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Sulfinyl fluoride and N-(F-isoprophyl)iminosulfur difluoride form the compounds, OSN(CH3)CH2CH2N(CH3) and i-C3F7NSN(CH3CH2CH2N(CH3 with symdimethylethylenediamine (1). In contrast, CF3C(O)NSF2 and (Rf)2SF2 (Rf = CF3, i-C3F7 form only acyclic compounds, CF3C(O)N(CH3)CH2CH2N(CH3)C(O)CF3 and RfSN(CH3)CH2CH2N(CH3)SRf with (1). With PF3, PF5 and OPF3, cyclic compounds N(CH3)CH2CH2N(CH3)PF, N(CH3)CH2CH2N(CH3)PF3, and N(CH3)CH2CH2N(CH3)P-(O)F result. When the latter two compounds are reacted further with LiNC(CF3)2, N(CH3)CH2CH2N(CH3)PF2NC(CF3)2 and N(CH3CH2CH2N(CH3)P(O)NC(CF3)2) form.  相似文献   

5.
For the 53 neutral atoms from He to Xe in their ground states, the average distances < u> n l , n l in position space and < v> n l , n l in momentum space between an electron in a subshell nl and another electron in a subshell n l are studied, where n and l are the principal and azimuthal quantum numbers of an atomic subshell, respectively. Analysis of 1700 subshell pairs shows that the electron-pair distances < u> n l , n l in position space have an empirical but very accurate linear correlation with a one-electron quantity U n l , n l L r +S r 2/(3L r ), where L r and S r are the larger and smaller of subshell radii < r> n l and < r> n l , respectively. The correlation coefficients are never smaller than 0.999 for the 66 different combinations of two subshells appearing in the 53 atoms. The same is also true in momentum space, and the electron-pair momentum distances < > n l , n l have an accurate linear correlation with a one-electron momentum quantity V n l , n l L p +S p 2/(3L p ), where L p and S p are the larger and smaller of average subshell momenta < p> n l and < p> n l , respectively. Trends in the proportionality constants between < u> n l , n l and U n l , n l and between < > n l , n l and V n l , n l are discussed based on a hydrogenic model for the subshell radial functions. Received: 8 April 1998 / Accepted: 6 July 1998 / Published online: 18 September 1998  相似文献   

6.
The compounds Ba4Fe2S6[S23(S2)13] and Ba3.6Al0.4Fe2S6[S0.6(S2)0.4], designated I and II, were prepared by reacting BaS, Fe, and S powders and Al foils in graphite containers sealed in evacuated quartz ampoules at approximately 1100°C. The crystal structure of I was determined using 1682 independent, nonzero X-ray reflections, while 3589 were used for II. They are triclinic, Al:
a=9.002(2)A?,b=6.7086(8)A?,c=24.658(4)A?α91.49(2)°,
β=105.10(2)°y=90.74(2)°,ψcalc=4.15g/cm3,for I:
a=8.993(6)A?,b=6.708(7)A?,c=24.70(1)A?α91.11(6)°,
β=105.04(6)°y=90.90(9)°,ψcalc=3.90g/cm3,for II:
BaS6 trigonal prisms share edges to form distorted hexagonal rings which form one-dimensional chains leaving two free lateral edges. The chains link in a stairstep manner with the rings offset along the [301] direction. These stairsteps join in a complicated manner to form a three-dimensional network. Fe ions are in two sites forming isolated FeS4 tetrahedra and isolated Fe2S6 dimers by edge-sharing tetrahedra. The Al substitution occurs in the trigonal prisms which have free edges with Al replacing Ba. Room-temperature Mössbauer isomer shifts are 0.20 mm/sec. for I and 0.30 mm/sec for II. These data indicate that upon Al substitution charge compensation occurs by reducing Fe3+. Valence calculations indicate that Fe in edge-sharing tetrahedra are reduced while the Fe in the isolated tetrahedron remains unchanged. The effective charge distribution in the Al substituted compound is approximately Fe3+, Fe2.5+ with electron delocalization across the shared edge. Room temperature electrical resistivity is 105 ohm/cm. The compositions of the crystals are best represented by the formulas [Ba4Fe2S7]23·[Ba4Fe2S6(S2)]13 and [Ba3AlFe2S7]0.4·[Ba4Fe2S7]0.2·[Ba4Fe2S6(S2)]0.4. The replacement of a sulfide by a disulfide ion is thought to be strongly dependent on the sulfur activity during the preparation.  相似文献   

7.
The synthesis of 3-acetylcyclohexanones 11, 12, 13 has been realized by conjugate addition of lithiated cyanohydrin ether 1a to 2-cyclohexenones 2, 3, 4 in THF-HMPA, even if 3-substituted. 3-benzoylcyclohexanones 14, 15, 16 are obtained from 1b and 2, 3, 4 in THF with excellent yields.  相似文献   

8.
The reactions of n-butyl stannonic acid with(PhO) 2 P(O)H leads to the formation of a hexameric tin cage [{(n-BuSn) 3 (PhO) 3 O} 2 {HPO 3 } 4 ].This reaction involves an in situ P─O bond cleavage and the generation of a [HPO 3 ] 2? ion. A direct reaction of six equivalents of n-BuSnO(OH) acid with six equivalents of C 6 H 5 OH and four equivalents of H 3 PO 3 also leads to the formation of same cage structure. A tetranuclear organooxotin cage[(PhCH 2 ) 2 Sn 2 O(O 2 P(OH)-t-Bu) 4 ] 2 has been assembled by debenzylation involving the reaction of (PhCH 2 ) 2 SnCl 2 ,(PhCH 2 ) 2 SnO·H 2 O or (PhCH 2 ) 3 SnCl with two equivalents of t-BuP(O)OH 2 . A half-cage intermediate [(PhCH 2 ) 2 Sn 2 O(O 2 P(OH)-t-Bu) 4 ] has been detected. New organotin cations of the type [n-Bu 2 Sn(H 2 O) 4 ] 2+[2,5-Me 2 -C 6 H 3 SO 3 ]? 2 and {[n-Bu 2 Sn(H 2 O) 3 LSn(H 2 O) 3 (n-Bu) 2 ] 2+[1,5-(SO 3 ) 2 -C 10 H 6 ] 2?} have been obtained in the reactions of n-Bu 2 SnO or (n-Bu 3 Sn) 3 O with 2,5-dimethyl sulfonic acid and 1,5-naphthalene disulfonic acid respectively. These organotin cations form interesting supramolecular structures in the solid state as a result of O─H─···O hydrogen bonding.  相似文献   

9.
The Flory-Williams rotational isomeric state models describing the conformational characteristics of polyesters and polyamides are combined to calculate the dimensions of the alternating polyesteramide (PEA) of the type 6NT6. The calculated ratio of unperturbed dimensions (〈r2o/M)12 is 1.03 A?/gmole12 in excellent agreement with the value 1.00 A?/gmole12 recently obtained from an intrinsic viscosity-molecular weight study of PEA.  相似文献   

10.
The solubility parameter of poly(hexamethylene oxide) has been estimated by measuring solution viscosities and by turbidimetric titrations in a series of solvents. From both experimental methods, a value of δp = 33.9 J12cm?32 (8.1 cal12cm?32) was obtained, whence the cohesive energy density is 274.5 J cm?3 (65.6 cal cm?3). These experimental values are compared with those calculated by empirical methods.  相似文献   

11.
Unstable transition metal compounds formed from hydridosilacyclobutanes are described: 1-methyl-1-silacyclobutane reacts with nonacarbonyldiiron to give the complexes [Fe(CO)4(H){Si(Me)CH2CH2CH2}] and [Fe{CH2CH2CH2Si(H)Me}(CO)4], and with bis(triphenylphosphine)(ethylene)platinum(0) to give [Pt(H)(PPh3)2{Si(Me)CH2CH2CH2}].  相似文献   

12.
The rz structure of 1,1-dichloroethylene has been determined by a joint analysis of the electron diffraction intensity and the rotational constants as follows: rz(CH) = 1.088 ± 0.011, rz(CC) = 1.329 ± 0.003, rz(CCl) = 1.725 ± 0.002 A?, ∠zHCH = 121.4 ± 0.7 andzClCCl = 114.1 ± 0.2°. The uncertainties represent estimated limits of error. The observed structural parameters are compared with those for related compounds and the systematic trends in the bond lengths and bond angles are discussed. The effective constants representing anharmonicity have been obtained from an analysis of the isotopic differences in the rz structure. By using the rz parameters and the effective constants, the equilibrium structure has been estimated as follows: re(CH) = 1.079 ± 0.012, re(CC) = 1.324 ± 0.005, re(CCl) = 1.721 ± 0.003 A?, ∠eHCH = 120.5 ± 0.8 andeClCCl = 114.0 ± 0.3°.  相似文献   

13.
The preparation of the first mixed metal cyclometallated compounds [ClPd(p-RC6H3CHNNCH(p-RC6H3))PtCl]n (R = H, Cl) are reported; they were made from monocyclopalladated [(AcO)Pd(p-RC6H3CHNNCH(p-RC6H4)]2 and PtCl42?.  相似文献   

14.
The mono(pentamethylcyclopentadienyl) lanthanide complexes [(C5Me5)Yb(μ-I)(μ-η 5?: η 5-C5Me5)Yb(C5Me5)]n (1), {[(C5Me5)Sm]3(μ-Cl)4(μ 3-Cl)(μ 3-OH)(THF)}2 (2), {[(C5Me5)Sm]2 (μ-OH)(μ-Cl)4(μ 3-Cl)Mg(THF)2}2 (3), [(C5Me5)2Sm](μ-Cl)6(μ 3-Cl)2(μ 4-Cl)[(C5Me5)Sm]4 (4), {[(C5Me5)Nd]3(μ 3-Cl)4(μ 4-Cl)2(μ 3-O2CPh)2K2(η 6-C7H8)}2 (5), [(C5Me5)Nd(C8H8)]2(μ-dioxane) (6), [(C5Me5)Yb(MeOtBu)]2(μ-η 8?:?η 8-C8H8) (7), [(C5Me5)Dy(μ-I)2]3 (8), and [(C5Me5) Tm(MeCN)6]I2 (9), have been identified by X-ray crystallography. 1 is unusual in that it has a μ-η 5?:?η 5-C5Me5 ring that generates a local bent metallocene environment around ytterbium. Complexes 25 demonstrate the versatility of bridging chlorides in generating a variety of structures for mono(pentamethylcyclopentadienyl) lanthanide halides. Complex 6 shows how dioxane can generate a crystallographically-analyzable complex by bridging two mixed-ligand metallocene units that do not readily crystallize with THF. The structure of 7 shows how methyl tert-butyl ether (MTBE) ligates a lanthanide. Complex 8 is a trimeric cyclopentadienyl lanthanide halide unusual in that it has six bridging halides that roughly define a trigonal prism. Complex 9 constitutes an organometallic example of a lanthanide in which acetonitrile completely displaces iodide counterions.  相似文献   

15.
The study of the K2NiF4 structure by the “method of invariants” leads to the relationship
0.99615 V13BA212
with V = a2c (βB and ψA are invariant values associated with cations B and A) in compounds with K2NiF4 structures. Some values of ψA and examples are proposed.  相似文献   

16.
The amine substituted phosphines (C6H5)2PN(H)CH2CH3 and (C6H5)2PN(H)CH2C6H5 react with C5H5Fe(CO)2CH(C6H5) (OCH3) photolytically to give moderate yields of the four-membered chelate ring complexes C5H5Fe (CO) [(C6H5)2PN (CH2CH3) CH (C6H5)] and C5H5Fe (CO) [(C6H5)2 PN (CH2C6H5)CH(C6H5)], respectively. Photolysis of C5H5Fe(CO)2CH(C6H5) (OCH3) in the presence of (S)-(?)-diphenyl(1-phenylethylamino)phosphine leads to the isolation of C5H5Fe(CO)[(C6H5)2PNC(CH3) (C6H5)]CH2C6H5 which is proposed to arise from a formally 1,3-hydrogen shift rearrangement of an intermediate four-membered chelate ring complex.  相似文献   

17.
A kinetic study of the aqueous persulphate initiated polymerisation of methacrylamide has shown that the rate of polymerisation is represented by the equation Rp = k [M] [I]12 where the overall rate constant, k = 1.3 × 109exp (?18,400/RT) 112mol?12s?1. Chain transfer with monomer, where CM = 5.4 × 10?3 at 60°, is shown to be the dominant transfer step. Comparison with kinetic studies of the analogous acrylamide polymerisation shed doubt on the ‘cage effect’ interpretation of complex orders with respect to monomer. An alternative explanation is proposed.  相似文献   

18.
The structure of guoregine, a new isoquinoline alkaloid from Guatteriaouregou, Annonaceae, has been deduced by spectral analysis and confirmed by an X-ray structure determination. It is the first member of a new class of cularine-related alkaloids (α-gem-dimetyltetradehydrocularines).  相似文献   

19.
Three diruthenium carbonyl complexes, namely (η 3:η 5-C5H4C(CH2)2)Ru2(CO)5 (1), (η 3:η 5-C5H4C(CHCH2)(C2H5))Ru2(CO)5 (2), and (η 1:η 5-C5H4C5H8)Ru2(CO)6 (3), were obtained from the reactions of C5H4C(Me)2, C5H4C(Et)2, and C5H4C(CH2)4, respectively, with Ru3(CO)12 in refluxing xylene. The complexes were characterized by elemental analysis, IR and 1H NMR spectra. Single-crystal X-ray diffraction analysis for complexes 1 and 2 revealed that the fulvene ligands bridge two ruthenium atoms in η 3:η 5 fashion.  相似文献   

20.
The incongruent vaporization reactions of Ta2S and Ta6S have been investigated by mass-loss effusion in the temperature range 1576 to 1902 K. By extrapolation of PS(obs) to equilibrium the enthalpies of the reactions 32Ta2S(s) = 12Ta6S(s) + S(g) and Ta6S = 6 Ta(s) + S(g) were found to be ΔH0298R = 53.0(0.3) · 103K and ΔH0298R = 58.1(0.4) · 103K, respectively. Comparison between the above values, determined by a 2nd law treatment, and 3rd law values was used to derive fef (“free energy function”) values for Ta and S in the compounds. These postulated fef's, which apply only to the elements as present in the compounds measured, are compared to tabulated quantities for the pure solid elements to provide a criterion for 2nd and 3rd law evaluation.  相似文献   

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