SDBS Integrated Spectral Database for Organic...
Transcript of SDBS Integrated Spectral Database for Organic...
SDBS Integrated Spectral Database for Organic Compounds
Sample Search for Chemistry 130
Grace Baysinger and Dr. Dave Keller
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SDBS – URL and Descriptionhttp://riodb01.ibase.aist.go.jp/sdbs/cgi-bin/cre_index.cgi?lang=eng
SDBS includes 6 different types of spectra under a directory of the compounds. The six spectra are:
Electron impact Mass spectrum (EI-MS), Fourier transform infrared spectrum (FT-IR)1H nuclear magnetic resonance (NMR) spectrum13C NMR spectrumLaser Raman spectrumElectron spin resonance (ESR) spectrum
It is possible to search by number of atoms, spectral peaks, plus compound name, molecular formula, molecular weight, and CAS Registry Number.
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SDBS Welcome Page
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SDBS - Search FormNote: for each peak, a
range of values is actually being searched
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Spectra Data Search Tips13C NMR
Search 13C spectral peaks first as they most closely match your lab data
1H NMRUse midpoints of multiplets as spectral peak valuesOH peaks for alcohols and acids, and NH peaks for amines may “wander” so your values may not agree with the database
IROnly include major peaks in IR search; usually < 2800 cm-1
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Spectra Data Search TipsBe sure to omit any peaks due to solvent
For Chem 130, the complete range for a spectral diagram is about:13C NMR: 0 to ~220 ppmIR: ~600 to ~4000 cm-1
1H NMR: 0 to ~12 ppm
Add no shift regions (i.e. no peak present) to refine a 13C or 1H NMR search
Review of General Search StrategySearch spectral peaks using conventions required by search interfaceSearch 13C NMR first, IR second, and 1H NMR lastRefine using no shift regions for 13C and 1H NMR dataFurther refine using heteroatom and/or hydrogen data
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SDBS - Tips for Converting Selected Lab Data to Search Strategies
Type of Search Lab Data Values SearchedError Range
Caveats
CAS Registry Number Not available from lab data 68-85-0 Use CAS RN to find/confirm physical properties
info and view spectral diagram.
Molecular Formula C6H5Br C6H5Br
Element symbols are case sensitive in many resources but not in SDBS. Put MF in Hill System Order (Carbon 1st, Hydrogen 2nd, and then all other elements in alphabetical order).
Number of Atoms5-6 Hydrogens, 1-4
Oxygens, No Nitrogen present
Hydrogen 5 to 6, Oxygen 1 to 4, Nitrogen 0 to 0
13C Peaks128, 129, 130, 133, 172 No Shift Region 165-140 and
125-5
128,129,130,133,172 No Shift Regions 165 140,125 5 +/- 2.0
Comma is the separator for multiple shifts. Range is defined by two numbers separated by a space. Ranges for multiple peaks – put space between upper and lower range of each peak, use comma between each range with no space between comma and values. Complete range for Chem 130 is 0 to ~220 ppm.
IR Peaks 1688, 1454, 1327, 1294, 936, 708 1688,1454,1327,1294,936,708 +/-10
Use either a space or a comma as the separator for multiple peaks. Use a hyphen to search a range of values (e.g. 700-750). Only include major peaks, usually < 2800 cm-1 Complete range for Chem 130 is ~700 to ~4000 cm-1
1H-NMR Peaks8.12, 7.6, 7.46 No Shift
Region 11-8.5 and 7-0.58.12,7.6,7.46 No Shift Region
11.0 8.5,7.0 0.5 +/- 0.2 ppm
Use midpoints of multiplets as spectral peak values. Comma is the separator for multiple shifts. Range is defined by two numbers separated by a space. Ranges for multiple peaks – put space between upper and lower range of each peak, use comma between each range with no space between comma and values. Complete range for Chem 130 is 0 to ~12 ppm.
revised 8 November 2009Don't use peaks from solvent!
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13C NMR Spectrum of Unknown
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SDBS 13C NMR Search –Peaks, No Shift Regions, and Number of Atoms
Use comma with no spaces for multiple peaks. For ranges use space between upper and
lower values. Use comma with no spaces for multiple
ranges. Peaks=128,129,130,172. No peak region=220 180,110 5
N, F, Cl, Br, I, S, P, Si not present
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SDBS - Brief Display of Results
Summary of available spectra (Yes/No)
Review molecular formulas and eliminate some compounds from further consideration based on
heteroatoms present. Remaining compounds can be quickly compared to unknown using 1H, 13C,and IR spectra as well as functional groups listed in name
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SDBS – View 13C NMR in CDCl3 for Benzoic Acid (=Unknown)
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IR Spectrum of Unknown
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SDBS IR Search –Peaks and Number of Atoms
Peaks = 1688,1454,1327,1
294,936,708
N, F, Cl, Br, I, S, P, Si not present
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IR Search ResultsResults on each page are sorted by
MW. Use heteroatoms and functional groups in chemical name of to help
eliminate candidates.
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SDBS - Viewing IR Spectra for Benzoic Acid
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1H NMR Spectrum of Unknown
For multiplets, use midpoints as
spectral peak values
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SDBS 1H NMR Search –Peaks, No Shift Regions, and Number of Atoms
Peaks = 8.12,7.6,7.46 No shift Regions = 11.0 8.5,7.0 0.5
N, F, Cl, Br, I, S, P, Si not present
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SDBS - 1H NMR Search Results
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SDBS – Viewing 1H NMR (90 MHz in CDCl3) for Benzoic Acid
Each hydrogen is labeled and
assigned to a peak with a given
chemical shift in ppm. Click on peak data button for list of individual peaks.
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SDBS – 1H NMR Peak Data for Benzoic Acid