Editor's Page pubs.acs.org/Organometallics
An Editorial About Elemental Analysis
B
possible, while at the same time maintaining the high standards of excellence associated with Organometallics. Accordingly, Organometallics has decided to adopt the following position. The journal most strongly encourages characterization of all new compounds by elemental analysis. Where EA is collected and reported, the chemical yield must be reported for the specific batch for which EA is actually obtained. Organometallics will consider reports without EA on a case-bycase basis, with the ultimate decision on acceptability left to the editorial team, with input from the reviewers. Finally, in all cases, we now require that manuscripts describing synthetic work contain a statement explaining how the purity of the new compounds has been established. This statement may be included in the General Considerations part of the Experimental Section or provided for each new compound in the respective synthesis paragraph. Finally, there may be cases in which the bulk purity of a compound cannot be established. If this is the case, the author should clearly disclose and justify this shortcoming in the paper.
elieve it or not, questions surrounding elemental analyses (EA) in submitted manuscripts continue to occupy the forefront of exchanges among authors, reviewers, and editors at Organometallics. As an analytical method, EA gained pre-eminent importance in the 20th century, when techniques such as NMR, mass spectrometry, and X-ray crystallography were less routinely available, and when many university chemistry departments employed highly skilled technical staff for rigorous in-house analysis. In addition to providing information on the elemental composition of a compound, elemental analysis is one of the best available indicators of purity, especially for compounds that are not amenable to HPLC analysis. Indeed, elemental analysis is often described as the “gold standard” when it comes to assessing the bulk purity of a substance, a message that has been passed on to new generations of synthetic chemists over the years. Given the value of elemental analysis in providing information on bulk purity, many journals, including Organometallics, state in their Instructions to Authors that elemental analysis must be obtained for any new compound reported in a manuscript. This requirement is especially important when chemical yields are reported. While this guideline certainly contributes to the rigor and quality of the synthetic work we publish, its rigidity sometimes discourages authors from submitting exciting new findings. It also complicates consideration and acceptance of manuscripts that describe compounds not characterized by this technique. Worse yet is the possibility that this requirement can engender data fabrication, a practice often suspected, if ever proven. In less blatant but more widespread instances of misuse, EA is often obtained on a recrystallized sample, rather than on the isolated bulk substance for which the yield is reported, or may be reported for a single sample that gave acceptable values, when multiple others failed. These practices are likewise misleading, as they misrepresent the yields and purity of products obtained via the reported synthetic approach. We acknowledge, however, the real challenges that can exist. For synthetic organometallic chemistry, the high sensitivity of metal−carbon bonds often complicates elemental analysis, as few service laboratories are set up to handle (or accurately weigh) samples under an inert atmosphere. Sample decomposition is also commonplace when shipping sensitive substances under poorly controlled conditions, with elevated temperatures often being problematic, especially in the summer. Of course, technical solutions exist for these limitations, but their implementation can be costly. Given these practical and financial obstacles, many laboratories assess the purity of new compounds by NMR spectroscopy. NMR analysis on high-field instruments offers an efficient way to detect organic or organometallic impurities, with the caveat that NMR-silent impurities go unnoticed, and the method hence provides circumstantial rather than firm evidence about bulk purity and chemical yields. In light of all these points, we believe that it is time to reevaluate the journal’s position on this important technique. We envisage a system where elemental analysis is no longer an inflexible requirement, but rather very strongly encouraged. Our motivation is to capture the best organometallic chemistry © 2016 American Chemical Society
François P. Gabbaï*,† Paul J. Chirik‡ Deryn E. Fogg§ Karsten Meyer⊥ Daniel J. Mindiola∥ Laurel L. Schafer# Shu-Li You& †
■
Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, United States ‡ Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States § Center for Catalysis Research & Innovation and Department of Chemistry and Biological Sciences, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5 ⊥ Department of Chemistry and Pharmacy Inorganic Chemistry, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Egerlandstr. 1, 91058 Erlangen, Germany ∥ Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States # Department of Chemistry, The University of British Columbia, 2036 Main Mall, Vancouver, British Columbia, Canada V6T 1Z1 & State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, People’s Republic of China
AUTHOR INFORMATION
Corresponding Author
*E-mail for F.P.G.:
[email protected]. Published: September 23, 2016 3255
DOI: 10.1021/acs.organomet.6b00720 Organometallics 2016, 35, 3255−3256
Organometallics
Editor's Page
Notes
Views expressed in this editorial are those of the authors and not necessarily the views of the ACS.
3256
DOI: 10.1021/acs.organomet.6b00720 Organometallics 2016, 35, 3255−3256
