The Journal of Organic Chemistry, 49, p. 3435, 1984 DOI: 10.1021/jo00192a054
Synthesis, p. 223, 1980
1H-NMR
Expansion
table
Peak List Date: 23.07.2000 Time: 19:18 File Name: c: \ mydocu ~ 1 \ carvone \ picccarv \ 001001.1R Peak Results saved in File: - Peak Picking Parameter: Peak constant PC: 1.00 Noise: 32624 Sens. Level: 130495 Peak Picking region: Start (ppm) Start (Hz) End (ppm) End (Hz) MI (%) MAXI (%) 3999.5 643.0 8.00 1.29 2.53 100.00 Peak Picking results: Nr. Data Point Frequency PPM Intensity% Int. 1 27,086,716 8.7 6.6736 3337.67 14 963 2 14 968 11.3 3336.44 6.6711 35.30668 million 6.6687 37,279,372 14 973 3 11.9 3335.21 6.6657 34,489,456 4 14 979 11.0 3333.73 6.6623 33,366,342 14 986 5 10.7 3332.01 6 14 992 11.3 3330.53 6.6593 35.16274 million 7 14 997 11.0 3329.30 6.6569 34.35534 million 3327.82 15 003 8 26,249,558 8.4 6.6539 4.7102 62,156,552 9 18 953 19.9
13C-NMR (COM, DEPT)
DEPT
Carbon than the sum of protons, C10 H14 (134 formula weight), and 16 out of 150 molecular weight. δ199.4 carbonyl signal (C = O) is estimated to be, can be determined with the molecular formula C10H14O. Degree of unsaturation (C +1- H / 2) = 4 and is estimated to carbon double bond and two of four from 110.3 δ146.5, leaving one degree of unsaturation together with one carbonyl According to the ring can be estimated.
COSY
The one-dimensional 1H spectra in the side-swing write a letter to the peak of the NMR spectra, summarized in the table the correlation. Ground shaking in alphabetical HMQC spectra see the next section. If you do the same if drawn in order to analyze only the low-field COSY.
Here, they reveal the following partial structure.
- j (CH3) - c (CH) (estimated from the δ-allyl coupling we value and c J)
- i (CH3) - e '(CH2) (estimated from the δ-allyl coupling we value and c J). That i (CH3) - (C) = e '(CH2)
- Structure, including the first part, j (CH3) - (C) = c (CH) - h, h '(CH2) - g (CH) - f, f' (CH2)
Only from COSY and 1H-NMR, the structure of some compounds can be estimated. Identification is performed to obtain the data or preparation at the time of construction was estimated. Compounds are also present here can be estimated ccarvone would continue as a unknown compound below.
HMQC
- A low magnetic field side of the carbon, b, c. ... and shake the alphabet.
- Alphabetical shake directly linked to the proton. If the methylene protons of the inequality is correlated with higher magnetic field back out of two protons and one carbon "'" give.
This spectrum becomes incomplete decoupling c-axis across the carbon peak is completely decoupled j is not.
HMBC
Fill in the spectrum of the same alphabet shaken by HMQC.
Between protons and carbon through the binding of two or three there is a coupling of a few Hz (coupling distance, long-rangecoupling,, LRJCH ,2-3JCH). Similar peaks are not involved in measuring HMQC "turn phase" and "gradient pulse" so that off with a caution because it may appear Upon analysis of the spectrum . There may appear to be direct correlation between carbon and proton, which do not divide by 1JCH carbon decoupling (e, j, i). If you have a location just one proton, the observed correlation and unerring attention to this remote. Create a correlation table shown below, to be analyzed. Direct proton - carbon position in the Q, HMBC correlations will fill O. If you can not determine whether it has given not correlate with chemical shift is close to f and g of carbon length across the circle to fill in the table below it. Focus on the correlation structure connecting the estimated area so far. Carbon / proton = a / c, a / j, which leads to the planar structure by g / i. Also, b / i, a quaternary carbon by b d / j, which can be attributed the d.
Then fill all the HMBC correlations led to the structure, there is no place to check whether the correlation is not connected. Also, make a table similar to the above table, entering the number of protons and carbon within three bonds if it was this structure. To check for inconsistencies in comparison with the above table. Here is some correlation with the circle. HMBC measurements to set the delay time 1/2J. J values deviate significantly from having a carbon value - can hardly be the correlation between the protons. Coupling constant values refer to the remote data collection. Protons through the coupling of two or three - and even out the carbon is not always correlated. More than four out of the correlation, however, are accustomed to explain why such should be able to shape W.
NOESY, NOE difference spectra
A method to detect the spatial proximity between protons. Relative configuration, perform the attribution of methylene inequality. NOESY spectrum diagonal peak is negative (red), normally a positive NOE peak (black) was obtained at a peak negative exchange unwanted peak sometimes appear in the form of a COSY peak dispersion. Also used one-dimensional NOE difference spectra performed by irradiating a particular proton. Irradiation position is negative, becomes positive NOE, would like spectrum and cross section of the NOESY diagonal peak position and the irradiation position exactly.
When considering the stereochemistry molecular model formed a let.
E in the NOESY spectra, focusing on the methylene protons e ', e' is on the ring protons, e is this inequality can be attributed from the fact that the methylene gives NOE correlations of methyl protons of i. h, h ', f, the attribution of methylene inequality f' (or the same side or opposite protons g) the molecular model is used. axial substituents on carbon and g is less likely because, equatorial substituents, axial proton next g, and this time, close to the adjacent methylene protons g and those of cis protons and g, the trans What can be seen farther. is rotatable between an e gb free, while the e 'is on the ring proton h, h', g, f, and f ', and can approach the other methyl protons of i.
Since h was observed in NOE difference spectrum upon irradiation of g in NOE, and cis protons of g can be attributed with this.
f, for f 'is a clear NOE correlation has not been obtained, can be reserved for the J coupling between the proton. From molecular models, f, g and those of the cis methylene protons f ', g and small values of J closer to 90 ° dihedral angle g, and those of trans dihedral angles near 180 ° The higher the expected value of g and J since. The largest division of the division of the methylene protons splitting pattern of protons and these show that it is aware geminal coupling, shows that large values of g and J f '. As shown below, can be estimated from these relative stereochemistry. one proton geminal f is one reason that despite being split into pieces ddd one vicinal proton can be estimated from molecular models will be W-shaped coupling h and the proton.
In addition, the asymmetric carbon and carbon-g, this compound is present in two optical isomers, by NMR to determine the absolute configuration is not to be derivatized.
HETCOR
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