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1.
Kota Sato Tatsuo Goto Susumu Iwabuchi Hidefumi Hirai 《Journal of polymer science. Part A, Polymer chemistry》1993,31(3):763-768
The geometrical and electronic structures of the binary radical complexes of 2-methoxycarbonyl propyl radical with boron trichloride and with boron trifluoride were determined by using an ab initio molecular orbital method. The 2-methoxycarbonyl propyl radical complex was a model of the growing radical end in the copolymerization of methyl methacrylate in the presence of boron halides. The most stable structure of the binary radical complex composed of 2-methoxycarbonyl propyl radical with boron trichloride was a twisted form in which the dihedral angle between the vinyl group and the ester group was 32°, while that of the binary radical complex composed of methyl methacrylate radical with boron trifluoride was a planar form as the free radical. The frontier orbital energy of 2-methoxycarbonyl propyl radical was lowered by 0.06 au by the coordination of boron trichloride, while that was lowered only by 0.02 au by the coordination of boron trifluoride. The polymerization mechanism was elucidated on the basis of these predictions. © 1993 John Wiley & Sons, Inc. 相似文献
2.
An efficient and simple method for the synthesis of 2-unsubstituted 1-aryl-4- and 1-aryl-5-acylimidazoles has been developed. It consists in the condensation of α-diketone monooximes with aromatic amines and formaldehyde on the presence of boron trifluoride etherate, leading to the formation of stable boron trifluoride complexes of N-oxides. Further reduction of these complexes led to the corresponding imidazoles. This method permits broad variations of substituents in the aryl part of these compounds. 相似文献
3.
Various complexes (RnMO·BF3) of boron trifluoride with sulphoxides, aminoxides, phosphinoxides and arsinoxides have been prepared and investigated using proton, fluorine (at variable temperature) boron and phosphorus resonance. A comparison with similar adducts containing a co-ordinative O? B bond is presented. 相似文献
4.
Kota Sato Yoshiro Sakuma Susumu Iwabuchi Hidefumi Hirai 《Journal of polymer science. Part A, Polymer chemistry》1992,30(9):2011-2015
The stereo- and electronic structures of the binary molecular complex composed of methyl methacrylate and boron trifluoride are obtained by using an ab initio molecular orbital method with an STO-3G basis set. The total energy change on the binary molecular complex formation is ?1.3 X 10?2 Hartree (?8.2 kcal/mol). The electron transfer from methyl methacrylate to boron trifluoride and the change in the energy level of the lowest unoccupied molecular orbital of methyl methacrylate on the complex formation with boron trifluoride are much smaller than those on the complex formation with boron trichloride. A twisted form in which the dihedral angle between the vinyl plane and the ester plane is 16.9° is the most stable structure of the binary molecular complex composed of methyl methacrylate and boron trifluoride. A strong bonding overlap population between a β-hydrogen of methyl methacrylate and a fluorine of boron trifluoride is found in this conformation. © 1992 John Wiley & Sons, Inc. 相似文献
5.
Thomas A. Ford 《International journal of quantum chemistry》2012,112(2):478-488
The structure, the interaction energy, and the vibrational spectrum of the electron donor–acceptor complex formed between boron trifluoride, as a Lewis acid, and formaldehyde, as a Lewis base, have been determined by means of ab initio calculations at the second‐order level of Møller–Plesset perturbation theory, using a triple‐zeta basis set with polarization and diffuse functions on all atoms. The object was to examine the differences in the properties of the complexes formed between boron trifluoride and an oxygen base containing oxygen in the sp2 hybrid state with those of some sp3 oxygen bases studied earlier. The investigation has then been extended to include the related bases thioformaldehyde and methanimine, to assess the effect of substituting the oxygen atom by a sulphur atom or an imino group. A further range of formaldehyde analogs, containing one and two methyl groups, one and two fluorine atoms, and one methyl group and one fluorine atom, has also been included. The preferred structure of each complex has been identified. The computed data have been compared, and the complex properties correlated with some relevant physical properties of the bases. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
6.
Ahmet Kilic Cezmi Kayan Murat Aydemir Feyyaz Durap Mustaf Durgun Akn Baysal Esref Tas Bahattin Gümgüm 《应用有机金属化学》2011,25(5):390-394
Two new boron complexes were synthesized from N‐[3‐(methylmercapto)aniline]‐3,5‐di‐tert‐butylsalicylaldimine ( LH ) with boron reagent BPh3 or BF3.Et2O. These boron complexes are stable and easily soluble in protic solvents such as ethanol (C2H5OH) but hardly soluble in nonprotic solvents such as chloroform (CHCl3), dichloromethane (CH2Cl2) and tetrahydrofuran (THF). All new boron complexes have been fully characterized by both analytical and spectroscopic methods. The catalytic activities of complexes [LBPh2], 2 , and [LBF2], 3 , in the transfer hydrogenation of acetophenone derivatives were tested. Stable boron complexes were found to be efficient catalysts in the transfer hydrogenation of aromatic ketones in good conversions up to 99% in the presence of iso‐PrOH/KOH. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
7.
8.
Hidefumi Hirai Tadashi Ikegami 《Journal of polymer science. Part A, Polymer chemistry》1970,8(9):2407-2419
The polymerization of the complex of methyl methacrylate with stannic chloride, aluminum trichloride, or boron trifluoride was carried out in toluene solution at several temperatures in the range of 60° to ?78°C by initiation of α,α′-azobisisobutyronicrile or by irradiation with ultraviolet rays. The tacticities of the resulting polymers were determined by NMR spectroscopy. Both the 1:1 and the 2:1 methyl methacrylate–SnCl4 complexes gave polymers with similar tacticities at the polymerization temperatures above ?60°C. With decreasing temperature below ?60°C, the isotacticity was more favored for the 2:1 complex, whereas the tacticities did not change for the 1:1 complex. On the ESR spectroscopy of the polymerization solution under the irradiation of ultraviolet rays at ?120°C, the 1:1 SnCl4 complex gave a quintet, while the 2:1 SnCl4 complex gave both a quintet and a sextet. The sextet became weaker with increasing temperature and disappeared at ?60°C. This behavior of the sextet corresponds to the change of the tacticities of polymer for the 2:1 SnCl4 complex. An intra–intercomplex addition was suggested for the polymerization of the 2:1 complex, which took a cis-configuration on the basis of its infrared spectra. The sextet can be ascribed to the radical formed by the intracomplex addition reaction, while the quintet can correspond to that formed by the intercomplex addition reaction. The proportion of the intracomplex reaction was estimated to be about 0.25 at ?75°C, and the calculated value of the probability of isotactic diad addition of the intracomplex reaction was found to be almost unity. 相似文献
9.
Halit Kantekin Ümmühan Ocak Yaşar Gök 《Journal of inclusion phenomena and macrocyclic chemistry》2002,43(3-4):175-178
A new (E, E)-dioxime cobalt(III) complex [Co(HL)2pyCl]containing four 23-membered macrocyclic ionophores has beenprepared. The cobalt(III) complex [Co(LBF2)2pyCl]bridged with BF2
+ was prepared using the precursorcobalt(III) complex and boron trifluoride ethyl ethercomplex. The solvent extraction of heavy metal cationssuch as Ni2+, Cu2+, Zn2+, Hg2+ and Pb2+ by the BF2
+-capped cobalt(III) complex has been investigated. The structure of the complexes is proposedaccording to elemental analyses, 1H and 13C-NMR, IRand mass spectral data. 相似文献
10.
Structure and Reactivity of Uracil Derivatives. 2. Ambident Nucleophilic Reactivity of 5-Diazouracil
On the basis of 3-21G type ab initio calculations we have studied all the possible complexes of 5-diazouracil with boron trifluoride. The most stable of these are the systems with the BF3 coordinated at the 3, 9, and 10 positions of the heterocyclic molecule. 相似文献
11.
Alexander O. Terent'evAlexander V. Kutkin Maxim M. PlatonovYuri N. Ogibin Gennady I. Nikishin 《Tetrahedron letters》2003,44(39):7359-7363
A reaction of cycloalkanone, alkanone and alkyl aryl ketone ketals with H2O2 catalyzed by boron trifluoride etherate and boron trifluoride-methanol complexes was studied. A new versatile method for the synthesis of bishydroperoxides and their derivatives, viz. 1,1′-dihydroperoxyperoxides and 1,2,4,5-tetraoxacyclohexanes, was developed based on this reaction. 相似文献
12.
M. V. Lebedev V. G. Nenaidenko K. I. Smolko E. S. Balenkova 《Russian Journal of Organic Chemistry》2001,37(3):326-333
Cyclopropyl-substituted alkenes react with complexes formed by boron trifluoride and 3-(ethylthio)propionyl fluoride and 2-(ethylthio)acetyl fluoride to give ketones containing an ethylthio group. In most cases the reaction is not accompanied by opening of the three-membered ring or rearrangements. 相似文献
13.
Lucien Elegant Marcel Azzaro Raymonde Makowski-Favelier Grard Mavel Nicole Morize 《Magnetic resonance in chemistry : MRC》1969,1(6):471-479
Various complexes of boron trifluoride and typical organo-phosphours compounds have been investigated using proton and fluorine resonance (at variable temperature) and boron and phosphorus resonance. In BF3, boron resonance is insensitive to the complex strength, but fluorine resonance suggests the possibility of various types of complexes on the phosphorus group or, additionally on the heteroatoms (e.g. oxygen, nitrogen) of the molecule. These complexes are probably σ type. Proton chemical shifts in the organo-phosphorus compounds follow the same trends as in similar complexes of amines, esters etc.; these perturbations may be mainly due to magnetic anisotropy effects; proton-phosphorus couplings conversely follow changes in phosphorus electronegativity. 相似文献
14.
A series of unsymmetrical difluoro‐boron(BF2) complexes with pyridine and imidazoline were synthesized by reaction of new chelating ligands (arylmethyl‐imidazolidinylidene)‐pyridin‐2‐yl‐amine with boron trifluoride diethyl etherate. All the ligands and BF2 complexes were structurally characterized by IR, HRMS, 1H, 13C,11B, and 19F NMR, indicating the bidentate complexation of imidazoline nitrogen and the pyridine nitrogen to the boron center. Evaluation of agricultural bioactivities showed that some of the BF2 complexes exhibited moderate fungicidal activities, and most of the BF2 complexes exhibited higher activities than the none‐BF2 complexed substrates. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 20:418–424, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20567 相似文献
15.
The regioselectivity of the complexation of chromenes with tricarbonyl(trispyridine)chromium [Cr(CO)3Py3] can be controlled by the addition of BF3·Et2O boron trifluoride etherate. Depending on the molar ratio of the Lewis acid, different complexes can be prepared. The spectrokinetic properties of the so‐formed complexes were studied and it was shown that the thermal bleaching constants are either more or less reduced, depending on the position of the chromium tricarbonyl moiety. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
16.
Masao Kato Hiroyoshi Kamogawa 《Journal of polymer science. Part A, Polymer chemistry》1968,6(11):2993-3006
Solution polymerizations of allyl(o-vinyl phenyl)ether and allyl(p-vinyl phenyl)ether with cationic and radical initiators were investigated. Soluble polymers were formed in polymerizations with boron trifluoride etherate and with benzoyl peroxide. In polymerization with azobisisobutyronitrile the polymerization in dilute solution gave a soluble polymer, whereas that in concentrated solution gave a crosslinked, insoluble one. For informationon the polymerization behavior some infrared and ultraviolet spectroscopic investigations of the soluble polymers were made. From these results it appears that polymers with pendant allyl groups are formed in polymerization with boron trifluoride etherate at low temperature, and polymers containing pendant vinyl groups and allyl groups are obtained with the two types of radical initiator. Copolymerizations of these monomers with ethyl vinyl ether and styrene with the use of boron trifluoride etherate were sucessfully effected. Such reactions as Claisen rearrangement, crosslinking induced with radical initiators, and epoxidation with perbenzoic acid were examined for the polymers prepared in the polymerization with boron trifluoride etherate. Good results were obtained for the former two reactions. However, the latter was unsuccessful. 相似文献
17.
Yu. Yu. Titova L. B. Belykh A. V. Rokhin O. G. Soroka F. K. Schmidt 《Kinetics and Catalysis》2014,55(1):35-46
The catalytic characteristics of the individual complex Ni(PPh3)2(C2H4) and Ni(PPh3) n Cl (n = 2 or 3) and those of systems based on these complexes in combination with Brönsted and Lewis acids in ethylene and propylene oligomerization have been determined. A correlation between the BF3 · OEt2 solution storage time and the catalytic properties of the nickel systems has been established for the reactions of the lower alkenes. The observed increase in the turnover frequency and turnover number of the catalyst is due to the increase in the Brörsted acid concentration as a result of irreversible conversions of BF3 · OEt2 caused by its interaction with impurity water in the solvent. The formation of the Ni(PPh3)2(C2H4)-BF3 · OEt2 catalytic system in the presence of a substrate dramatically extends the system’s service life. The interaction of the nickel precursors with boron trifluoride etherate has been investigated using a complex of physical methods, and the main reactions yielding catalytically active species have been revealed. 相似文献
18.
Rumyantsev E. V. Desoki A. Marfin Yu. S. Antina E. V. 《Russian Journal of General Chemistry》2010,80(9):1871-1875
Intermediate products of synthesis of the boron trifluoride complexes with linear oligopyrroles are found. By means of electronic
spectroscopy it was shown that the reaction of linear oligopyrroles with boron trifluoride in solutions resulted in the formation
of stable donor-acceptor complexes. Their composition was established and the formation constants were evaluated. It was shown
that transformation of these complexes in the corresponding borofluoride complexes is possible only while boiling the reaction
mixture. By means of quantum-chemical methods the structural and energy parameters of the donor-acceptor complexes under study
were calculated. 相似文献
19.
Nonfluorescent 4,4′,5,5′-tetramethyl- and 4,5,4′,5′-bistetramethylene biimidazol-2-yls 5 and 6 combined with boron trifluoride to give the tetramethyl and bistetramethylenebiimidazol-2-yl–BF2 complexes 9 and 10 isolated as strongly fluorescent BF3 salts, λf (dichloromethane): 377 nm Φ 0.93 and 386 nm Φ 0.90. Similarly, fluorescent bibenzimidazol-2-yl 7 , λf (ethanol), 370 nm Φ 0.14, gave a BF2 complex 11 isolated as a BF3 salt λf (ethanol), 417 nm Φ 0.68. 相似文献
20.
O. N. Bubel' V. A. Konovalov I. G. Tishchenko 《Chemistry of Heterocyclic Compounds》1987,23(8):836-838
The reaction of boron trifluoride etherate with cis- and trans-2-aryl-3-aroylaziridines yields the respective complexes in high yield. According to PMR spectral data the methyl group of boron trifluoride trans-1-methyl-3-aroylaziridines is located in syn-position, and in the cis-aziridine complexes in anti-position, to the carbonyl group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1047–1049, August, 1987. 相似文献