碳谱中的溶剂峰
核磁共振波谱碳谱中常见的杂峰
核磁共振（Nuclear Magnetic Resonance, NMR）波谱和碳谱是化学分析中常用的技术，通过观察分子中各种元素的NMR信号，可以得到有关分子结构和化学环境的信息。
然而，在实际应用中，我们常常会遇到一些杂峰的情况，这些杂峰可能来自于实验条件、溶剂、杂质或者实际样品本身。
本文将深入探讨核磁共振波谱碳谱中常见的杂峰，帮助读者更好地理解和应对这些情况。
### 1. 杂峰的定义和分类在NMR实验中，杂峰指的是与样品本身无关的信号，它们可能来自于溶剂、杂质或者实验条件。
根据来源和特点的不同，杂峰可以被分为几种类型：- 溶剂峰：来自于NMR溶剂的信号，通常会在碳谱中出现。
- 杂质峰：来自于实际样品中的杂质或杂质产生的信号。
- 仪器峰：来自于NMR仪器本身或实验条件的信号。
### 2. 溶剂峰溶剂峰是碳谱中常见的杂峰之一。
在实验中，我们常常会选择含有丰富氢原子的氘代溶剂（如CDCl3、DMSO等）作为NMR溶剂，以减少溶剂对样品的干扰。
然而，即使是氘代溶剂中也可能存在少量的质子，这些质子会在碳谱中表现为杂峰，通常出现在4.7-5.3 ppm的范围内。
当我们观察样品的碳谱时，如果出现了明显的溶剂峰，需要格外注意并鉴别溶剂峰与样品峰的区别。
### 3. 杂质峰杂质峰是另一种常见的杂峰类型。
在实际的样品中，可能会存在一些杂质，这些杂质的信号会与样品的信号重叠，导致谱图解析困难。
针对这种情况，我们可以通过一些技术手段（如纯化、预处理等）来尽量减少杂质的影响，从而获得更清晰的NMR谱图。
### 4. 仪器峰仪器峰是来源于NMR仪器本身或实验条件的信号。
这些峰可能会在谱图中表现为不规则的突起或者背景波动，通常会引起谱图的杂乱和干扰。
在实验中，我们可以通过调整仪器参数、检修仪器、调节实验条件等方式来尽量减少仪器峰的出现。
### 5. 如何应对杂峰对于NMR谱图中的杂峰，尤其是溶剂峰和杂质峰，我们可以采取一些措施来应对，以确保样品的分析质量和准确性：- 选择纯净的溶剂，并严格控制NMR实验条件，以减少溶剂峰的出现。
核磁共振氢谱碳谱各种溶剂峰
show their degree of variability.Occasionally,in order to distinguish between peaks whose assignment was ambiguous,a further1-2µL of a specific substrate were added and the spectra run again.Table1.1H NMR Dataproton mult CDCl3(CD3)2CO(CD3)2SO C6D6CD3CN CD3OD D2O solvent residual peak7.26 2.05 2.507.16 1.94 3.31 4.79 H2O s 1.56 2.84a 3.33a0.40 2.13 4.87acetic acid CH3s 2.10 1.96 1.91 1.55 1.96 1.99 2.08 acetone CH3s 2.17 2.09 2.09 1.55 2.08 2.15 2.22 acetonitrile CH3s 2.10 2.05 2.07 1.55 1.96 2.03 2.06 benzene CH s7.367.367.377.157.377.33tert-butyl alcohol CH3s 1.28 1.18 1.11 1.05 1.16 1.40 1.24 OH c s 4.19 1.55 2.18tert-butyl methyl ether CCH3s 1.19 1.13 1.11 1.07 1.14 1.15 1.21 OCH3s 3.22 3.13 3.08 3.04 3.13 3.20 3.22 BHT b ArH s 6.98 6.96 6.877.05 6.97 6.92OH c s 5.01 6.65 4.79 5.20ArCH3s 2.27 2.22 2.18 2.24 2.22 2.21ArC(CH3)3s 1.43 1.41 1.36 1.38 1.39 1.40chloroform CH s7.268.028.32 6.157.587.90 cyclohexane CH2s 1.43 1.43 1.40 1.40 1.44 1.451,2-dichloroethane CH2s 3.73 3.87 3.90 2.90 3.81 3.78 dichloromethane CH2s 5.30 5.63 5.76 4.27 5.44 5.49diethyl ether CH3t,7 1.21 1.11 1.09 1.11 1.12 1.18 1.17 CH2q,7 3.48 3.41 3.38 3.26 3.42 3.49 3.56 diglyme CH2m 3.65 3.56 3.51 3.46 3.53 3.61 3.67 CH2m 3.57 3.47 3.38 3.34 3.45 3.58 3.61OCH3s 3.39 3.28 3.24 3.11 3.29 3.35 3.37 1,2-dimethoxyethane CH3s 3.40 3.28 3.24 3.12 3.28 3.35 3.37 CH2s 3.55 3.46 3.43 3.33 3.45 3.52 3.60 dimethylacetamide CH3CO s 2.09 1.97 1.96 1.60 1.97 2.07 2.08 NCH3s 3.02 3.00 2.94 2.57 2.96 3.31 3.06NCH3s 2.94 2.83 2.78 2.05 2.83 2.92 2.90 dimethylformamide CH s8.027.967.957.637.927.977.92 CH3s 2.96 2.94 2.89 2.36 2.89 2.99 3.01CH3s 2.88 2.78 2.73 1.86 2.77 2.86 2.85 dimethyl sulfoxide CH3s 2.62 2.52 2.54 1.68 2.50 2.65 2.71 dioxane CH2s 3.71 3.59 3.57 3.35 3.60 3.66 3.75 ethanol CH3t,7 1.25 1.12 1.060.96 1.12 1.19 1.17 CH2q,7d 3.72 3.57 3.44 3.34 3.54 3.60 3.65OH s c,d 1.32 3.39 4.63 2.47ethyl acetate CH3CO s 2.05 1.97 1.99 1.65 1.97 2.01 2.07C H2CH3q,7 4.12 4.05 4.03 3.89 4.06 4.09 4.14CH2C H3t,7 1.26 1.20 1.170.92 1.20 1.24 1.24 ethyl methyl ketone CH3CO s 2.14 2.07 2.07 1.58 2.06 2.12 2.19C H2CH3q,7 2.46 2.45 2.43 1.81 2.43 2.50 3.18CH2C H3t,7 1.060.960.910.850.96 1.01 1.26 ethylene glycol CH s e 3.76 3.28 3.34 3.41 3.51 3.59 3.65“grease”f CH3m0.860.870.920.860.88CH2br s 1.26 1.29 1.36 1.27 1.29n-hexane CH3t0.880.880.860.890.890.90CH2m 1.26 1.28 1.25 1.24 1.28 1.29HMPA g CH3d,9.5 2.65 2.59 2.53 2.40 2.57 2.64 2.61 methanol CH3s h 3.49 3.31 3.16 3.07 3.28 3.34 3.34 OH s c,h 1.09 3.12 4.01 2.16nitromethane CH3s 4.33 4.43 4.42 2.94 4.31 4.34 4.40 n-pentane CH3t,70.880.880.860.870.890.90CH2m 1.27 1.27 1.27 1.23 1.29 1.292-propanol CH3d,6 1.22 1.10 1.040.95 1.09 1.50 1.17 CH sep,6 4.04 3.90 3.78 3.67 3.87 3.92 4.02 pyridine CH(2)m8.628.588.588.538.578.538.52 CH(3)m7.297.357.39 6.667.337.447.45CH(4)m7.687.767.79 6.987.737.857.87 silicone grease i CH3s0.070.130.290.080.10 tetrahydrofuran CH2m 1.85 1.79 1.76 1.40 1.80 1.87 1.88 CH2O m 3.76 3.63 3.60 3.57 3.64 3.71 3.74 toluene CH3s 2.36 2.32 2.30 2.11 2.33 2.32CH(o/p)m7.177.1-7.27.187.027.1-7.37.16CH(m)m7.257.1-7.27.257.137.1-7.37.16 triethylamine CH3t,7 1.030.960.930.960.96 1.050.99 CH2q,7 2.53 2.45 2.43 2.40 2.45 2.58 2.57a In these solvents the intermolecular rate of exchange is slow enough that a peak due to HDO is usually also observed;it appears at2.81and3.30ppm in acetone and DMSO,respectively.In the former solvent,it is often seen as a1:1:1triplet,with2J H,D)1Hz. b2,6-Dimethyl-4-tert-butylphenol.c The signals from exchangeable protons were not always identified.d In some cases(see note a),the coupling interaction between the CH2and the OH protons may be observed(J)5Hz).e In CD3CN,the OH proton was seen as a multiplet atδ2.69,and extra coupling was also apparent on the methylene peak.f Long-chain,linear aliphatic hydrocarbons.Their solubility in DMSO was too low to give visible peaks.g Hexamethylphosphoramide.h In some cases(see notes a,d),the coupling interaction between the CH3and the OH protons may be observed(J)5.5Hz).i Poly(dimethylsiloxane).Its solubility in DMSO was too low to give visible peaks.Notes .Chem.,Vol.62,No.21,19977513.Chem.,Vol.62,No.21,1997NotesTable2.13C NMR Data aCDCl3(CD3)2CO(CD3)2SO C6D6CD3CN CD3OD D2O solvent signals77.16(0.0629.84(0.0139.52(0.06128.06(0.02 1.32(0.0249.00(0.01206.26(0.13118.26(0.02acetic acid CO175.99172.31171.93175.82173.21175.11177.21 CH320.8120.5120.9520.3720.7320.5621.03 acetone CO207.07205.87206.31204.43207.43209.67215.94 CH330.9230.6030.5630.1430.9130.6730.89 acetonitrile CN116.43117.60117.91116.02118.26118.06119.68 CH3 1.89 1.12 1.030.20 1.790.85 1.47 benzene CH128.37129.15128.30128.62129.32129.34tert-butyl alcohol C69.1568.1366.8868.1968.7469.4070.36 CH331.2530.7230.3830.4730.6830.9130.29 tert-butyl methyl ether OCH349.4549.3548.7049.1949.5249.6649.37 C72.8772.8172.0472.4073.1774.3275.62C C H326.9927.2426.7927.0927.2827.2226.60 BHT C(1)151.55152.51151.47152.05152.42152.85C(2)135.87138.19139.12136.08138.13139.09CH(3)125.55129.05127.97128.52129.61129.49C(4)128.27126.03124.85125.83126.38126.11CH3Ar21.2021.3120.9721.4021.2321.38C H3C30.3331.6131.2531.3431.5031.15C34.2535.0034.3334.3535.0535.36chloroform CH77.3679.1979.1677.7979.1779.44cyclohexane CH226.9427.5126.3327.2327.6327.961,2-dichloroethane CH243.5045.2545.0243.5945.5445.11 dichloromethane CH253.5254.9554.8453.4655.3254.78diethyl ether CH315.2015.7815.1215.4615.6315.4614.77 CH265.9166.1262.0565.9466.3266.8866.42 diglyme CH359.0158.7757.9858.6658.9059.0658.67 CH270.5171.0369.5470.8770.9971.3370.05CH271.9072.6371.2572.3572.6372.9271.63 1,2-dimethoxyethane CH359.0858.4558.0158.6858.8959.0658.67 CH271.8472.4717.0772.2172.4772.7271.49 dimethylacetamide CH321.5321.5121.2921.1621.7621.3221.09 CO171.07170.61169.54169.95171.31173.32174.57NCH335.2834.8937.3834.6735.1735.5035.03NCH338.1337.9234.4237.0338.2638.4338.76 dimethylformamide CH162.62162.79162.29162.13163.31164.73165.53 CH336.5036.1535.7335.2536.5736.8937.54CH331.4531.0330.7330.7231.3231.6132.03 dimethyl sulfoxide CH340.7641.2340.4540.0341.3140.4539.39 dioxane CH267.1467.6066.3667.1667.7268.1167.19 ethanol CH318.4118.8918.5118.7218.8018.4017.47 CH258.2857.7256.0757.8657.9658.2658.05 ethyl acetate C H3CO21.0420.8320.6820.5621.1620.8821.15 CO171.36170.96170.31170.44171.68172.89175.26CH260.4960.5659.7460.2160.9861.5062.32CH314.1914.5014.4014.1914.5414.4913.92 ethyl methyl ketone C H3CO29.4929.3029.2628.5629.6029.3929.49 CO209.56208.30208.72206.55209.88212.16218.43C H2CH336.8936.7535.8336.3637.0937.3437.27CH2C H37.868.037.617.918.148.097.87 ethylene glycol CH263.7964.2662.7664.3464.2264.3063.17“grease”CH229.7630.7329.2030.2130.8631.29n-hexane CH314.1414.3413.8814.3214.4314.45CH2(2)22.7023.2822.0523.0423.4023.68CH2(3)31.6432.3030.9531.9632.3632.73HMPA b CH336.8737.0436.4236.8837.1037.0036.46 methanol CH350.4149.7748.5949.9749.9049.8649.50c nitromethane CH362.5063.2163.2861.1663.6663.0863.22 n-pentane CH314.0814.2913.2814.2514.3714.39CH2(2)22.3822.9821.7022.7223.0823.38CH2(3)34.1634.8333.4834.4534.8935.302-propanol CH325.1425.6725.4325.1825.5525.2724.38 CH64.5063.8564.9264.2364.3064.7164.88 pyridine CH(2)149.90150.67149.58150.27150.76150.07149.18 CH(3)123.75124.57123.84123.58127.76125.53125.12CH(4)135.96136.56136.05135.28136.89138.35138.27 silicone grease CH3 1.04 1.40 1.38 2.10 tetrahydrofuran CH225.6226.1525.1425.7226.2726.4825.67 CH2O67.9768.0767.0367.8068.3368.8368.68 toluene CH321.4621.4620.9921.1021.5021.50C(i)137.89138.48137.35137.91138.90138.85CH(o)129.07129.76128.88129.33129.94129.91CH(m)128.26129.03128.18128.56129.23129.20CH(p)125.33126.12125.29125.68126.28126.29triethylamine CH311.6112.4911.7412.3512.3811.099.07 CH246.2547.0745.7446.7747.1046.9647.19a See footnotes for Table1.b2J PC)3Hz.c Reference material;see text.。
核磁碳谱溶剂峰
核磁碳谱溶剂峰
核磁碳谱溶剂峰是指在核磁共振碳谱图中，由于溶剂的存在而产生的一个信号峰。
溶剂峰通常出现在碳谱图的低场区域，由于溶剂中含有大量的碳原子，因此产生的峰比较宽，且峰形相对不规则。
溶剂峰可以用来作为参照峰，以确定其他峰的化学位移值。
常用的溶剂峰有甲醇（CH3OH）的峰位在50 ppm左右，二氯甲烷（CD2Cl2）的峰位在75 ppm左右，氘化双氯甲烷（CDCl3）的峰位在77 ppm左右等。
在进行核磁共振实验时，需要选择适当的溶剂并正确解析溶剂峰以获得准确的化学位移值。
- 1 -。
核磁共振中的溶剂分裂峰
核磁共振谱图本公司氘代试剂产品的核磁共振谱图氘代氯仿(CDCl3): H 谱| C 谱重水(D2O): H谱氘代二甲亚砜(DMSO-d6): H 谱| C 谱氘代丙酮(Acetone-d6): H 谱| C 谱氘代乙腈(CD3CN): H 谱| C谱氘代甲醇(CD3OD): H 谱| C 谱氘代三氟乙酸(CF3CO2D): H 谱| C 谱| F 谱氘代盐酸(DCl): H谱氘代硫酸(D2SO4): H 谱氘代氢氧化钠(NaOD): H谱四甲基硅(TMS)or ((CH3)4Si): H 谱| C 谱-----------------------------------------------------------------------------氘代氯仿 (CDCl3): H 谱氘代氯仿 (CDCl3): H 谱(含 TMS)氘代氯仿 (CDCl3): C 谱重水 (D2O): H 谱说明: 理论上 D2O 在氢谱不出峰, 呈现的是 0.1% 的 DOH 分子的氢峰氘代二甲亚砜 (DMSO-d6): H 谱说明: 氘代二甲亚砜的分子式为 CD3SOCD3, 理论上不出峰.呈现在氢谱的为其 0.2% 组分的 CHD2-SO-CD3.氢峰 a 呈现五重峰, 显示符合2ni+1 = 2(2)(1)+1 = 5 规律氘代二甲亚砜 (DMSO-d6): H 谱(含 TMS)说明: 氘代二甲亚砜添加 TMS 内标氘代二甲亚砜 (DMSO-d6): C 谱说明: 氘代二甲亚砜碳谱显示的是组分占 99.8% 的 CD3SOCD3(占 0.2% 的 CHD2-CO-CD3浓度低不显示)碳峰 a 呈现七重峰, 显示符合2ni+1 = 2(3)(1)+1 = 7 规律氘代丙酮 (Acetone-d6): H 谱说明: 氘代丙酮的分子式为 CD3COCD3, 但呈现在氢谱的为其 0.2% 组分的 CHD2-CO-CD3氢峰 a 呈现五重峰, 显示符合2ni+1 = 2(2)(1)+1 = 5 规律氘代丙酮 (Acetone-d6): C 谱说明: 氘代丙酮碳谱显示的是组分占 99.8% 的 CD3COCD3(占 0.2% 的 CHD2-CO-CD3浓度低不显示)碳峰 a 呈现七重峰, 显示符合2ni+1 = 2(3)(1)+1 = 7 规律氘代乙腈 (CD3CN): H 谱说明: 氘代乙腈的分子式为 CD3CN, 但呈现在氢谱的为其 0.2% 组分的 CHD2-CN 氢峰 a 呈现五重峰, 显示符合2ni+1 = 2(2)(1)+1 = 5 规律说明: 氘代乙腈碳谱显示的是组分占 99.8% 的 CD3CN (占 0.2% 的 CHD2-CN 浓度低不显示)碳峰 2 呈现七重峰, 显示符合2ni+1 = 2(3)(1)+1 = 7 规律碳峰 1 特别高场, 由于环电流的屏蔽影响.说明: 氘代丙酮的分子式为 CD3OD, 但呈现在氢谱的为其 0.2% 组分的 CD3OH 氢峰 a 呈现五重峰, 显示符合2ni+1 = 2(2)(1)+1 = 5 规律氘代甲醇 (CD3OD): H 谱(含 TMS)氘代甲醇 (CD3OD): C 谱说明: 氘代ji碳谱显示的是组分占 99.8% 的 CD3OD (占 0.2% 的 CHD2OD 浓度低不显示)碳峰 a 呈现七重峰, 显示符合2ni+1 = 2(3)(1)+1 = 7 规律氘代氢氧化钠(NaOD): H 谱。