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1.
Reaction of the amines (CF3)2NX (X=Cl,Br) with norbornadiene either in solvent (CH2Cl2) at ?78 °C in the dark or in the vapour phase at 20 °C in daylight gives a mixture of 3-halogeno-5-(NN-bistrifluoromethylamino)nortricyclene (exo, endo-and exo, exo-isomers) and exo-5-(NN-bistrifluoromethylamino)- anti-7-halogenonorbornene in quantitative yield formed via halonium ion addition to the diene. The reaction of the amine (CF3)2NBr in solvent Me2O or Et2O at ?78 °C in the dark gives the same products in low yield, together with 3-bromo-5-alkoxynortricyclene (exo, endo- and exo, exo-isomers) and the amine (CF3)2NR (R=Me, Et) in high yield.  相似文献   

2.
The lithium polyfluorobenzenesulphinates, Li O2SR (R = C6F5, p-HC6F4, m-HC6F4, or o-HC6F4), and the dilithium tetrafluorobenzenedisulphinates, p- and o-(LiO2S)2C6F4, have been prepared by reaction of the appropriate polyfluoroaryllithium compounds with sulphur dioxide. All compounds were isolated as hydrates and gave the corresponding S-benzylthiouronium salts on treatment with S-benzylthiouronium chloride. From reactions of the lithium sulphinates with suitable mercuric salts in water, generally at room temperature, the derivatives RHgX (R = C6F5, X = Cl, Br, CH3CO2, or PhSO2; R = p-HC6F4, X = Cl, Br, or CH3CO2; R = m-HC6F4, X = Cl or Br; R = o-HC6F4, X = Cl), p-(XHg)2C6F4 (X = Cl, Br, or CH3CO2), and o-(XHg)2C6X4 (X = Cl or Br) have been prepared. Similarly, the bispolyfluorophenylmercurials R2Hg (R = C6F5, p-HC6F4, or m-HC6F4) have been prepared from the corresponding lithium sulphinates and either mercuric salts or polyfluorophenylmercuric halides in aqueous t-butanol. A possible mechanism for the sulphur dioxide elimination reactions is discussed.  相似文献   

3.
A sequence of formylation followed by a carbene insertion reaction has led to the stepwise introduction of additional ethano bridges into 4,5,7,8- tetramethyl [22](1,4)cyclophane (1), providing syntheses of 5,7,8-trimethyl- [23](l,2,4)cyclophane (6), a mixture of 5,8-dimethyl[24(1,2,4,5)cyclophane (10) and 5,7-dimethyl[24(1,2,3,5)cyclophane (11, and-4-methyl[25](1,2,3,4,5)-cyclophane (14). This route to 14 completes a formal eight-step synthesis of [26](1,2,3,4,5,6)cyclophane (15, superphane) with an overall yield of 17%. A Birch reduction of 6 readily gave 12,15-dihydro-5,7,8-trimethyl[23](1,2,4)-cyclophane (7) in 85% yield.  相似文献   

4.
Reactions of urotropine (C6H12N4) with trimethylmetal derivatives of Al, Ga, In und Tl in various (1114) molar ratios lead to stable and monomeric 11, 12 or 13 adducts in good yields, but no 14 addition product could be isolated. The vibrational spectra (IR and Raman) of all compounds are recorded and partly assigned. Some characteristic frequencies of the C6N4-skeletons clearly show the symmetry changes in the series of the 111213 adducts (CC → C). The X-ray structure determinations of C6H12N4·.GaMe3 (MeCH3) and C6H12N4·.2GaMe3, are in good agreement with the vibrational spectra. Both compounds crystallize in monoclinic space groups (P21 and C2/c). The GaN distances are around 214 pm, and the values for the C6N4-skeletons are not significantly different from those for free urotropine.  相似文献   

5.
Oxidation of benzotropylium (1) fluoborate with Na2O2 and KO2 gives the benzotropones, 5 and 6, as the major products with no naphthalene (9) or other ring contracted products formed. Oxidation with m-chloroperoxybenzoic acid produces a small amount of naphthaldehydes (10 and 11) and even less naphthalene, a long with the benzotropones, while oxidation with H2O2 and t-butyl peroxyacetate gives slightly more of the ring contracted naphthaldehydes than benzotropones, in addition to a small quantity of naphthalene. All reactions produce some 1,2-benzotropilidene (8)  相似文献   

6.
Synthesis and properties of C5H5(CO)2Mn-N2H4-Cr(CC)5(1), C5H5(CO)2Mn-N2H2-Cr(CO)5(2) and C5H5(CO)2Mn-N2-Cr(CO)5(3) are reported. (1), (2) and (3) constitute the first series of heteronuclear complexes in which N2, N2H2 and N2H4 are bound to identical metal centers. (1) and (3) are obtained by reacting C5H5Mn(CO)2N2H4 respectively with Cr(CO)5THF, (2) by oxidation of (1). (2) disproportionates by addition of base yielding (3) and H2. The IR Spectrum of (2) allows the assignment of five normal vibrations of the diazene ligand; in the IR spectrum of the deuterated analogue all six normal vibrations can be assigned. The 1H-NMR spectrum of (2) yields the coupling constant of protons on NN double bonds for the first time; the value of 3JHH  23,5 Hz points to a trans structure of (2).  相似文献   

7.
The β-chlorovinylphosphines R2PC  CCl(CF2)3 (R = C6H5, C6H11) react with Fe(CO)5 yielding compounds of stoichiometry
. The crystal structure of one of these (R = C6H11) has been determined from X-ray diffraction data and refined by least-squares to R = 0.037 (2313 reflections with I > 2.3σI). Crystals are triclinic, space group P1, a = 10.253(5), b = 15.590(7), c = 9.390(4)Å, α = 99.88(3), β = 103.21(2), γ = 92.02(2)°, Z = 2. The fluorinated π-allyl group is σ-bonded to one Fe atom and π-bonded to the other.  相似文献   

8.
Optical absorption and emission spectra are reported for single crystals of the cubic elpasolite Cs2NaSmCl6. The variable temperature spectra obtained at high resolution are assigned using energies and relative intensities. Transitions from the ground level, 6H52 to cystal fi levels of 6H72-152, 6F12-112, 4G52-92, 4F32,52, 4I92, and 6P32, 52 are located and characterized. Intensity calculations are reported for magnetic dipole allowed transitions. The dominance of vibronic intensity in 6H526F 12-92 and 6P32, 52 transitions is accounted for qualitatively through the ligand polarization model involving quadrupole metal (Sm3+)-ligand (Cl?) interaction mechanisms. The Eu″(6H52)→E′(6H12) Eu′(6F12) no-phonon transition is postulated to be pure electric quadrupole allowed. The ground state magnetic moment is determined to be very small from magnetic circular dichroism (MCD) spectra.This study has led to the assignment of nearly all of the crystal field levels in the visible and IR region for Cs2NaSmCl6. A total of 27 such levels were identified, 17 from no-phonon transitions and the rest from vibronic transitions. The magnetic dipole intensity calculated using intermediate coupling Oh wavefunctions along with a crystal field analysis of the splitting pattern was used in the assignment of the levels. Vibronic bands were observed for all transitions and their vibrational symmetries were tentatively assigned. MCD data were used to determine the magnet moment of the ground state.  相似文献   

9.
The diene 1a reacted with CHCl3/aq. NaOH/PTC in CH2 Cl2 unexpectedly to give a mixture of the chlorination products 2 and 3a. Usual chlorination with Cl2 yielded similarly 2, 3a, and 3b dependent on the amount of Cl2. The formation of 2 as well as the reaction of 7 to give 9 (besides 8) shows an unusual Cl-Cl-interaction.  相似文献   

10.
Acid-catalysed ring opening of the spirodienones (2a) and (2b) using p-toluene-sulphonic acid affords the styrène derivatives (3a) and (3b), while treatment with acetic anhydride/H2SO4 affords the furan derivatives (4a) and (4b).  相似文献   

11.
Two cyclohumulanoids, dl-bicyclohumulenone (4) and dl-africanol (7 were synthesized through newly developed conformationally selective transannular cyclization of humulene 9,10-epoxide (2). The epoxide 2 was converted to a bicyclohumulenediol diacetate 3a in 70% yield by treatment with BF3·OEt2-Ac2O, while treatment of 2 with trimethylsilyl trifluoromethansulfonate gave an africen-10-ol (5a and 5b) in 80% yield. The two intermediates 3a and 5a furnished the natural products 4 and 7 in 30 and 8 % yield from 2 respectively.  相似文献   

12.
Adenosine cyclic 3′,5′-phosphoramidate 2 was synthesized by reacting adenosine cyclic 3′,5′-phosphate 1 with POCl3, in trimethyl phosphate for 1 h at O°C, followed by in situ treatment of the reaction mixture with a suspension of (NH4)2CO3 in anhydrous DMF or pyridine or DMF/pyridine mixture for 30 min at 25° C. Diastereoisomers (RP)-2 and (SP)-2 the relative quantities of which depended on the solvent of (NH4)2CO3 treatment, were separated by reversed phase partition chromatography. Hydrolysis of (RP)-2 and (SP)-2 proceeded with predominant (90% in 0.1 N HCl, 100% in 0.1 N NaOH) -P-O-C bond breaking.  相似文献   

13.
Reductive coupling of methyl-vinyl ketone with TiCl4-Mg gives pinacol 1 (25%). According to the reducing agents, mesityl oxide yields 2,4,5,7-tetramethyl-octa-2,4,6-triene 3 (with 4TiCl3-LialH4), triene 3 or 2,4,5,7-tetramethyl-octa-2,6-dien-4,5-diol 5 (with TiCl4-Mg), pinacol 5 (with VCl3-Mg), and 2-acetyl-1,3,3,4,4-pentamethyl-cyclopentane 7 (with CrCl3-Mg or FeCl3-Mg or ZrCl4 or ZrCl4-Mg) as major products.  相似文献   

14.
A new C3-unit substitution reaction at C-4 position of 4- acetoxyazetidinone derivative (1 and 5) by tetraallyltin (2) in the presence of 1/10 eq. of BF3-ether in methylene chloride is described. From 4-allylazetidinone derivative (3) via ylid intermediate (14) dethiathienamycin (16) was synthesized.  相似文献   

15.
The structure of [Pt2Cl(CO) (μ-Ph2PCH2PPh2)2] [PF6] was determined by X-ray methods and refined to R = 0.082, using diffractometric intensities of 5646 independent reflections. The crystals are monoclinic, space group P21/n, a = 12.919(3), b = 15.576(6), c = 25.151(5)Å, β = 94.82(3)°, Z = 4. They are built of octahedral hexafluorophosphate anions and dinuclear platinum(I) cations. The latter contain PtCl and PtCO fragments linked to one another by a PtPt σ-bond and by two bridging bis(diphenylphosphino)methane ligands. The platinum atoms are in square planar environments and the dihedral angle between the two coordination planes is 40.1°. Selected bond lengths are: PtPt 2.620(1), PtCl 2.384(5), PtC 1.89(3) and PtP 2.291(5) – 2.308(5)Å.  相似文献   

16.
The vapour phase reaction of ammonia and hexafluoroacetylacetone leads to the formation of the new β-keto-amine C5H3F6NO. Crystals of the compound are monoclinic, space group P21/n, a = 10.01(2), b = 19.33(3), c = 8.40(1) Å, β = 82.27(6)°; final R = 0.044.  相似文献   

17.
The synthesis and mechanism of formation of phosphonium salts of the type [R3P+CFXY]Z? (where X = F, Cl, Br; Y = Br, Cl; Z = Br, Cl), bis-phosphonium salts of the type [R3P+CF2P+R3]2Br?, and phosphoranium salts of the type [R3P+C?FP+R3]X? (X = Br, Cl) will be presented. The applicability of these substrates in the generation of useful nucleophilic or electrophilic synthetic intermediates will be discussed.  相似文献   

18.
Previous (1) work on ternary chalcopyrite solid solution formation has shown that the difference in end point axial ratios (Δca) is an important factor in determining the extent of mutual solubility. It was concluded that when Δca > 0.13 complete solid solubility will not occur. In this work it is shown that complete solid solution formation in the systems AgAlS2AgInS2 (Δca = 0.111), AgGaS2AgInS2 (Δca = 0.11) and AgAlSe2AgInSe2 (Δca = 0.112) does occur. This shows that the value of Δca = 0.13 as an upper limit for solid solution formation can be approached closely.  相似文献   

19.
The nitrosoarenes ArNO (Ar = C6H5, 2-MeC6H4, 2,4,6- Me3C6H2 and C6F5) have been condensed with 4-(dichloroamino)- tetrafluoropyridine to provide the azoxy-compounds pyFNN+(N-)Ar (pyF = 2,3,5,6-tetrafluoro-4-pyridyl); de-oxygenation of the first three with triphenylphosphine or triethyl phosphite gave the corresponding azo-compounds, and the reverse reaction was achieved in the case of pyFNNC6H2Me3-2,4,6 using peroxytrifluoroacetic acid. Thermolysis of 4-azidotetrafluoropyridine in the presence of pentafluoronitrosobenzene provided the perfluorinated azoxy-compound pyFNN+(O-)C6F5. X-Ray methods have been used to determine the molecular geometry of pyFNN+(O-)C6H2Me3-2,4,6.  相似文献   

20.
Fluorination of triphenylarsine oxide by aqueous hydrogen fluoride (1–40%) in the absence of glass readily gives triphenylarsine difluoride. When the reaction with dilute (1%) aqueous hydrogen fluoride is carried out in borosilicate glass apparatus, the glass participates in the reaction resulting in the formation of the crystalline 2:1 adduct 2Ph3AsO·HBF4. Crystals of this compound are monoclinic, P21/c, a = 12.926(4), b = 17.819(6), c = 14.994(4) Å, β = 98.97(3)°, Z = 4. The structure contains cations [(Ph3AsO)2H]+ in which O?O is 2.44(2)Å, and anions BF4?.  相似文献   

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