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1.
The reactions of 1,1-dichloro-2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-diene (1), magnesium, and R3ECl (E = Si, Ge) under mild conditions (20 °C, THF) gave 1,1-bis(trimethylsilyl)-2,3,4,5-tetraphenyl-1-germacyclopenta-2,-4-diene (2a) and 1,1-bis(triethylgermyl)-2,3,4,5-tetraphenyl-1-germacyclopenta-2,4-diene (2b) respectively. The reaction is versatile and applies to the compounds R3ECl (E = Si, Ge) that do not react with magnesium.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2234–2236, October, 2004.  相似文献   

2.
Unsaturated 1,6‐dicarbonyls like 2,4‐hexadienedial are ring opening products in the OH initiated photo‐oxidation of aromatic hydrocarbons. In the present study, the photolysis of E,Z‐ and E,E‐2,4‐hexadienedial has been investigated under natural sunlight conditions in a large volume outdoor reaction chamber. In the case of the E,Z‐isomer, an extremely rapid isomerization into the E,E‐form was observed. The photoisomerization frequency, relative to that of NO2, was found to be J(E,Z‐2,4‐hexadienedial)/J(NO2) = (0.148 ± 0.012). A more complex photolysis behavior was observed for E,E‐2,4‐hexadienedial. Here, a fast equilibrium preceded a comparably slow photolysis. For the equilibrium reaction, relative frequencies of J(E,E‐2,4‐hexadienedial → EQUI)/J(NO2) = (0.113 ± 0.009) and J(EQUI → E,E‐2,4‐hexadienedial)/J(NO2) = (0.192 ± 0.016) were obtained, giving an equilibrium constant of K = (0.59 ± 0.07). For the photolysis frequencies, ratios of J(E,E‐2,4‐hexadienedial → products)/J(NO2) = J(EQUI → products)/J(NO2) = (1.22 ± 0.45)·10−2 were determined. Qualitative aerosol measurements during the experiments showed that the photolysis of 2,4‐hexadienedials is a source of secondary organic aerosol. In addition to the photolysis study, OH radical reaction rate constants were determined, values of (7.4 ± 1.9)·10−11 and (7.6 ± 0.8)·10−11 cm3 s−1 were obtained for E,Z‐ and E,E‐2,4‐hexadienedial, respectively. The results indicate that the dominant fate of E,Z‐2,4‐hexadienedial in the atmosphere will be photoisomerization, while for E,E‐2,4‐hexadienedial, both photolysis and OH radical reaction will be important sinks. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 689–697, 1999  相似文献   

3.
The Tetracyanoborates M[B(CN)4], M = [Bu4N]+, Ag+, K+ The tetracyanoborate anion is prepared for the first time as the tetrabutylammonium salt by the reaction of [NBu4]BX and BX3 (X = Br, Cl) in toluene with KCN. After purification and recrystallization of the product from CHCl3 colorless and needle size single crystals of [Bu4N][B(CN)4] are formed. After metathesis with AgNO3 the silver salt and subsequently with KBr the potassium salt is prepared. The three salts are characterized by single crystal X‐ray diffraction (Ag[B(CN)4] P 43m, a = 5.732(1) Å, V = 188.3 Å3, Z = 1, R1 = 0.75%; K[B(CN)4] I41/a, a = 6.976(1), c = 14.210(3) Å, V = 691.5 Å3, Z = 4, R1 = 1.90%; [Bu4N][B(CN)4] Pnna, a = 17.765(3), b = 11.650(2), c = 11.454(2) Å, V = 2370.5 Å3, Z = 4, R1 = 6.09%) and by NMR‐, IR‐, Raman‐ as well by UV‐spectroscopy.  相似文献   

4.
K2Br(OH) and Rb2Br(OH): Two New Ternary Alkali Metal Halide Hydroxides with a Pronounced Structural Relationship to KOH resp. RbOH Two isotypic compounds K2Br(OH) and Rb2Br(OH) were prepared in the systems KOH/KBr and RbOH/RbBr. Their structures were determined by single crystal X-ray methods: K2Br(OH): P21/m, Z = 2, a = 6.724(1) Å, b = 4.272(4) Å, c = 8.442(2) Å, β = 108.14(2)°, Z(Fo) = 651 with (Fo)2 ≥ 3σ(Fo)2, Z(parameter) = 28, R/Rw = 0.041/0.047 Rb2Br(OH): P21/m, Z = 2, a = 6.918(3) Å, b = 4.483(2) Å, c = 8.850(5) Å, β = 108.08(6)°, Z(Fo) = 326 mit (Fo)2 ≥ 3σ(Fo)2, Z(parameter) = 27, R/Rw = 0.074/0.082. The compounds are built up by chains of [M2(OH)+] connected via Br?. The structure of the chains as well as their orientation to one another show a pronounced relationship to the structures of the room temperature modifications of the isotypic binary hydroxides KOH and RbOH.  相似文献   

5.
Sr5[NbN4]N (transparent, red single crystals) was synthesized by reaction of Sr2N with Nb under nitrogen at ambient pressure and 1223 K. The crystal structure was solved and refined in the space group Pbcm (no. 57), Z = 4, with lattice constants a = 646.6(3) pm, b = 1792.5(9) pm, c = 729.8(4) pm, and R = 0.019, wR2 = 0.034. The crystal structure contains both isolated tetrahedra [NbN4]7‐ as well as chains of corner sharing octahedra 1(Sr4Sr2/2N7+). Strontium is irregularly coordinated by nitrogen (CN = 4 ‐ 6, Sr‐N: 252.3(4) ‐ 340.8(3) pm); nitrogen is located in a distorted octahedral environment by strontium and niobium (Nb‐N: 194.5(4) ‐ 199.2(2) pm). By formal reduction of the structural building units to their centers a close structural relationship to both the NiAs and the CaSi type structure is evident.  相似文献   

6.
Na5Br(OH)4: Synthesis and Structure of a Compound in the System NaOH/NaBr The pseudobinary system NaOH/NaBr is investigated by X-ray methods. The structure of the compound Na5Br(OH)4 was solved by single crystal data: Na5Br(OH)4: Pnma, Z = 8, a = 11.846(2) Å, b = 18.782(4) Å, c = 6.431(1) Å, Z(Fo) = 1 202 with (Fo)2 ≥ 3σ(Fo)2, Z(parameter) = 100, R/Rw = 0.030/0.035 The compound crystallizes in a new type of structure. Pairs of octahedra around O by 5 Na and 1 H to [Na5(OH)]2 are orientated in such a way to one another that two ions OH? form a parallelogram hinting to unusual bent hydrogen bridge bonding.  相似文献   

7.
WEI Guohua    CAI Chao  DU Yuguo   《中国化学》2009,27(8):1589-1592
Some important precursors (1,6-anhydrous-2-deoxy-2-azido-β-D-glucopyranose (3), 1,6-anhydrous-2-deoxy-2- azido-3,4-di-O-benzyl-β-D-mannopyranose (5), 1,6:2,3-dianhydrous-β-D-glucopyranose (6), 1,6-anhydrous-3- deoxy-3-azido-β-D-glucopyranose (10) and 1,6-anhydrous-2,4-di-O-benzoyl-β-D-glucopyranose (11)) for complex oligosaccharide synthesis were readily prepared from a green starting material 1,6-anhydrous-β-D-glucopyranose in one or two steps with moderate to high yields. These improved methods established herein will greatly facilitate the assembly of some complex oligosaccharides for the biological study.  相似文献   

8.
Strontium Hydroxide Chloride and Strontium Hydroxide Bromide – Preparation, Crystal Structure, and IR and Raman Spectra The partly hitherto unknown compounds Sr(OH)Cl, Sr(OH)Br mC16 and Sr(OH)Br cP16 have been established by both dehydration of the hydrates (Sr(OH)Cl, Sr(OH)Br mC16) and melting together stoichiometric mixtures of Sr(OH)2 and SrCl2 or SrBr2 (Sr(OH)Cl, Sr(OH)Br cP16). The monoclinic polymorph of the bromide is monotropically changed above 650 K (high-temperature X-ray and high-temperature Raman studies) into the cubic modification. Sr(OH)Cl crystallizes in the Cd(OH)Cl structure type (space group P63mc, Z = 2, a = 414.41(2), c = 995.16(10) pm), Sr(OH)Br mC16 and cP16 crystallizing in own structures (C2/m, Z = 4, a = 1100.66(7), b = 429.55(3), c = 726.25(5) pm, β = 106.285(4)°, P213, Z = 4, a = 675.79(2) pm). The structures were refined from X-ray powder diffractograms (Sr(OH)Cl: RI = 11.4%, 4668 observations, Sr(OH)Br mon.: RI = 13%, 1082 observations), neutron powder diffractograms (Sr(OD)Br cub.: RI = 3,8%, 793 observations), and X-ray single-crystal studies, respectively (Sr(OH)Br cub.: R1 = 5.02%, 585 independent reflections). The positions of the hydrogen atoms of Sr(OH)Cl and Sr(OH)Br mon. were determined by the method of minimum cohesive energy. Sr(OH)Cl and Sr(OH)Br mon. crystallize in layered structures with monocapped distorted octahedrally (3 OH and 4 X) coordinated strontium ions. Sr(OH)Br cub. crystallizes in a structure built up of three-dimensional nets, the coordination of Sr, however, corresponds to that of Sr(OH)Cl and Sr(OH)Br mon. IR and Raman spectra are presented and discussed together with the structure data with respect to the strength of the O–H…X hydrogen bonds (stretching modes of matrix isolated OD ions: 2641 cm–1 (Sr(OH)Cl), 2662 cm–1 (Sr(OH)Br mon.), and 2614 cm–1 and 2572 cm–1 (Sr(OH)Br cub.) (295 K)) and the dependence of the librations of the OH ions on the strength of the hydrogen bonds and the packing of the structure. The OH ions of Sr(OH)Br cub. display a temperature dependent disorder between a thermodynamically more stable position with trifurcated hydrogen bonds and one with stronger, almost linear bonds.  相似文献   

9.
Synthesis of Monomeric T‐Shaped Silver(I) Halide Complexes – Crystal Structure Analysis of [P(C6H4CH2NMe2‐2)3]AgBr Treatment of the tetrapodal phosphane P(C6H4CH2NMe2‐2)3 ( 1 ) with equimolar amounts of the silver(I) halides AgX ( 2 a : X = Cl, 2 b : X = Br) produces in tetrahydrofuran at 25 °C the monomeric silver(I) complexes [P(C6H4CH2NMe2‐2)3]AgX with planar coordination at the Ag atoms ( 3 a : X = Cl, 3 b : X = Br) in excellent yields. From complex 3 b a single X‐ray crystal structure analysis was carried out. Mononuclear 3 b crystallizes in the monoclinic space group P21/c with the cell parameters a = 14.504(6), b = 11.034(3), c = 17.604(5) Å, β = 102.86(4)°; V = 2746.6(16) Å3; Z = 4; 2953 observed unique reflections, R1 = 0.0805. Complex 3 b consists of monomeric sub‐units with a planar T‐shaped arrangement formed by the atoms Ag1, N1, P1 as well as Br1, whereby the P1–Ag1–Br1 array is almost linear orientated.  相似文献   

10.
A series of chiral pentane‐2,4‐diyl‐based thioether‐amine ligands [ 4 and 5 ; (R,S)‐ and (S,S)‐R1SCH(CH3)CH2CH(CH3)NHR2, respectively, where 4a R1 = iPr, R2 = Ph; 4b R1 = tBu, R2 = Ph; 4c R1 = 1‐Ad, R2 = Ph; 5a R1 = iPr, R2 = Ph; 5b R1 = tBu, R2 = Ph; 5c R1 = 1‐Ad, R2 = Ph; 5d R1 = iPr, R2 = 4‐MeOC6H4; 5e R1 = iPr, R2 = 4‐MeC6H4; 5f R1 = iPr, R2 = 3,5‐Me2C6H3] with stereogenic S‐ and N‐donor atoms has been prepared starting from cyclic sulfates via optically pure γ‐aminoalcohol or 2,4‐dimethylazetidine intermediates. The synthesis of the novel diastereomerically related ligand sets 4 and 5 was accomplished starting from the same source of chirality. The modular ligand structure and the novel synthetic strategies developed for their synthesis allowed the easy modification of the ligands’ (i) S‐ and (ii) N‐substituents, as well as (iii) the relative stereochemistry within the ligand backbone. Six‐membered [Pd(N,S)Cl2]‐type chelate complexes of the diastereomerically related ligands 4a and 5a were synthesized and characterized by X‐ray crystallography in the solid phase, by density functional theory calculations and in solution by NMR spectroscopy. The coordination of 5a resulted in the formation of a single chair conformation by the stereospecific locking of both stereolabile (N and S) donor atoms. In contrast, compound 4a forms rapidly equilibrating palladium species due to the fast inversion of the sulfur donor. Ligands with stereochemically fixed donor atoms provided robust and efficient catalytic systems that can be effectively applied in alkylene carbonates as green reaction media. Remarkably, the phosphine‐free catalysts are air‐stable, and at room temperature in the presence of moisture gave excellent ee’s (up to 93%) in asymmetric allylation processes thanks to the double stereoselective coordination.  相似文献   

11.
The complete assignment of the signals in the13C NMR spectra of 2,3,4,5-tetraphenyl-1-R1,R2-1-silacyclopenta-2,4-dienes (R1=R2=H, Me) and of the dianion of lithium salt [(PhC)4Si]2−·2Li+ was carried out by 2D NMR spectroscopy. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 216–218, January, 1999.  相似文献   

12.
Four chiral polymers P-1, P-2, P-3 and P-4 were synthesized by the polymerization of (S)-2,2'-dioctoxy-1,1'- binaphthyl-6,6'-boronic acid (S-M-3) with (S)-6,6'-dibromo-1,1'-binaphthol (S-M-1), (R)-6,6'-dibromo-1,1'- binaphthol (R-M-1), (S)-3,3'-diiodo-1,1'-binaphthol (S-M-2) and (R)-3,3'-diiodo-1,1'-binaphthol (R-M-2) under Pd-catalyzed Suzuki reaction, respectively. All four polymers can show good solubility in some common solvents due to the nonplanarity of the polymers in the main chain backbone and flexible alkyl groups in the side chain. The analysis results indicate that specific rotation and circular dichroism (CD) spectral signals of the alternative S-S chiral polymers P-1 and P-3 are larger than those of S-R chiral polymers P-2 and P-4, but their UV-Vis and fluorescence spectra are almost similar. The results of asymmetric enantioselectivity of four polymers for diethylzinc addition to benzaldehyde indicate that catalytically active center is (R) or (S)-1, 1'-binaphthol moieties.  相似文献   

13.
The NCN‐pincer Pd‐complex‐bound norvalines Boc‐D /L ‐[PdCl(dpb)]Nva‐OMe ( 1 ) were synthesized in multigram quantities. The molecular structure and absolute configuration of 1 were unequivocally determined by single‐crystal X‐ray structure analysis. The robustness of 1 under acidic/basic conditions provides a wide range of N‐/C‐terminus convertibility based on the related synthetic transformations. Installation of a variety of functional groups into the N‐/C‐terminus of 1 was readily carried out through N‐Boc‐ or C‐methyl ester deprotection and subsequent condensations with carboxylic acids, R1COOH, or amines, R2NH2, to give the corresponding N‐/C‐functionalized norvalines R1‐D /L ‐[PdCl(dpb)]Nva‐R2 2 – 9 . The dipeptide bearing two Pd units 10 was successfully synthesized through the condensation of C‐free 1 with N‐free 1 . The robustness of these Pd‐bound norvalines was adequately demonstrated by the preservation of the optical purity and Pd unit during the synthetic transformations. The lipophilic Pd‐bound norvalines L ‐ 2 , Boc‐L ‐[PdCl(dpb)]Nva‐NH‐n‐C11H23, and L ‐ 4 , n‐C4H9CO‐L ‐[PdCl(dpb)]Nva‐NH‐n‐C11H23, self‐assembled in aromatic solvents to afford supramolecular gels. The assembled structures in a thermodynamically stable single crystal of L ‐ 2 and kinetically stable supramolecular aggregates of L ‐ 2 were precisely elucidated by cryo‐TEM, WAX, SAXS, UV/Vis, IR analyses, and single‐crystal X‐ray crystallography. An antiparallel β‐sheet‐type aggregate consisting of an infinite one‐dimensional hydrogen‐bonding network of amide groups and π‐stacking of PdCl(dpb) moieties was observed in the supramolecular gel fiber of L ‐ 2 , even though discrete dimers are assembled through hydrogen bonding in the thermodynamically stable single crystal of L ‐ 2 . The disparate DSC profiles of the single crystal and xerogel of L ‐ 2 indicate different thermodynamics of the molecular assembly process.  相似文献   

14.
Nest‐shaped cluster [CuBr(bpy)2][MoOS3Cu3Br2(bpy)] was synthesized by the treatment of (NH4)2 MOO2S2, CuBr and Et4NBr with bpy (2,2′‐bipyridyl) in CH3CN. Its structure has been characterized by X‐ray diffraction; monoclinic, space group P21/n ‐ with a = l.0092(4), b = 2.6347(7), c = 1.4087(3) nm, β = 91.744(9)°, V = 3.7438 nm3, Z=4, and final R = 0.051, Rw = 0.053. It consists of two parts: nest‐shaped structural unit [MoOS3Cu3Br2(bpy)] and complex ion [CuBr(bpy)2]+. We determined its third‐order nonlinear optical (NLO) properties with a 7‐ns pulsed laser at 532 nm. The duster exhibits strong NLO refractive behavior, its third‐order susceptibility χ(3) was calculated to be 2.7 · 10?11 esu in a 7.8 · 10?4 g/cm3 DMF solution. The value is comparable to those of inorganic dusters.  相似文献   

15.
The reaction of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT, 1 ) with 4‐methoxy benzaldehyde and 3‐methoxybenzaldehyde in methanol led to the iminic derivatives 4‐(4‐methoxybenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)thione ( 2 , L1) and 4‐(3‐methoxybenzylideneamino)‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione ( 3 , L2). The reaction of the latter with [(PPh3)2CuCl] in methanol solution gave the first CuI complex of 3 , [(PPh3)2CuCl(L2)] ( 4 ) and in chloroform solution the complex [(PPh3)2CuCl(L2)]·2CHCl3 ( 5 ). All compounds were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for 2 at ?80 °C: space group P21/c with a = 1351.3(3), b = 399.4(1), c = 2225.2(5) pm, β = 96.50(2)°, Z = 4, R1 = 0.0667, for 3 at ?80 °C: space group R3c with a = b = 3020.4(2), c = 708.2(1) pm, Z = 18, R1 = 0.0435, for 4 at ?80 °C: space group P21/c with a = 1427.8(1), b = 1129.0(1), c = 2622.8(2) pm, β = 97.19(1)°, Z = 4, R1 = 0.0517 and for 5 at ?80 °C: space group with a = 1280.5(1), b = 1316.1(1), c = 1731.4(1) pm, α = 78.14(1)°, β = 86.06(1)°, γ = 64.69(1)°, Z = 2, R1 = 0.0525.  相似文献   

16.
Synthesis and Crystal Structure of (PPh4)3[Re2NCl10] The rhenium(V) nitrido complex (PPh4)3[Re2NCl10] ( 1 ) is obtained from the reaction of (PPh4)[ReNCl4] with 1, 3‐dioxan‐(2‐ylmethyl)diphenyl phosphine in CH2Cl2/CH3CN in form of orange red crystals with the composition 1 ·2CH2Cl2 crystallizing in the triclinic space group P1¯ with a = 1210.7(2), b = 1232.5(1), c = 2756.3(5) pm, α = 99.68(1)°, β = 100.24(1)°, γ = 98.59(1)° and Z = 2. The crystal structure contains two symmetry independent, centrosymmetrical complex anions [Re2NCl10]3‐ with a symmetrical nitrido bridge Re=N=Re and distances Re(1) ‐ N(1) = 181.34(5) and Re(2) ‐ N(2) = 181.51(4) pm.  相似文献   

17.
First synthetic attempts towards the so‐far‐unknown calicene (=5‐(cycloprop‐2‐en‐1‐ylidene)cyclopenta‐1,3‐diene) precursors 3‐(cyclopenta‐2,4‐dien‐1‐ylidene)tricyclo[3.2.2.22,4]nona‐6,8‐diene ( 4 ; Scheme 1), 1,4‐di(cyclopenta‐2,4‐dien‐1‐ylidene)cyclohexa‐2,5‐diene ( 5 ; Scheme 2), and (2‐bromocycloprop‐1‐en‐1‐yl)cyclopentadiene ( 6 ; X=Br; Scheme 5) are reported, which would represent very attractive compounds for gas‐phase pyrolysis ( 4 ), matrix photolysis ( 5 ), and low‐temperature HBr eliminations in solution ( 5 ).  相似文献   

18.
The reaction of 4‐amino‐1,2,4‐Δ2‐triazoline‐5‐thione (ATT, 1 ) with AgNO3 in methanol led to the complex [Ag(ATT)2]NO3 ( 2 ). 2 was characterized by elemental analyses, 1H NMR, IR, and Raman spectroscopy as well as single‐crystal X‐ray diffraction. The molecular structure of 1 was also determined by single crystal X‐ray analysis. Crystal data for 1 at ?80 C: space group C2/c with a = 2107.4(2), b = 1425.1(1), c = 688.4(1) pm, β = 104.55(1)°, Z = 16, R1 = 0.0514, crystal data for 2 at ?80 °C: space group P21/c with a = 675.7(1), b = 1321.1(1), c = 1311.2(1) pm, β = 90.03(1)°, Z = 4, R1 = 0.0437.  相似文献   

19.
The reaction of 4‐amino‐6‐methyl‐1,2,4‐triazin‐thione‐5‐one (H2AMTTO, 1 ) with 4‐chlorobenzaldhyde led to the corresponding iminic compound {(4‐[(4‐chloro‐benzylidene)‐amino]‐6‐methyl‐3‐thioxo[1,2,4]‐triazin‐3,4‐dihydro(2H)‐5‐one), CAMTTO ( 2 ). Treatment of 2 with copper(I) chloride in chloroform gave the dimeric complex [{(CAMTTO)2CuCl}2]·2CHCl3 ( 3 ). Treatment of 2 with copper(I) chloride and silver(I) nitrate in the presence of the co‐ligand triphenylphophane gave the complexes [(CAMTTO)CuCl(PPh3)2] ( 4 ) and [(CAMTTO)Ag(PPh3)2]NO3·2CHCl3 ( 5 ). All compounds have been characterized by elemental analyses, 1H NMR spectroscopy, IR spectroscopy, and partly by mass spectrometry and X‐ray diffraction studies. In addition 4 and 5 have been characterized by 31P{1H} NMR spectroscopy. Crystal data for 2 at ?80 °C: monoclinic, space group P21/c, a = 1370.3(1), b = 767.8(1), c = 1268.7(1) pm, β = 107.12(1)°, Z = 4, R1 = 0.0379; for 3 at ?80 °C: monoclinic, space group P21/c, a = 1442.6(2), b = 878.8(1), c = 2558.7(3) pm, β = 95.31(1)°, Z = 2, R1 = 0.0746; for 4 at ?80 °C: triclinic, space group , a = 1287.9(1), b = 1291.7(1), c = 1359.5(1) pm, α = 90.44(1)°, β = 94.81(1)°, γ = 107.54(1)°, Z = 2, R1 = 0.0359 and for 5 at ?80 °C: triclinic, space group , a = 1060.5(1), b = 1578.2(2), c = 1689.6(2) pm, α = 87.70(1)°, β = 86.66(1)°, γ = 76.84(1)°, Z = 2, R1 = 0.0487.  相似文献   

20.
Two new highly oxidized humulane sesquiterpenes, mitissimols F ( 1 ) and G ( 2 ), were isolated from the fruiting bodies of Lactarius mitissimus. Their structures were elucidated by using extensive spectroscopic techniques including 1D‐ and 2D‐NMR experiments. The absolute configuration of mitissimol F ( 1 ) was determined by 1H‐NMR resolution of its diastereoisomeric α‐methoxy‐α‐(trifluoromethyl)benzeneacetates (MTPA). It was shown to be (1S,3E,6S,8R,9R,10S,11R)‐8,9 : 10,11‐diepoxy‐1,6‐dihydroxyhumul‐3‐en‐5‐one (=(1S,2R,4R,6S,8E,11S,12R)‐6,11‐dihydroxy‐1,6,10,10‐tetramethyl‐3,13‐dioxatricyclo[10.1.0.02,4]tridec‐8‐en‐7‐one).  相似文献   

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