3-亚甲基异苯并呋喃-1(3H)-酮的合成

以邻甲基苯甲酸甲酯为原料,经过自由基溴代,Wittig反应,酯水解反应,得到邻乙烯基苯甲酸;随后发生环氧化反应,环合反应得到3-羟甲基异苯并呋喃-1(3H)-酮;再发生亲核取代和消除反应合成了3-亚甲基异苯并呋喃-1(3H)-酮。目标产物在空气中长期放置没有发生二聚。化合物结构用1H NMR、13C NMR和IR表征。     

三亚甲基碳酸酯和己内酯生物可降解共聚物序列结构的二维核磁分析

以辛酸亚锡[Sn(Oct)2]为催化剂、乙二醇为引发剂,通过本体开环共聚,合成了己内酯(CAP)与三亚甲基碳酸酯(TMC)的共聚物。采用1H、13C核磁共振及同核二维相关谱(gCOSY)、13C-1H异核相关谱(gHSQC)和13C-1H异核远程相关谱(gHMBC)等二维核磁共振(2D NMR)技术,对所合成的聚合物进行了序列微结构表征,找出了聚合物分子链中序列连接方式,并完成了1H和13C NMR谱带的归属。     

胺烷基二茂铁衍生物研究(Ⅱ)——(N、N-二乙基)胺甲基二茂铁钯配合物与烯烃的反应

本文报道了(N,N-二乙基)胺甲基二茂铁钯配合物的合成及其与烯烃的反应,以及(N,N-二乙基)胺甲基二茂铁(Ⅰ)、钯配合物(Ⅱ)和反应产物的波谱性质。 1 实验 1.1 仪器 IR光谱用Shimadzu IR-450红外分光光度计测定,固体用KBr压片,液体用CsI涂片。Ⅰ和反应产物的~1H NMR谱用Varian EM-390核磁共振仪测定,氘代氯仿作溶剂;Ⅱ用Varian XL-200核磁共振仪测定;氘代二甲亚砜作溶剂。均以TMS作内标。     

NMR鉴定季戊四醇丙烯酸酯混合物中的组分

气相色谱-质谱联用(GC-MS)分析季戊四醇丙烯酸酯混合物,得到混合物的相关信息;将季戊四醇丙烯酸酯混合物湿法装填硅胶柱,分别用正己烷、氯仿、乙酸乙酯、乙醇等溶剂进行洗脱;将特定编号的分离物和季戊四醇丙烯酸酯混合物的GC-MS总离子流图进行对照,用核磁共振(NMR)对选取特定编号的分离物做1H-NMR谱、13C-NMR谱、1H-1H COSY谱、13C-1H COSY谱、HMBC谱,确认混合物中的未知组分为三羟甲基丙烷三丙烯酸酯。     

水相中碱促进的2-氨基苯并噁唑衍生物的合成

4-取代邻氨基苯酚(1)与取代异硫氰酸酯(2)在NaHCO3促进下,通过"一锅法"合成了16个2-氨基苯并噁唑衍生物(其中11个为新化合物),其结构经1H NMR,13C NMR和HR-MS表征。最佳反应条件为:1 0.5mmol,2 1.2 eq,NaHCO32 eq,H2O为溶剂,于80℃反应2 h,产率最高达96%。     

选择性合成双[噻吩并[2,3-d]嘧啶-4(3H)-酮]

以2-氨基-4-三氟甲基-5-甲基-噻吩-3-羧酸乙酯(1)为起始原料制得膦亚胺2.在碳酸钾的催化下,膦亚胺2与芳基异氰酸酯和伯二胺的氮杂Wittig反应制得嘧啶环上2,2’取代的双[噻吩并[2,3-d]嘧啶-4(3H)-酮]3;膦亚胺2与烷基异氰酸酯和伯二胺的氮杂Wittig反应制得嘧啶环上3,3’取代的双[噻吩并[2,3-d]嘧啶-4(3H)-酮]4.化合物3的核磁共振氢谱表明关环反应在嘧啶环的2,2’位;化合物4的核磁共振氢谱表明关环反应在嘧啶环的3,3’位.对合成反应机理的推导及目标产物核磁共振氢谱数据的分析解释了此合成反应的选择性.     

三乙胺催化的双环氮杂锡氧烷配合物氘代反应研究

全面研究了三乙胺催化下双环氮杂锡氧烷配合物α 氢的氘代反应 .首先考察了三乙胺催化下双环氮杂锡氧烷配合物α 氢的氘代反应的核磁共振谱 ,研究发现 :在三乙胺存在下 ,有机锡配合物α 氢可以与CD3 OD溶剂发生氘代反应 ,其核磁共振峰强度随着时间而衰减 ,且氘代反应速率与三乙胺的浓度有关 .其次 ,利用核磁共振技术测定氘代反应速率 ,其反应表观速率常数为 2 .0× 1 0 -4 ～ 1 0 .0× 1 0 -4 s-1,推导了其动力学机理并讨论了取代基对氘代反应速率的影响 .     

用核磁共振方法表征6(8)氨基-3H苯[1,2]氧嗪-1,4-二酮

用一维1HNMR、13CNMR方法研究了6(8)氨基-3H苯[1,2]氧嗪-1,4二-酮的结构,并通过二维1H-1H同核相关谱(COSY)、13C-1H异核相关谱(HMQC)及13C-1H异核远程相关谱(HMBC)进一步确定了该类化合物的1H谱和13C谱中各谱峰的归属,为研究同类化合物表征提供了依据。     

5-(S)-孟氧基-3,4-二卤-2(5H)-呋喃酮与4-硝基邻苯二胺的Michael加成―消除反应

在Et3N作为碱的温和条件下,5-(S)-孟氧基-3,4-二卤-2(5H)-呋喃酮与芳香胺4-硝基邻苯二胺发生串联的Michael加成―消除反应,生成了新的含有苯环结构的5-孟氧基-4-氨基-3-卤-2(5H)-呋喃酮类化合物。新化合物的结构通过紫外―可见光谱(UV-Vis)、红外光谱(IR)、质谱(MS)、核磁共振氢谱(1H NMR)、核磁共振碳谱(13C NMR)和元素分析等表征证实。该多环结构卤代2(5H)-呋喃酮化合物的合成,能为某些多官能团的结构复杂的2(5H)-呋喃酮化合物的合成提供新途径。     

新喜树碱衍生物的核磁共振谱分析与结构鉴定

以20(S)-喜树碱(CPT)为起始原料,对其进行结构修饰,合成了一种新的喜树碱衍生物CPT-A.并利用1D(~1H、~(13)C和DEPT135)和2D(异核单量子相关谱和异核多碳相关谱)核磁共振(NMR)技术对该化合物进行了结构确定,详细归属了CPT-A~1H和~(13)C NMR谱的化学位移,喜树碱骨架的指认结果与文献报道基本一致,并发现喜树碱骨架6位碳与取代基苯环3’位碳的化学位移相同,谱峰完全重叠,这在~(13)C谱中是不常见的.研究结果可为喜树碱类天然产物的发现和结构鉴定提供NMR数据支持和方法指引.     

Study on conformation interconversion of 3-alkyl-4-acetyl-3,4-dihydro-2H-1,4-benzoxazines from dynamic NMR experiments and ab initio density functional calculations

Variable-temperature NMR experiments and ab initio density functional calculations were carried out to investigate the conformation interconversion of novel chiral 3-alkyl-3,4-dihydro-2H-benzo[1,4]oxazine derivatives. With CDCl3 as the solvent, the coalescence temperatures of H2, H3, H11, and H19 of product 1 are about 289, 304, 292, and 316 K, with the corresponding activation free energies at 58.0 +/- 6.7, 60.9 +/- 7.1, 58.3 +/- 6.8, and 59.6 +/- 6.9 kJ.mol(-1), respectively. When dimethyl sulfoxide (DMSO-d6) was used as the solvent, 1H and 13C NMR signals were completely assigned at 375 K. The effects of solvent and temperature were investigated through a polarizable continuum model. At each theoretical level (MP2 or B3LYP), the changing tendencies of the calculated activation free energies and interconversion rates agree well with those of the NMR results. In addition, the interconversion rate at each specified temperature was calculated to be about 1.5 times faster in DMSO-d6 than in CDCl3. Accordingly, we failed to observe the coalescence phenomena of H3 and H19 in DMSO-d6 by NMR measurements from 296 to 375 K. The substitution effect at the R1-R5 positions was considered using density functional calculations, with the activation barriers decreasing as follows: product 6 > 3 > 1 > 7 > 2. This sequence is consistent with that of the reaction heats, except for product 7, implying that the interconversion processes may be thermodynamically controlled. Surprisingly, the substituted groups near the acetyl group in product 2 and 7 do not elevate the activation barrier but, instead, lower it somewhat, with the possible reasons for this provided in the paper.     

Unambiguous NMR spectral assignments of salvinorin A

The complete assignments of the (1)H and (13)C NMR spectra of the hallucinogenic neoclerodane diterpenoid salvinorin A were determined in three different NMR solvents using HSQC, HMBC and COSY. Solvent systems are described that allow the resolution of all (1)H signals. Virtual coupling was observed for the protons at C-2, C-3 and C-4 in the 600 MHz (1)H spectrum in CDCl(3). The complete assignments of the (1)H and (13)C NMR spectra of salvinorin B are also reported.     

Synthesis and fluorescence study of 3-aminoalkylamidonapthalimides

A new series of fluorescent 3-aminoalkylamidonapthalimides were synthesized starting form 1,8-naphthalic anhydride. The structure of these compounds was characterized by ¹H NMR, ¹³C NMR, IR and Mass spectral analysis. The solvent effect on ¹H and ¹³C NMR of these compounds was studied in CDCl₃, CDCl₃:DMSO-d₆ (7:3, v/v) and DMSO-d₆. NMR chemical shift of the ortho and para protons and meta carbons of naphthalene ring showed maximum variation on moving from CDCl₃ to DMSO-d₆. In CDCl₃ solvent naphthalene ring may exist in slightly puckered form while in DMSO-d₆ it attains maximum planar configuration. Fluorescent properties of the title compounds and their precursors were investigated in different solvents like chloroform, ethanol, acetonitrile, acetone, DMSO and water. 3-Aminoalkylamidonapthalimides exhibited improved fluorescence than their precursors. Cyclic amino derivatives yielded higher fluorescence quantum efficiency in protic solvents, ethanol and water. Acylic amino derivatives yielded high fluorescence quantum efficiency in chloroform solvent. The maximum fluorescence quantum yield up to 0.14 was found for butyl amine derivative in chloroform solvent. In general proton accepting nucleophilic solvents like acetone and DMSO quenched the fluorescence.     

Ureidopyrimidinones incorporating a functionalizable p-aminophenyl electron-donating group at C-6

[structure: see text] 2-Ureido-4-[1H]-pyrimidinones have been reported to dimerize via quadruple hydrogen bonding systems with dimerization constants >10(6) M(-1) in CDCl3. The dimerization constant, K(dim), is dependent on the solvent as well as the ring-substituents present, where previously alkyl (e.g., R1 = Me) and aromatic moieties (e.g., R1 = p-NO2C6H4, R1 = C6H2(OC13H27)3) have been incorporated at the C-6 position. To assess the influence of alternative, functionalizable, electron-donating groups on the dimerization motif and tautomeric distribution of isomers, the synthesis of compounds possessing aminophenyl functionality at the C-6 position has been achieved. NMR spectroscopy chemical shift analysis revealed that compound 2 (R1 = p-NH2C6H4, R2 = C6H13) existed as the 2-ureido-4-pyrimidinol dimeric DADA array in DMSO-d6, where a dimerization constant of 46 M(-1) was determined. This is the first time that a ureidopyrimidinone quadruple hydrogen bonding DADA array has been observed in pure DMSO, a highly polar solvent. The azo-derivative 5 of compound 2 was prepared which also adopted the pyrimidin-4-ol form in DMSO-d6. Compounds 7, 10 and 11 were then synthesized containing a more hydrophilic PEG unit in the lateral chain and the tautomeric distributions were determined.     

1-酰氧(胺)-2,8,9-三氧杂-5-氮杂-1-锡杂三环[3.3.3.01.5]十一烷的合成和结构研究

合成了１４个新化合物：１－酰氧（胺）基－２，８，９－三氧杂－５－氮杂－１－锡杂三环［３．３．３．０１．５］十一烷．由ＩＲ、１ＨＮＭＲ、１３ＣＮＭＲ和１１９ＳｎＮＭＲ及元素分析确定其结构．该类化合物在ＣＤＣｌ３中可能形成六配位化合物，而在ＤＭＳＯ中，溶剂分子参与Ｓｎ原子配位，聚合体解聚为六配位化合物．     

1H chemical shifts in NMR: Part 23, the effect of dimethyl sulphoxide versus chloroform solvent on 1H chemical shifts

The 1H chemical shifts of 124 compounds containing a variety of functional groups have been recorded in CDCl3 and DMSO-d6 (henceforth DMSO) solvents. The 1H solvent shift Delta delta = delta(DMSO) - delta(CDCl3) varies from -0.3 to +4.6 ppm. This solvent shift can be accurately predicted (rms error 0.05 ppm) using the charge model of alpha, beta, gamma and long-range contributions. The labile protons of alcohols, acids, amines and amides give both, the largest solvent shifts and the largest errors. The contributions for the various groups are tabulated and it is shown that for H.C.C.X gamma-effects (X = OH, NH, =O, NH.CO) there is a dihedral angle dependence of the gamma-effect. The group contributions are discussed in terms of the possible solvent-solute interactions. For protic hydrogens, hydrogen bonding is the dominant interaction, but for the remaining protons solvent anisotropy and electric field effects appear to be the major factors.     

Studies of some monocyclic and bicyclic arylacetonitriles

The high-resolution (1)H, (13)C, (1)H-(1)H COSY and (1)H-(13)C COSY NMR spectra have been recorded in CDCl(3) for arylacetonitriles 1-12 and analyzed. The arylacetonitriles 3-7 exist in two isomeric forms E (methyl group is anti to cyano group) and Z (the methyl group is syn to cyano group) in solution. Normal chair conformation with equatorial orientations of phenyl rings at C-2 and C-6 for monocyclic nitriles 1 and 2, epimeric chair structure EC (axial configuration of methyl group at C-3) for both the E and Z isomers of arylacetonitrile derivatives (3-7) and a distorted boat form, B(3), for the N-acylacetonitrile derivatives (8-10) have been proposed based on NMR data. The bicyclic nitriles 11 and 12 exist in twin chair conformations in solution. DFT calculations and chemical shifts also support these conformations. Geometry optimizations for 1-12 were carried out according to density functional theory using B3LYP/6-31G(d,p) basis set and for 1 and 8 the theoretical geometrical parameters have been compared with those of single crystal measurements.     

1H chemical shifts in NMR: Part 22-Prediction of the 1H chemical shifts of alcohols, diols and inositols in solution, a conformational and solvation investigation

The (1)H NMR spectra of a number of alcohols, diols and inositols are reported and assigned in CDCl(3), D(2)O and DMSO-d(6) (henceforth DMSO) solutions. These data were used to investigate the effects of the OH group on the (1)H chemical shifts in these molecules and also the effect of changing the solvent. Inspection of the (1)H chemical shifts of those alcohols which were soluble in both CDCl(3) and D(2)O shows that there is no difference in the chemical shifts in the two solvents, provided that the molecules exist in the same conformation in the two solvents. In contrast, DMSO gives rise to significant and specific solvation shifts. The (1)H chemical shifts of these compounds in the three solvents were analysed using the CHARGE model. This model incorporates the electric field, magnetic anisotropy and steric effects of the functional group for long-range protons together with functions for the calculation of the two- and three-bond effects. The long-range effect of the OH group was quantitatively explained without the inclusion of either the C--O bond anisotropy or the C--OH electric field. Differential beta and gamma effects for the 1,2-diol group needed to be included to obtain accurate chemical shift predictions. For DMSO solution the differential solvent shifts were calculated in CHARGE on the basis of a similar model, incorporating two-bond, three-bond and long-range effects. The analyses of the (1)H spectra of the inositols and their derivatives in D(2)O and DMSO solution also gave the ring (1)H,(1)H coupling constants and for DMSO solution the CH--OH couplings and OH chemical shifts. The (1)H,(1)H coupling constants were calculated in the CHARGE program by an extension of the cos(2)phi equation to include the orientation effects of electronegative atoms and the CH--OH couplings by a simple cos(2)phi equation. Comparison of the observed and calculated couplings confirmed the proposed conformations of myo-inositol, chiro-inositol, quebrachitol and allo-inositol. The OH chemical shifts were also calculated in the CHARGE program. Comparison of the observed and calculated OH chemical shifts and CH.OH couplings suggested the existence of intramolecular hydrogen bonding in a myo-inositol derivative.     

Synthesis and NMR spectroscopic studies of allylsulfanyl-N1-alkyl-N4-phenyl-1,4-phenylenediamines and their cyclization products, 2,3-dihydro-1-benzothiophenes and thiochromans

Regioselective addition of allylthiol at the C-3 position adjacent to the nitrogen carrying the phenyl group of the 1,4-phenylenediamine moiety of compounds 1-4 was rigorously confirmed by 1D NOE difference in combination with gHMBC experiments. The structures of 1,4-phenylenediamines 1-4, allylsulfanyl-N1-alkyl-N4-phenyl-1,4-phenylenediamines 5-8 and cyclization products 9-14 were completely analyzed in both CDCl3 and DMSO-d6 solutions. The 1H and 13C NMR spectra of 10 and 11, which contain two chiral centers, exhibit duplication for several signals, indicating the existence of two diastereomeric forms. The full structures of 5 and 9 were unambiguously confirmed by x-ray crystallography. The 1H and 13C NMR spectra of all compounds were assigned using one- and two-dimensional NMR techniques (APT, DEPT, 1D NOE difference, COSY, NOESY, HETCOR, gHMQC and gHMBC).     

NMR位移试剂Eu(fod)~4^-对锍盐^1H和^1^3C NMR的影响

合成了八种新的四氟硼酸二甲基苯基锍，用元素分析和核磁共振对其结构进行了表征。研究了以CDCl~3为溶剂，NMR位移试剂Eu(fod)~4^-对所合成锍盐的^1H和^1^3C NMR的影响。结果表明，Eu(fod)~4^-是一个对锍盐非常有效的位移试剂，且Eu(fod)~4^-对二甲基苯基锍盐之甲基的^1H和^1^3C NMR的位移呈线性关系。