Advanced Structure Determination

    

• A final deduced chemical structure of the unknown compound 
•   1H NMR chemical shifts, integrations, splitting patterns and coupling constants written up
  following the ACS guidelines
   
•   13C NMR chemical shifts written up following the ACS guidelines  
   
•   Assignment of your 1H NMR signals to the protons in your deduced structure  
   
•   Assignment of your 13C signals to the carbons in your deduced structure
   

NMR Guidelines for ACS Journals

Updated December 2013

1. NMR Text (Experimental Section)
1.1 The compound must be clearly identified, for example in a header at the beginning

of a) the synthetic procedure or b) the summary of spectroscopic data.
1.2 List the nucleus being measured, any nucleus being broad-band decoupled, the

solvent used (formula preferred, e.g. C6D6 over benzene-d6), the standard used,
and the field strength.

1.2.1 Field strength should be noted for each spectrum, not as a comment in
the general experimental section.

1.2.2 The standard(s) may be specified in the general experimental section;
as an example, 1H NMR data recorded in C6D6 listed as “residual
internal C6D5H (δ 7.15)”.

1.2.3 Indicate solvent or peak suppression protocols used in collecting data.
1.3 List the probe temperature when it is accurately known; ambient probe

temperature is otherwise understood.
1.4 Give 1H NMR chemical shifts to two digits after the decimal point. Include the

number of protons represented by the signal, peak multiplicity, and coupling
constants as needed (J italicized, reported with up to one digit after the decimal).

1.4.1 The number of bonds through which the coupling is operative, xJ, may
be specified by the author if known with a high degree of certainty.

1.4.2 Accepted abbreviations for multiplicities and descriptors are:

s = singlet dd = doublet of doublets
d = doublet dt = doublet of triplets
t = triplet td = triplet of doublets
q = quartet br = broad signal
quint = quintet
m = multiplet (denotes complex pattern)

1.5 Chemical shifts should be listed consistently in a single article, starting either from

downfield to upfield or vice-versa. Please consult the Author Guidelines for
preferred formatting for each journal.

1.6 Assign peak identities under the following circumstances:
1.6.1 Non-decoupled or equivalent spectra have been collected (13C, 31P,

etc.).
1.6.1 2-D experiments have been performed.
1.6.2 Unambiguous assignment is possible without additional experiments,

such as in the case of an organometallic metal-hydride 1H signal, PF6 vs.
MPPh3

31P signal, etc.

1.7 Give 13C chemical shifts to one digit after the decimal point, unless an additional
digit will help distinguish overlapping peaks.

1.7.1 Include peak multiplicities for 1H-coupled 13C NMR spectra, or for
signals in 1H-decoupled spectra that are coupled to other magnetically
active nuclei.

1.7.2 A 13C NMR signal will be considered a singlet if the multiplicity is not
assigned.

1.7.3 Only rarely is a true multiplet observed in a 13C{1H} NMR spectrum.
However, a certain region may contain a group of unresolved peaks or
signals.

1.8 Mention of unobserved resonances is encouraged.

Example 1 (no 2-D data collected):

(η5-C5Me5Co)2-μ-(η

4:η4-C9H10) (1):
1H NMR (C6D6, 400 MHz): δ -0.53 (s, 1H), 0.72 (d, 1H, J =

4.0 Hz), 0.98 (s, 1H), 1.58 (s, 15H), 1.62 (s, 3H), 1.73 (s, 15H), 1.95 (d, 1H, J = 4.0 Hz), 5.62 (t,
1H, J = 4.0 Hz), 6.00 (t, 1H, J = 4.0 Hz). 13C{1H} NMR (C6D6, 125 MHz): δ 10.2, 10.6, 17.4, 38.3,
51.5, 54.2, 60.6, 80.8, 81.0, 88.0, 88.7.

Example 2 (2-D data collected):

Silvestrol (2): 1H NMR (CDCl3 with 0.05% v/v TMS, 400 MHz): δH 7.10 (2H, d, J = 8.9 Hz, H2′
and H6′), 7.03-7.07 (3H, m, H3′′, H4′′ and H5′′), 6.83-6.85 (2H, m, H2′′ and H6′′), 6.66 (2H, d, J
= 8.9 Hz, H3′ and H5′), 6.42 (1H, d, J = 1.8 Hz, H5), 6.26 (1H, d, J = 1.7 Hz, H7), 5.18 (1H, s,
H1′′′), 5.01 (1H, d, J = 6.6 Hz, H1), 4.52 (1H, s, H2′′′), 4.27 (1H, d, J = 14.2 Hz, H3), 4.15 (1H, br
d, J = 11.2 Hz, H4′′′), 4.05 (1H, t, J = 11.2 Hz, H3b′′′), 3.88 (1H, J = 14.3, 6.8 Hz, H2), 3.86 (3H,
s, OCH38), 3.69 (3H, s, OCH34′), 3.64 (3H, s, COOCH32), 3.49 (3H, br s, H5′′′ and H6′′′), 3.43-
3.47 (1H, overlapped, H3a′′′), 3.45 (3H, s, OCH32′′′).

13C NMR (CDCl3, 125 MHz): δC 170.6 (s,
COCH32), 160.6 (s, C4a), 160.0 (s, C6), 158.8 (s, C4′), 157.1 (s, C8), 136.7 (s, C1′′ ), 129.0 (d,
C2′ and C6′), 127.8 (d, C2′′, C3′′, C5′′ and C6′′), 126.6 (d, C4′′), 126.3 (s, C1′), 112.7 (d, C3′ and
C5′), 109.6 (s, C8a), 101.9 (s, C3a), 95.2 (d, C2′′′), 94.0 (d, C1′′′), 93.9 (d, C7), 93.4 (s, C8b),
92.9 (d, C5), 79.7 (d, C1), 70.7 (d, C5′′′), 68.3 (d, C4′′′), 63.3 (t, C6′′′), 59.0 (t, C3′′′), 55.9 (q,
OCH38), 55.1 (q, OCH34′), 55.0 (d, C3; q, OCH32′′′), 52.1 (q, COCH32), 50.3 (d, C2).

Note
Broad peaks between δH 1.5 to 3.0 ppm and at δH 3.79 ppm correspond to the protons of
the OH groups on C-1, C-8, C-5′′′ and C-6′′′, which disappeared after D2O exchange.

Example 3:

(E,E)-3,7,11-Trimethyl-2,6,10-dodecatrien-I-yl diphosphate (Farnesyl diphosphate, FPP, 3):
1H NMR (D2O, 300 MHz): δ 1.61 (s, 6H), 1.68 (s, 3H), 1.72 (s, 3H), 2.17-1.99 (m, 8H), 4.45 (d
of d, 2H, JH,H = 6 Hz, JP,H = 6 Hz), 5.23-5.15 (m, 2H), 5.46 (t, 1H, J = 6 Hz).

13C NMR (D2O, 75

MHz): δ 16.3, 16.6, 17.9, 25.9, 27.0, 27.2, 40.1, 40.2, 63.2, 120.5, 124.8, 125.1, 131.6, 135.9,
142.8. 31P NMR (D2O, 121.5 MHz): δ −6.56 (d, 1P, JP,P = 21.9 Hz), −9.89 (d, 1P, JP,P = 21.9 Hz).

2. NMR Spectra (Supporting Information)
Submission of spectra ( , x, .txt, , .tif) is strongly recommended for all new
and/or key compounds. When submitting spectra, please consider the following
guidelines:

2.1 A caption should be included on the spectrum, noting the nucleus being measured,

the solvent (formula preferred, e.g. C6D6 over benzene-d6) and the field strength.
2.2 A representation of the compound should be included on the spectrum – please

use ChemDraw or a related program. The compound identifier used in the
manuscript should be included.

2.3 The largest peak in the 1H NMR spectrum should normally arise from the
compound, not the solvent.

2.4 All peaks in the 1H NMR spectrum should be integrated. Chemical shift values
should be included.

2.5 The solvent peak should be clearly labeled on the spectrum.
2.6 All peaks should be visible on the spectrum. Insets are encouraged to show

expanded regions. At minimum, the spectral window should be -1 ppm to 9 ppm
for 1H NMR and -10 ppm to 180 ppm for 13C NMR.

2.7 Font should be clear and large enough to read (minimum of 10 point). Horizontal
orientation is preferred for spectra.

Example 1:

Example 2:

Example 3:

NMR Guidelines for ACS Journals