A talk I gave on August 19, 2012 at the 2012 ACS 244th national meeting held in Philadelphia, PA. This talk was given as a part of a series of 8 minutes long "lightening talks" on a variety of topics in chemistry and cheminfomatics. This talk looked at errors and missing information from literature in the field of chemistry.

1. Examining the Literature to
Demonstrate the Need for the
Careful Checking of
Reported Measurements
CINF Flash
ACS Symposia #244
Philadelphia, PA
Matthew McBride
Undergraduate Chemistry Major
Drexel University
Bradley Research Group
August 19, 2012

2. Main Points
1. Published results need to be compared
for consistency with the rest of
literature
2. Missing information in a published
article decreases the reliability of the
reported results

3. Preparing a Synthesis
Desire to synthesize:
(http://www.chemspider.com/4523376)
(1E,4E)-1,5-Di(2-naphthyl)-1,4-pentadien-3-
one
Aldol condensation between two molecules of
2-naphthaldehyde and one molecule of
acetone

4. Search the Literature
Using a database such as Reaxys©

5. Inconsistency
Conflicting reported melting points

6. Identify Compound
Always need to confirm that the listed melting
point corresponds to the desired compound
Always need to confirm that Reaxys© has
correctly listed the melting point
(doi: 10.1139/v90-351)

7. ONS Webservices
(http://onswebservices.wikispaces.com/meltingpoint)
Conclusion: The melting point value of
114°C is an outlier
[Andrew Lang]

8. Synthesis Procedure
How to make the compound
(doi: 10.1016/0040-4020(96)00788-0)
Reference to Organic Syntheses procedure
(http://www.orgsyn.org/orgsyn/orgsyn/prepcontent.asp?prep=cv2p0167)

9. Concentration
Claim that 1 mole of aldehyde can be
dissolved to make an approximately 0.5M
solution in 1:1 ethanol/water mixture
Picture: 0.16M solution
2-naphthaldehyde visible
Paper lacking details
(http://onschallenge.wikispaces.com/EXP337)

10. Drug Discovery
If interested in the compound as a potential
drug, check the bioactivity results

11. Cytotoxicity
Compound identified
Toxicity results listed against tumor cell lines
(doi:10.1016/j.bmc.2008.10.044)

12. Problem?
Check the characterization of the compound
(B46)
(doi:10.1016/j.bmc.2008.10.044)
There is none! No melting point, percent
yield, NMR..etc.
No scientific evidence to support the claim
that the listed compound was tested.
Reduces the reliability of the reported results

13. Characterization
HNMR spectrum should have a singlet (2H)
All peaks represent an even number of
hydrogen atoms

14. Characterization
Compare HNMR spectral data from literature
(US Patent 20100152493)
(doi: 10.1139/v90-351)
(doi: 10.1016/0040-4020(96)00788-0)
Need to check spectral data for consistency

15. Summary
Reported measurements, such as
melting points, listed in databases must
be considered in context with all
published values to identify outliers
Missing data and characterization
information reduces the impact and
reliability of published work