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Proton nuclear magnetic resonance

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1004: 1495:(around) to them. Carbon satellites are small because only very few of the molecules in the sample have that carbon as the rare NMR-active C isotope. As always for coupling due to a single spin-1/2 nucleus, the signal splitting for the H attached to the C is a doublet. The H attached to the more abundant C is not split, so it is a large singlet. The net result is a pair of evenly spaced small signals around the main one. If the H signal would already be split due to H–H coupling or other effects, each of the satellites would also reflect this coupling as well (as usual for complex splitting patterns due to dissimilar coupling partners). Other NMR-active nuclei can also cause these satellites, but carbon is most common culprit in the proton NMR spectra of organic compounds. 1446:
constant, then a triplet of doublets is seen. In the example below, the triplet coupling constant is larger than the doublet one. By convention the pattern created by the largest coupling constant is indicated first and the splitting patterns of smaller constants are named in turn. In the case below it would be erroneous to refer to the quartet of triplets as a triplet of quartets. The analysis of such multiplets (which can be much more complicated than the ones shown here) provides important clues to the structure of the molecule being studied.
1095: 1025: 1176:. The first proton will split the peak into two equal intensities and will go from one peak at 2.5 ppm to two peaks, one at 2.5 ppm + 3.5 Hz and the other at 2.5 ppm - 3.5 Hz—each having equal intensities. However these will be split again by the second proton. The frequencies will change accordingly: 1465:
If there are other NMR-active nuclei present in a molecule, spin-spin coupling will be observed between the hetero-atoms and the protons. This occurs most frequently in compounds that contain phosphorus or fluorine, as they are both spin 1/2 nuclei of 100% abundance. For example, the 1H signals for
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When a proton is coupled to two different protons, then the coupling constants are likely to be different, and instead of a triplet, a doublet of doublets will be seen. Similarly, if a proton is coupled to two other protons of one type, and a third of another type with a different, smaller coupling
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Even larger coupling constants may be seen in phosphines, especially if the proton is directly bonded to the phosphorus. Coupling constants for these protons are often as large as 200 Hz, for example in diethylphosphine, where the 1J P-H coupling constant is 190 Hz. These coupling constants are so
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The simple rules for the spin-spin splitting of NMR signals described above apply only if the chemical shifts of the coupling partners are substantially larger than the coupling constant between them. Otherwise there may be more peaks, and the intensities of the individual peaks will be distorted
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are split into a doublet by the fluorine atom; conversely the fluorine-19 NMR spectrum of this compound shows a quartet due to being split by the three protons. Typical 2J coupling constants between fluorine and protons are 48 Hz or so; the strength of coupling declines to 2 Hz in 4J coupling.
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peaks according to the (n + 1) rule of multiplicity. Below are NMR signals corresponding to several simple multiplets of this type. Note that the outer lines of the nonet (which are only 1/8 as high as those of the second peak) can barely be seen, giving a superficial resemblance to a septet.
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The integrated intensities of NMR signals are, ideally, proportional to the ratio of the nuclei within the molecule. Together with chemical shift and coupling constants, the integrated intensities allow structural assignments. For mixtures, the signal intensities can be used to determine molar
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In another molecule a proton resonates at 2.5 ppm and that proton would also be split into two by the proton at 1 ppm. Because the magnitude of interaction is the same the splitting would have the same coupling constant 7 Hz apart. The spectrum would have two signals, each being a
1079:, NMR spectra allow structural assignments by virtue of spin-spin coupling (and integrated intensities). Because nuclei themselves possess a small magnetic field, they influence each other, changing the energy and hence frequency of nearby nuclei as they resonate—this is known as 1589: 1106:
The effect of scalar coupling can be understood by examination of a proton which has a signal at 1 ppm. This proton is in a hypothetical molecule where three bonds away exists another proton (in a CH-CH group for instance), the neighbouring group (a
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The net result is not a signal consisting of 4 peaks but three: one signal at 7 Hz above 2.5 ppm, two signals occur at 2.5 ppm, and a final one at 7 Hz below 2.5 ppm. The ratio of height between them is 1:2:1. This is known as a
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to keep the resonance frequency constant. Additionally, the deuterium signal may be used to accurately define 0 ppm as the resonant frequency of the lock solvent and the difference between the lock solvent and 0 ppm (TMS) are well known.
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Baccolini, Graziano; Boga, Carla; Mazzacurati, Marzia; Sangirardi, Federico (2006-04-01). "High Atom-Economical One-Pot Synthesis of Secondary Phosphines and Their Borane Complexes Using Recycling Phosphorus Donor Reagent".
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Occasionally, small peaks can be seen shouldering the main H NMR peaks. These peaks are not the result of proton-proton coupling, but result from the coupling of H atoms to an adjoining
477:(HSQC) experiment, which correlates protons and carbons that are one bond away from each other. A hydrogen that is not attached to a carbon can be identified because it does not have a 208:
Deuterated solvents permit the use of deuterium frequency-field lock (also known as deuterium lock or field lock) to offset the effect of the natural drift of the NMR's magnetic field
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The coupling constant is independent of magnetic field strength because it is caused by the magnetic field of another nucleus, not the spectrometer magnet. Therefore, it is quoted in
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CH, as another example: the CH proton is attached to three identical methyl groups containing a total of 9 identical protons. The C-H signal in the spectrum would be split into
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peak will be split into a doublet by the CH peak—with one peak at 1 ppm + 3.5 Hz and one at 1 ppm - 3.5 Hz (total splitting or coupling constant is 7 Hz).
343:. Nuclei tend to be deshielded by groups which withdraw electron density. Deshielded nuclei resonate at higher δ values, whereas shielded nuclei resonate at lower δ values. 1007:
H NMR spectrum predicted for 1,4-dimethylbenzene. Under ideal conditions, the ratio of integrated signal of protons A and B is related to the structure of this molecule.
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large that they may span distances in excess of 1ppm (depending on the spectrometer), making them prone to overlapping with other proton signals in the molecule.
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ratios. These considerations are valid only when sufficient time is allowed for full relaxation of the affected signals, as determined by their T
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higher than 1 ppm and the other peak being the same number of hertz lower than 1 ppm. These peaks each have half the area of the former
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molecule, with all protons being chemically equivalent, giving one single signal, used to define a chemical shift = 0 ppm. It is
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Gottlieb HE; Kotlyar V; Nudelman A (October 1997). "NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities".
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values. A further complication arises from the difficulty of integrating signals of very different line shapes.
315:, are not precise, but typical - they are to be therefore regarded mainly as a reference. Deviations are in ±0.2 190: 139: 1759: 65: 1724: 1620: 1584: 1570: 1223:, keeping the chemical shift and coupling constants identical, the following changes are observed: 290: 1752: 1488: 319:
range, sometimes more. The exact value of chemical shift depends on molecular structure and the
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of a substance, in order to determine the structure of its molecules. In samples where natural
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The two doublets at 1 ppm and 2.5 ppm from the fictional molecule CH-CH are now changed into CH
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peak. The magnitude of this splitting (difference in frequency between peaks) is known as the
1102:(blue bar). The 1:1:1 triplet for HD arises from heteronuclear (different isotopes) coupling. 110:(deuterium = H, often symbolized as D) solvents especially for use in NMR are preferred, e.g. 336: 151: 416:
hybridized carbon atoms to an aliphatic chain. This causes a downfield shift of 1–2 ppm at C
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consists of a triplet at 1.5 ppm and a quartet at 3.5 ppm in a 3:2 ratio. The spectrum of
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Historically, deuterated solvents were supplied with a small amount (typically 0.1%) of
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Carbon satellites and spinning sidebands should not be confused with impurity peaks.
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protons may also be suppressed when a solvent containing acidic deuterium ions (e.g.
340: 332: 316: 182: 178: 1051:) group are not coupling with the other H atoms and appear as a singlet, but the -CH 1690: 1647: 167: 69: 1899: 1450: 1071:) are coupling with each other, resulting in a quartet and triplet respectively. 1523: 1439: 1131: 1108: 1076: 1036: 401: 359: 328: 308: 282: 267: 186: 76: 34: 1744: 1123:. A typical coupling constant value for aliphatic protons would be 7 Hz. 1888: 1798: 1659: 1467: 1088: 1032: 409: 297: 1702: 1667: 37:(in ppm on the horizontal axis). Signals from spectrum have been assigned 1719: 1111:) causes the signal at 1 ppm to split into two, with one peak being a few 300:, proton NMR is a powerful tool for molecular structure characterization. 19: 1602:
Balci, M., in "Basic H- and C-NMR Spectroscopy" (1st Edition, Elsevier),
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identical protons into components whose sizes are in the ratio of the
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3.5 Hz signal will be split into 2.5 ppm and 2.5 ppm - 7 Hz
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3.5 Hz signal will be split into 2.5 ppm + 7 Hz and 2.5 ppm
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Something split by three identical protons takes a shape known as a
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atoms in ethyl acetate regarding NMR. The hydrogens (H) on the CH
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for each proton reflects the abundance of the individual protons.
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Proton NMR spectra of most organic compounds are characterized by
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H NMR spectrum of a solution of HD (labeled with red bars) and H
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in which the spectrum is being recorded and other neighboring
205:). Deuterated solvents are now commonly supplied without TMS. 1407:+1 components, this type of splitting is said to follow the " 1127: 1112: 424: 369:. These cause a downfield shift of approximately 2–4 ppm for 1200:
and is an indicator that the proton is three-bonds from a CH
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Sometimes other peaks can be seen around H peaks, known as
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atom directly bonded to the substituent in question, and C
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of the atom to which the hydrogen atom is attached and to
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as they are small and appear around the main H peak i.e.
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Simple molecules have simple spectra. The spectrum of
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R. M. Silverstein, G. C. Bassler and T. C. Morrill,
1526:– letter designations for coupled spin-systems 1265:, each peak having relative intensities of 1:3:3:1. 1168:
In consequence the CH peak at 2.5 ppm will be split
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Nuclear magnetic resonance spectroscopy of proteins
346:Examples of electron withdrawing substituents are 254: 227: 1550:Spectrometric Identification of Organic Compounds 1886: 289:consists of a single peak at 7.2 ppm due to the 33:plotted as signal intensity (vertical axis) vs. 1774: 1157:peak will be twice that of the 2.5 ppm CH peak. 158:. However, a solvent without hydrogen, such as 1760: 1767: 1753: 1502:and are related to the rate of spin of an 1460: 1083:. The most important type in basic NMR is 106:protons must not be allowed to interfere. 1487:(C) atom. These small peaks are known as 377:and of less than 1–2 ppm for H atoms on C 1621:"Coupling of Protons with Fluorine Page" 1479:Carbon satellites and spinning sidebands 1093: 1023: 1002: 18: 1895:Nuclear magnetic resonance spectroscopy 1725:Spectral Database for Organic Compounds 1242:is coupled to two protons into a 1:2:1 335:. Hydrogen nuclei are sensitive to the 1887: 1039:. There are three different types of 1019: 475:heteronuclear single quantum coherence 1748: 1735:Extensive set of educational examples 998: 98:Simple NMR spectra are recorded in 41:atom groups (a through j) from the 13: 1415:neighbors appears as a cluster of 396:is an aliphatic C atom bonded to C 303: 270:in the range +14 to -4 ppm and by 16:NMR via protons, hydrogen-1 nuclei 14: 1911: 1713: 1227:The relative areas between the CH 189:of each analyte proton. TMS is a 50:Proton nuclear magnetic resonance 1741:1D Proton NMR] 1D NMR experiment 1449: 1438: 1035:plotted as signal intensity vs. 982: 979: 968: 965: 954: 951: 943: 725: 26:(1-dimensional) of a mixture of 423:Note that labile protons (-OH, 1674: 1630: 1613: 1596: 1577: 1559: 1542: 1207:This can be extended to any CH 1153:The total area of the 1 ppm CH 450:atom. This method is called a 1: 1720:H-NMR Interpretation Tutorial 1535: 140:deuterated dimethyl sulfoxide 91:H (hydrogen-1; i.e. having a 7: 1512: 10: 1916: 1215:-CH group is changed to CH 1172:by each proton from the CH 66:nuclear magnetic resonance 1786: 1583: 1422:With 2-methylpropane, (CH 1393:1 8 28 56 70 56 28 8 1 1130:(frequency) and not ppm ( 1457:(second-order effects). 1411:+1 rule": a proton with 949:=O (aliphatic aldehyde) 291:diamagnetic ring current 64:) is the application of 1461:Hetero-nuclear coupling 1382:1 7 21 35 35 21 7 1 963:=O (aromatic aldehyde) 1730:Proton Chemical Shifts 1103: 1072: 1029:Example H NMR spectrum 1008: 481:in the HSQC spectrum. 311:values, symbolized by 256: 229: 201:, 0.01% in 99.99% CDCl 46: 24:Example H NMR spectrum 1585:US patent 4110681 1235:subunits will be 3:2. 1097: 1027: 1006: 274:between protons. The 257: 255:{\displaystyle B_{0}} 230: 228:{\displaystyle B_{0}} 152:deuterated chloroform 22: 1371:1 6 15 20 15 6 1 977:M-H (metal hydride) 239: 212: 185:for referencing the 174:, may also be used. 160:carbon tetrachloride 45:shown at upper left. 1268:A peak is split by 1031:(1-dimensional) of 1020:Spin-spin couplings 1552:, 5th Ed., Wiley, 1500:spinning sidebands 1211:group. When the CH 1104: 1081:spin-spin coupling 1073: 1009: 341:electronic effects 272:spin-spin coupling 252: 225: 47: 1882: 1881: 1695:10.1021/jo971176v 1689:(21): 7512–7515. 1652:10.1021/ol060284d 1519:Mass spectrometry 1489:carbon satellites 1397: 1396: 1360:1 5 10 10 5 1 1278:Pascal's triangle 1121:coupling constant 1059:hydrogens of the 996: 995: 487:Functional group 333:functional groups 276:integration curve 183:internal standard 179:tetramethylsilane 1907: 1776:NMR spectroscopy 1769: 1762: 1755: 1746: 1745: 1707: 1706: 1678: 1672: 1671: 1646:(8): 1677–1680. 1634: 1628: 1627: 1625: 1617: 1611: 1600: 1594: 1593: 1592: 1588: 1581: 1575: 1574: 1569:. Archived from 1563: 1557: 1546: 1453: 1442: 1283: 1282: 999:Signal intensity 992: 988: 484: 261: 259: 258: 253: 251: 250: 234: 232: 231: 226: 224: 223: 168:carbon disulfide 112:deuterated water 95:for a nucleus). 72:with respect to 70:NMR spectroscopy 1915: 1914: 1910: 1909: 1908: 1906: 1905: 1904: 1885: 1884: 1883: 1878: 1782: 1773: 1716: 1711: 1710: 1679: 1675: 1640:Organic Letters 1635: 1631: 1623: 1619: 1618: 1614: 1601: 1597: 1590: 1582: 1578: 1567:"ChemicalShift" 1565: 1564: 1560: 1547: 1543: 1538: 1515: 1481: 1466:the protons in 1463: 1429: 1425: 1252: 1241: 1234: 1230: 1222: 1218: 1214: 1210: 1203: 1175: 1163: 1156: 1148: 1101: 1085:scalar coupling 1075:In addition to 1070: 1066: 1058: 1054: 1046: 1022: 1015: 1001: 990: 986: 907: 876: 859: 855: 838: 821: 790: 717: 700: 696: 665: 661: 560: 556: 510: 499: 493: 472: 455: 446:will replace a 439: 428: 419: 402:Carbonyl groups 399: 395: 384: 380: 376: 363: 306: 304:Chemical shifts 268:chemical shifts 246: 242: 240: 237: 236: 219: 215: 213: 210: 209: 204: 200: 187:chemical shifts 173: 165: 157: 149: 145: 137: 130:CO, deuterated 129: 125: 117: 17: 12: 11: 5: 1913: 1903: 1902: 1897: 1880: 1879: 1877: 1876: 1871: 1866: 1861: 1856: 1851: 1846: 1841: 1836: 1831: 1826: 1821: 1816: 1811: 1806: 1801: 1796: 1790: 1788: 1784: 1783: 1772: 1771: 1764: 1757: 1749: 1743: 1742: 1737: 1732: 1727: 1722: 1715: 1714:External links 1712: 1709: 1708: 1673: 1629: 1612: 1608:978-0444518118 1595: 1576: 1573:on 2016-03-06. 1558: 1540: 1539: 1537: 1534: 1533: 1532: 1527: 1524:Pople Notation 1521: 1514: 1511: 1480: 1477: 1462: 1459: 1427: 1423: 1395: 1394: 1391: 1388: 1384: 1383: 1380: 1377: 1373: 1372: 1369: 1366: 1362: 1361: 1358: 1355: 1351: 1350: 1349:1 4 6 4 1 1347: 1344: 1340: 1339: 1336: 1333: 1329: 1328: 1325: 1322: 1318: 1317: 1314: 1311: 1307: 1306: 1303: 1300: 1296: 1295: 1292: 1289: 1259: 1258: 1253:is coupled to 1250: 1247: 1239: 1236: 1232: 1228: 1220: 1216: 1212: 1208: 1201: 1193: 1192: 1185: 1173: 1166: 1165: 1161: 1158: 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1516: 1510: 1507: 1505: 1501: 1496: 1494: 1490: 1486: 1476: 1472: 1469: 1468:fluoromethane 1458: 1454: 1452: 1447: 1443: 1441: 1436: 1433: 1420: 1418: 1414: 1410: 1406: 1402: 1392: 1389: 1386: 1385: 1381: 1378: 1375: 1374: 1370: 1367: 1364: 1363: 1359: 1356: 1353: 1352: 1348: 1345: 1342: 1341: 1337: 1334: 1331: 1330: 1326: 1323: 1320: 1319: 1315: 1312: 1309: 1308: 1304: 1301: 1298: 1297: 1293: 1290: 1288: 1285: 1284: 1281: 1279: 1275: 1271: 1266: 1264: 1256: 1248: 1246:around 1 ppm. 1245: 1237: 1226: 1225: 1224: 1205: 1199: 1190: 1186: 1183: 1179: 1178: 1177: 1171: 1159: 1152: 1151: 1150: 1143: 1141: 1135: 1133: 1129: 1124: 1122: 1118: 1114: 1110: 1096: 1092: 1090: 1086: 1082: 1078: 1062: 1050: 1042: 1038: 1034: 1033:ethyl acetate 1030: 1026: 1017: 1005: 985: 976: 975: 971: 962: 961: 957: 948: 947: 940: 937: 934: 933: 929: 926: 923: 920: 919: 915: 912: 909: 903: 902: 898: 895: 892: 889: 888: 884: 881: 878: 872: 871: 867: 864: 861: 851: 850: 846: 843: 840: 834: 833: 829: 826: 823: 817: 816: 812: 809: 806: 803: 802: 798: 795: 792: 786: 785: 781: 778: 775: 772: 771: 767: 764: 761: 758: 757: 753: 750: 747: 744: 743: 739: 736: 733: 730: 729: 722: 719: 713: 712: 708: 705: 702: 692: 691: 687: 684: 681: 678: 677: 673: 670: 667: 657: 656: 652: 649: 646: 643: 642: 638: 635: 632: 629: 628: 624: 621: 618: 615: 614: 610: 607: 604: 601: 600: 596: 593: 590: 587: 586: 582: 579: 576: 573: 572: 568: 565: 562: 552: 551: 547: 544: 541: 538: 537: 533: 530: 527: 524: 523: 519: 516: 513: 506: 505: 501: 495: 489: 486: 485: 482: 480: 476: 469: 465: 461: 457: 449: 445: 441: 433: 429: 421: 415: 411: 407: 403: 391: 388: 372: 368: 364: 357: 353: 349: 344: 342: 338: 337:hybridization 334: 330: 326: 322: 318: 314: 310: 301: 299: 298:carbon-13 NMR 294: 292: 288: 284: 279: 277: 273: 269: 264: 247: 243: 220: 216: 206: 196: 192: 188: 184: 180: 175: 169: 161: 153: 141: 133: 121: 113: 109: 105: 101: 96: 94: 90: 86: 82: 78: 75: 71: 67: 63: 59: 55: 51: 44: 40: 36: 32: 29: 25: 21: 1793: 1686: 1683:J. Org. Chem 1682: 1676: 1643: 1639: 1632: 1615: 1598: 1579: 1571:the original 1561: 1553: 1549: 1544: 1508: 1497: 1482: 1473: 1464: 1455: 1448: 1444: 1437: 1431: 1421: 1416: 1412: 1408: 1404: 1400: 1399:Because the 1398: 1286: 1273: 1269: 1267: 1262: 1260: 1254: 1243: 1206: 1197: 1194: 1188: 1181: 1169: 1167: 1144: 1139: 1136: 1125: 1116: 1105: 1084: 1074: 1028: 1010: 467: 451: 422: 413: 345: 312: 307: 295: 280: 265: 207: 181:(TMS) as an 176: 97: 61: 57: 53: 49: 48: 23: 1403:th row has 1187:The 2.5 ppm 1180:The 2.5 ppm 1061:ethyl group 412:contribute 325:temperature 191:tetrahedral 79:within the 31:enantiomers 1889:Categories 1536:References 1419:+1 peaks. 1338:1 3 3 1 1276:th row of 373:atoms on C 108:Deuterated 74:hydrogen-1 54:proton NMR 1660:1523-7060 1493:satellite 1485:carbon-13 1055:- and -CH 479:crosspeak 444:deuterium 387:aliphatic 81:molecules 43:structure 1703:11671879 1668:16597139 1513:See also 1504:NMR tube 1346:quintet 1335:quartet 1327:1 2 1 1324:triplet 1313:doublet 1302:singlet 1257:protons. 464:methanol 406:olefinic 367:halogens 195:volatile 150:SO, and 132:methanol 100:solution 85:hydrogen 39:hydrogen 1787:Isotope 1780:isotope 1368:septet 1357:sextet 1263:quartet 1244:triplet 1204:group. 1198:triplet 1140:doublet 1117:singlet 1049:acetate 456:O shake 448:protium 321:solvent 287:benzene 120:acetone 104:solvent 89:isotope 28:menthol 1900:Proton 1701:  1666:  1658:  1606:  1591:  1390:nonet 1379:octet 1249:The CH 1238:The CH 1231:and CH 1160:The CH 1047:COO- ( 890:NHCOR 460:Acidic 385:is an 154:, CDCl 102:, and 93:proton 77:nuclei 1624:(PDF) 1255:three 1170:twice 1149:-CH: 1128:hertz 1113:hertz 773:COOR 759:COOH 714:OCOCF 679:OCOR 442:, as 352:-OCOR 162:, CCl 142:, (CD 122:, (CD 62:H NMR 60:, or 1699:PMID 1664:PMID 1656:ISSN 1604:ISBN 1554:1991 1316:1 1 1294:Row 1291:Name 1063:(-CH 958:9.5 941:3.1 938:2.6 935:SOR 930:3.1 927:2.5 924:2.1 916:4.4 913:4.2 910:4.1 899:3.7 896:3.3 893:2.9 885:3.6 882:3.1 879:3.0 868:3.6 865:3.0 862:2.6 847:2.8 844:2.4 841:2.2 830:3.0 827:2.7 824:2.5 813:3.0 810:2.5 807:2.1 799:2.4 796:2.1 793:2.0 787:CONR 782:2.5 779:2.3 776:2.0 768:2.6 765:2.3 762:2.1 754:2.6 751:2.2 748:2.1 745:COR 740:2.5 737:2.4 734:2.2 731:CHO 723:4.4 720:4.0 709:5.1 706:4.2 703:3.9 693:OCOC 688:5.0 685:4.1 682:3.6 674:4.3 671:4.0 668:3.8 653:3.7 650:3.4 647:3.3 639:3.8 636:3.5 633:3.3 625:4.2 622:3.2 619:2.2 611:4.1 608:3.4 605:2.7 597:4.0 594:3.4 591:3.0 583:4.8 580:4.4 577:4.3 569:2.9 566:2.6 563:2.3 548:2.8 545:2.2 542:1.7 539:C≡C 534:2.6 531:2.0 528:1.6 525:C=C 520:1.6 517:1.3 514:0.8 365:and 170:, CS 138:OD, 134:, CD 1778:by 1691:doi 1648:doi 1432:ten 1219:-CH 1134:). 991:−15 989:to 972:10 921:SR 852:NRC 804:CN 644:OR 630:OH 602:Br 588:Cl 502:CH 432:-SH 425:-NH 381:. C 360:-NO 356:-OR 348:-OH 317:ppm 166:or 114:, D 68:in 1891:: 1874:Pb 1869:Hg 1864:Pt 1859:Se 1854:Co 1849:Fe 1834:Si 1804:He 1697:. 1687:62 1685:. 1662:. 1654:. 1642:. 1305:1 1280:: 1189:- 1182:+ 1067:CH 987:−5 983:— 980:— 969:— 966:— 955:— 952:— 944:— 904:NO 873:NR 835:NR 818:NH 726:— 658:OC 616:I 574:F 511:R 507:CH 496:CH 490:CH 458:. 430:, 420:. 414:sp 404:, 400:. 358:, 354:, 350:, 327:, 323:, 293:. 56:, 1844:V 1839:P 1829:F 1824:O 1819:N 1814:C 1809:B 1799:H 1794:H 1768:e 1761:t 1754:v 1705:. 1693:: 1670:. 1650:: 1644:8 1626:. 1610:. 1556:. 1428:3 1426:) 1424:3 1417:n 1413:n 1409:n 1405:n 1401:n 1387:8 1376:7 1365:6 1354:5 1343:4 1332:3 1321:2 1310:1 1299:0 1287:n 1274:n 1270:n 1251:2 1240:3 1233:2 1229:3 1221:2 1217:3 1213:2 1209:n 1202:2 1174:2 1162:2 1155:2 1147:2 1100:2 1069:3 1065:2 1057:3 1053:2 1045:3 1041:H 1014:1 906:2 875:3 858:5 856:H 854:6 837:2 820:2 789:2 716:3 699:5 697:H 695:6 664:5 662:H 660:6 559:5 557:H 555:6 553:C 509:2 498:2 492:3 471:4 468:d 466:- 454:2 452:D 440:O 438:2 436:D 427:2 418:α 398:α 394:β 390:C 383:α 379:β 375:α 371:H 362:2 313:δ 248:0 244:B 221:0 217:B 203:3 199:3 172:2 164:4 156:3 148:2 146:) 144:3 136:3 128:2 126:) 124:3 116:2 52:(

Index


menthol
enantiomers
chemical shift
hydrogen
structure
nuclear magnetic resonance
NMR spectroscopy
hydrogen-1
nuclei
molecules
hydrogen
isotope
proton
solution
solvent
Deuterated
deuterated water
acetone
methanol
deuterated dimethyl sulfoxide
deuterated chloroform
carbon tetrachloride
carbon disulfide
tetramethylsilane
internal standard
chemical shifts
tetrahedral
volatile
chemical shifts

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