhenium(III,II). The absorption spectra of the 4(LR) complexes are scrutinized by the time-dependent DFT analysis. 相似文献
5.
采用间苯二(取代水杨醛酰腙)(H 4L)与R 32SnOH溶剂热反应,或间苯二甲酰肼、3-叔丁基水杨醛和三环己基氢氧化锡一锅溶剂热法反应,合成了4个新的有机锡配合物(SnR 2) 2L( 1~ 4),其中,H 4L= m-Ph(CONH—N=CH( o-OH) PhR 1) 2;R 1=NEt 2,R 2=Ph( 1);R 1=3,5-di- tert-butyl=3,5- t-2Bu,R 2=Ph( 2);R 1=3,5- t-2Bu,R 2=Cy( 3);R 1=3- tert-butyl=3- t-Bu,R 2=Cy( 4)。经元素分析、红外光谱和( 1H、 13C、 119Sn)核磁共振谱表征,并用X射线衍射方法确证配合物 1~ 4的结构。配体H 4L的2个取代水杨醛酰腙链向内取向并与锡原子配位形成3个内向 E型配合物 1~ 3,取代水杨醛酰腙链向外取向并与锡原子配位形成外向 E型配合物 4。配合物 1、 2和 4属于三斜晶系 P1空间群,配合物 3属于单斜晶系 P2 1/ c空间群。中心锡与配位原子构成畸形双角三锥构型。配体、配合物-三氯甲烷溶液的荧光性能表明,当具有弱荧光的配体 m-Ph(CONH—N=CH( o-OH) PhNEt 2) 2(H 4L 1)和无荧光的配体 m-Ph(CONH—N=CH( o-OH) Ph(3,5- t-2Bu)) 2(H 4L 2)分别与苯基锡、环己基锡配位后,配合物-三氯甲烷溶液发出强荧光。 相似文献
6.
Four new polyoxometalate compounds consisting of Anderson-type anions and trivalent rare earth (RE) cations, [R E 2 (H 2O) 14M(OH) 6Mo 6O 18][M(OH) 6Mo 6O 18]?·?14H 2O, R E?=?Y, M?=?Cr( 1), Al( 2); R E?=?Yb, M?=?Al( 3), Cr( 4), have been synthesized in aqueous solution and characterized by elemental analyses, infrared (IR) spectra, thermal gravimetric (TG) analyses, and single crystal X-ray diffraction. [M(OH) 6Mo 6O 18] 3? as a bidentate ligand coordinates to two R E 3 + , forming a double-supported cation [R E 2(H 2O) 14M(OH) 6Mo 6O 18] 3+. The cations and other [M(OH) 6Mo 6O 18] 3? anions in the crystals are linked via hydrogen bonding interactions tightly, forming four supramolecular compounds. The magnetic properties of 1, 3, and 4 have been examined by measuring their magnetic susceptibilities from 2 to 300?K. 相似文献
7.
Four new μ2-oxo-bridged dinuclear aryltelluronic triorganotin esters [ArTe( μ-O)(OH)(OSnR 3) 2] 2 (Ar?=? n-propyl-Ph, R?=?Me: 1, R?=?Ph: 2; Ar?=? i-propyl-Ph, R?=?Me: 3, R?=?Ph: 4) were synthesized by reaction of μ2-oxo-bridged dinuclear aryltelluronic acids and the corresponding R 3SnCl ( R?=?Me, Ph) with potassium hydroxide in methanol. The complexes were characterized by X-ray crystallography, elemental analysis, FT-IR, and NMR ( 1H, 13C, 119Sn) spectroscopy. The structural analysis indicates that these complexes are isostructural and crystallized as Sn 4Te 2 molecules, in which the asymmetric four-membered Te 2( μ2-O) 2 units are situated in the center. The geometry of tellurium is described as a distorted octahedron and each tin is described as a distorted tetrahedron. Complex 2 has a 2-D network structure connected by intermolecular C–H?π interactions. Complexes 1–4 were tested for in vitro cytotoxicity against human lung cancer cells (A549) and human hepatocellular carcinoma cells (HepG2). 相似文献
8.
Abstract The synthesis of octahedral complexes [SnCl 4L 2] (L = R 2NP(O)(OCH 2CF 3)(O-p-tolyl): R 2N = Me 2N ( 1), Et 2N ( 2), CH 2(CH 2CH 2) 2N ( 3), and O(CH 2CH 2) 2N ( 4), or L = R 2NP(O)(OCH 2CF 3)(O-p-PhNO 2): R 2N = Me 2N ( 5), Et 2N ( 6), and O(CH 2CH 2) 2N ( 7) is described. The new adducts have been characterized by multinuclear ( 31P, 19F, 119Sn) NMR, IR spectroscopy, and elemental analyses. The solution NMR data show the presence of a mixture of cis and trans isomers. The structure of the complexes in solution was further confirmed by 119Sn NMR spectra, which display a triplet for each isomer, indicating an octahedrally coordinated tin center. The effects of the nature of R and Ar substituents on the donor ability of the P=O group in the ligands R 2NP(O)(OCH 2CF 3)(OAr) were investigated on the basis of 119Sn NMR chemical shifts and used to classify these ligands according to their Lewis basicity. 相似文献
9.
通过乳酸衍生物和3-溴-4-羟基苯甲酸的组合得到对映体3-溴-4-(((1R)-1-羧基乙基)氧基)苯甲酸(R-H 2bba)和3-溴-4-(((1S)-1-羧基乙基)氧基)苯甲酸(S-H 2bba)。以其为手性合成子在水热条件下分别与1,3-二(吡啶-4-基)丙烷(1,3-dpp)和Ni 2+反应,构建了对映手性配位聚合物{[Ni(R-bba)(1,3-dpp)(H 2O) 0.5]·1.5H 2O} n(HU12-R)和{[Ni(S-bba)(1,3-dpp)(H 2O) 0.5]·1.5H 2O} n(HU12-S)。结构分析揭示HU12-R和HU12-S是具有dia网络特征的三维螺旋骨架。在骨架中,阴离子配体R-bba 2-和S-bba 2-分别与Ni 2+中心连接在一起围绕2,螺旋轴得到一对小的对映螺... 相似文献
10.
通过乳酸衍生物和3-溴-4-羟基苯甲酸的组合得到对映体3-溴-4-(((1 R)-1-羧基乙基)氧基)苯甲酸( R-H 2bba)和3-溴-4-(((1 S)-1-羧基乙基)氧基)苯甲酸( S-H 2bba)。以其为手性合成子在水热条件下分别与1,3-二(吡啶-4-基)丙烷(1,3-dpp)和Ni 2+反应,构建了对映手性配位聚合物{[Ni( R-bba)(1,3-dpp)(H 2O) 0.5]·1.5H 2O} n ( HU12-R)和{[Ni( S-bba)(1,3-dpp)(H 2O) 0.5]·1.5H 2O} n ( HU12-S)。结构分析揭示 HU12-R和 HU12-S是具有 dia网络特征的三维螺旋骨架。在骨架中,阴离子配体 R-bba 2-和 S-bba 2-分别与Ni 2+中心连接在一起围绕2 1螺旋轴得到一对小的对映螺旋链,而1,3-dpp与Ni 2+中心则围绕4 1螺旋轴构建出另外一对大的对映螺旋链。电化学测试显示 HU12-R属n型半导体,具有低阻抗性质,对紫外可见光有很强的吸收能力。进一步光催化实验证实在紫外光照射下所得配合物对染料降解有明显催化效果。 相似文献
11.
Three chiral complexes: [M(( R, R)-et-pybox)Cl 2] (M=Zn, 1, and Mn, 2) and [Ni(( R, R)-et-pybox)(H 2O) 2Cl]Cl ( 3) (( R, R)-et-pybox is C 2-symmetric 2,6-bis[4′-( R)-ethoxyoxazolin-2′-yl]pyridine) have been synthesized and characterized by elemental analysis, IR, UV, TG and single-crystal
X-ray diffraction. Single-crystal X-ray diffraction analyses show that 1 is isostructural to 2, the obtained complexes are of isolated mononuclear and the metal atoms of 1 and 2 have distorted trigonal bipyramidal coordination environment. A feature of interest is noted in the unit cell of 3, there exist two types of molecules, which similarly have a distorted octahedral geometry but only slightly differ in the
orientation of the coordinated atoms to the central Ni atom. These two types of molecules interact with each other by O–H···Cl
hydrogen bonds, giving rise to one-dimensional ribbon structure. 相似文献
12.
Methods were developed for synthesizing the 3-Carene derivative (1 R)-1-|(1 R,2 R,5 R)-2-benzyl-3-imino-6,6-dimethylbicyclo[3.1.0]hex-2-yl}-ethanol (HL) and stable copper(II) complexes [Cu 2(H 2O)L 2(CH 3COO) 2] · H 2O ( IV), [Cu 2L 2Cl 2] ( V), and [Cu 2L 2Br 2] ( VI). According to X-ray diffraction data, IVand Vhave molecular binuclear structures with a planar Cu 2O 2cycle. The CuOCu angles are equal to 102.2°, 102.8° ( IV) and 103.2°, 103.8° ( V). The L –terpene ligand acts as a tridentate cyclic bridge. A strong antiferromagnetic exchange interaction between the unpaired electrons of the copper(II) ions was detected in compounds IV– VIusing the static magnetic susceptibility method. The –2 Jparameter for IV, V, and VIis equal to 660, 1000, and 1060 cm –1, respectively. 相似文献
13.
Chiral aminoalcohol based Schiff bases ( R or S)-2-{(E)-(2-hydroxy-1-phenylethylimino)methyl}phenol and ( R/ S)-2-{(E)-(2-hydroxy-2-phenylethylimino)methyl}phenol coordinate to copper(II)acetate to give enantiopure Λ/Δ- or Δ/Λ- bis[( R or S)-2-{(E)-(2-hydroxy-1-phenylethylimino)methyl}phenoxide-κ 2N, O]copper(II), {Λ/Δ-Cu( R-L1) 2 ( 1) or Δ/Λ-Cu( S-L1) 2 ( 2)}, and racemic Δ/Λ- and Λ/Δ- bis[( R/ S)-2-{(E)-(2-hydroxy-2-phenylethylimino)methyl}phenoxide-κ 2N, O]copper(II), {Δ/Λ- and Λ/Δ-Cu( R/ S-L2) 2 ( 3)}, respectively. The complexes are characterized by elemental analyzes, IR, UV–Vis, polarimetry, circular dichroism (CD), differential scanning calorimeter (DSC), and mass spectroscopy. Polarimetry shows the rotation to the left at ?113.6° ( 1) and to the right at +106.4 o ( 2). CD spectra show the expected mirror-image relationship with opposite sign of ellipticity maxima (Δ εmax = +0.43 for 1 and ?0.42 M ?1 dm 3 cm ?1 for 2 at 638 nm) due to the d-d transitions of the metal ion. CD spectral analyzes further reveal a diastereoselectivity or diastereomeric excess towards Λ-Cu( R-L1) 2 or Δ-Cu( S-L1) 2 configuration for 1 or 2 in solution. Similarly, the enantiomeric pair of Δ-Cu( R-L2) 2 and Λ-Cu( S-L2) 2 configurations (CD inactive) for 3 will be preferred in solution. Electronic spectra in different solvents reveal a negative solvatochromism by shifting absorption maxima of the MLCT band to higher energies in solvents of increasing polarity as well as acceptor number. DSC analyzes show an endothermic peak at 525.5 ( 1) or 528.7 K ( 2), corresponding to a thermally induced structural phase transformation from distorted square-planar to regular tetrahedral. 相似文献
14.
The reactions of phenylphosphonic acid [(OH) 2POC 6H 5] (PPA) with a variety of ditopic pyrazoles Pz R1,R2H (where R 1 = R 2 = H for 1, R 1 = R 2 = Me for 2, R 1 = Ph, R 2 = Me for 3 and R 1 = R 2 = iPr for 4) produce salts 1– 4. Due to the presence of different substituents on pyrazole, each salt shows different structure. This study demonstrates
that the presence of different substituents on the pyrazole moieties provides sufficient non-covalent interactions which are
responsible for the different supramolecular structures adopted. Theoretical studies reveal that the proton affinity increases
on the nitrogen having lone pair of electron with the increase of electron density on pyrazole ring but the orientation remains
the same in both the solid and gaseous phase. 相似文献
15.
Starting from N-hydroxyphthalimide 1 and the reactive fluoro- or chloro-nitroaryl derivatives 2, 3 and 4a-e (2-chloro-3,5-dinitropyridine; 3, NBD-chloride; 4a, 1-fluoro-2,4-dinitrobenzene; 4b, picryl chloride; 4c, 4-chloro-3,5-dinitrobenzotrifluoride; 4d, 2-chloro-3,5- dinitrobenzotrifluoride; 4e, 4-chloro-3,5-dinitrobenzoic acid) the corresponding N-(2-nitroaryloxy)-phthalimide derivatives 5a-e, or 6 and 7 were obtained and characterized by IR, UV-Vis 1H-NMR and 13C-NMR spectroscopy. The TLC behavior and the hydrophobicity of these derivatives have been experimentally evaluated by R M0 parameters (using RP-TLC). The experimental R M0 parameters were compared with the calculated partition coefficient, log P. A QSPR study was also performed to establish possible
correlations between the structure and physical properties (λ max and R M0) of compounds 5a-e, 6, and 7.
相似文献
16.
One CO group of the dimethyldihydrophenanthrene mono-Cr(CO) 3 complex ( 1) was photochemically substituted for CS ( 2) or P(C 6H 5) 3 ( 3). Separation of all four possible stereoisomers [( R)
m
( R)
b
/( S)
m
( S)
b
and ( R)
m
( S)
b
/( S)
m
( R)
b
] of the complexes 1–3 was accomplished by two successive chromatographic steps: Separation of the enantiomers on triacetylcellulose was followed by MPLC at low temperatures to yield both epimers ( exo and endo). Their configurational assignment is based on optical comparison of the CD-spectra and on 1H-NMR-spectroscopy. The kinetics of the biphenyl flip were followed by CD and NMR. The results revealed that the rotational barriers around the biphenyl bond are hardly altered by the substitution of CO for CS or even P(C 6H 5) 3. Whereas exo and endo-isomers of 1 and 2 are obtained in appr. equal amounts, in the more crowded complex 3 the exo-isomer predominates over the endo-form by 80:20%.Dedicated to Prof. K. Komarek with cordial wishes on the occasion of the 60th anniversary of his birthday. 相似文献
17.
Three different H/D isotope effect in nine H 3XH(D) …YH 3 (X = C, Si, or Ge, and Y = B, Al, or Ga) hydrogen‐bonded (HB) systems are classified using MP2 level of multicomponent molecular orbital method, which can take account of the nuclear quantum nature of proton and deuteron. First, in the case of H 3CH(D) …YH 3 (Y = B, Al, or Ge) HB systems, the deuterium (D) substitution induces the usual H/D geometrical isotope effect such as the contraction of covalent R(C? H(D)) bonds and the elongation of intermolecular R(H(D) …Y) and R(C …Y) distances. Second, in the case of H 3XH(D) …YH 3 (X = Si or Ge, and Y = Al or Ge) HB systems, where H atom is negatively charged called as charge‐inverted hydrogen‐bonded (CIHB) systems, the D substitution leads to the contraction of intermolecular R(H(D) …Y) and R(X …Y) distances. Finally, in the case of H 3XH(D) …BH 3 (X = Si or Ge) HB systems, these intermolecular R(H(D) …Y) and R(X …Y) distances also contract with the D substitution, in which the origin of the contraction is not the same as that in CIHB systems. The H/D isotope effect on interaction energies and spatial distribution of nuclear wavefunctions are also analyzed. © 2015 Wiley Periodicals, Inc. 相似文献
18.
A molecular design strategy to develop receptor systems for the entrapment of noble gases, H 2 and N 2 is described using M06L‐D3/6‐311++G(d,p)//M06L/6‐311++G(d,p) DFT method. These receptors made with two‐, three‐, four‐ and five‐fluorinated benzene cores, linked with methelene units viz. R I, R II, R III and R IV as well as the corresponding non‐fluorinated hydrocarbons viz. R IH, R IIH, R IIIH and R IVH show a steady and significant increase in binding energy ( Eint) with increase in the number of aromatic rings in the receptor. A stabilizing “cage effect” is observed in the cyclophane type receptors R IV and R IVH which is 26–48% of total Eint for all except the larger sized Kr, Xe and N 2 complexes. Eint of R IV…He, R IV…Ne, R IV…Ar, R IV…Kr, R IV…H 2 and R IV…N 2 is 4.89, 7.03, 6.49, 6.19, 8.57 and 8.17 kcal/mol, respectively which is 5‐ to9‐fold higher than that of hexafluorobenzene. Similarly, compared to benzene, multiple fold increase in Eint is observed for R IVH receptors with noble gases, H 2 and N 2. Fluorination of the aromatic core has no significant impact on Eint (∼ ±0.5 kcal/mol) for most of the systems with a notable exception of the cage receptor R IV for N 2 where fluorination improves Eint by 1.61 kcal/mol. The Eint of the cage receptors may be projected as one of the highest interaction energy ranges reported for noble gases, H 2 and N 2 for a neutral carbon framework. Synthesis of such systems is promising in the study of molecules in confined environment. © 2018 Wiley Periodicals, Inc. 相似文献
19.
Summary The mechanism of the oxidation of mixtures of 2,6-dimethylaniline ( 1), N,N-dimethylaniline ( 2), 2,6-diethylaniline ( 3), N,N-diethylaniline ( 4), N-methylaniline ( 5), 2,6-difluoroaniline ( 6), and 2,3,5,6-tetrafluoroaniline ( 7) with 4-aminophenol ( 8) by cerium(IV) ions in aqueous perchloric acid has been investigated. The indoaniline salts [O=C 6H 4=N-C 6H 2( R
1) 2NH( R
2) 2] +ClO
4
–
( R
1=H, R
2=CH 3, C 2H 5 or vice versa) are formed as intermediates in the cross-coupling reaction; they undergo oxidation to imino-4-benzoquinone ( 9) and its corresponding derivatives by cerium(IV) ions in high yields. The mechanism of this process is discussed.
Durch Cer(IV)-Ionen induzierte oxidative Kreuzkupplung einiger 2,6- und N,N-disubstituierter Anilinderivate mit 4-Aminophenol in wässriger Perchlorsäure Zusammenfassung Die Oxidation von Mischungen von 2,6-Dimethylanilin (1), N,N-Dimethylanilin (2), 2,6-Diethylanilin (3), N,N-Diethylanilin (4), N-Methylanilin (5), 2,6-Difluoranolin (6) und 2,3,5,6-Tetrafluoranilin (7) mit 4-Aminophenol (8) durch Cer(IV)-Ionen in wässriger Perchlorsäure wurde untersucht. Als Zwischenprodukte der Kreuzkupplungsreaktion treten die Indoanilinsalze [O=C6H4=N-C6H2(R
1)2NH(R
2)2]+ClO
4
–
(R
1=H,R
2=CH3, C2H5 oder umgekehrt) auf. Diese werden durch Cer(IV)-Ionen in hohen Ausbeuten zu Imino-4-benzochinon (9) und seinen entsprechenden Derivaten oxidiert. Der Mechanismus dieses Vorgangs wird diskutiert. 相似文献
20.
Organosilicon gels [Co(NH 2R 2) 2Cl 2] and [Cr(NH 2R 2) 3Cl 3], containing a diaminodichloride complex of cobalt(II) and triaminotrichloride complex of chromium(III) (R 2 = CH 2CH 2CH 2SiO(OEt)), were synthesized by the hydrolysis of complexes [Co(NH 2R 1) 2Cl 2] ( I) and [Cr(NH 2R 1) 3Cl 3] ( II) incorporating peripheral triethoxysilyl groups (R 1 = CH 2CH 2CH 2Si(OEt) 3). The coprecipitated [Co(NH 2R 2) 2Cl 2] · 4NH 2R 3, [Cr(NH 2R 2) 3Cl 3] · 6NH 2R 3, [Co(NH 2R 2) 2Cl 2] · 2SiO 2, and [Cr(NH 2R 2) 3Cl 3] · xSiO 2 · (3 – x)SiHO 1.5 (R 3 = CH 2CH 2CH 2SiO 1.5) gels were obtained by cohydrolysis of complexes I and II with 3-aminopropyltriethoxysilane or triethoxysilane. Interaction with SiH(OEt) 3 is accompanied by the decomposition of silicon hydride groups and the formation of tetraethoxysilane derivatives. The heating of dry gels in a flow of argon or oxygen to 600° results in the formation of amorphous silica having a specific surface area 2–467 m 2/g and containing crystalline metals, their chlorides, oxides, silicates, or carbides. 相似文献
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