- What is Reaxys?
Reaxys provides information about millions of chemical structures, reactions, and properties. It is an important tool for researchers who are synthesizing and characterizing chemical compounds, or searching for data on the physical, chemical, spectral, bioactivity, or toxicological properties of chemicals.
- What are the sources of Reaxys content?
Reaxys merges content from three important data sources:
- Beilstein Handbook
- The Beilstein Handbook up to 1959 (through Supplement IV) is the core source of historical content for organic compounds and reactions. Beilstein was a definitive source of information on the structures, reactions, and properties of organic carbon compounds, drawn from the journal literature back to the 18th century. (Due to licensing issues, the "Beilstein" name isn't used anywhere on the Reaxys site.)
- The Gmelin Handbook up to 1975 is the historical source of structures and properties of inorganic and metal-organic compounds, drawn from the journal and patent literature back to the early 19th century. After 1975, information was extracted from a small group of selected journals with varying degrees of thoroughness and timeliness. Gmelin's coverage of the literature was always uneven. See our Gmelin page for more details.
- Patent Chemistry Database
- A file of organic chemistry information drawn from selected English-language chemical patents (US, WO, EP, 1976- ). Additional historical patent coverage (1869-1980) comes from the Beilstein and Gmelin sources.
- What journals does Reaxys cover now?
- Until 2010 about 175 journals were indexed for Beilstein and about 60 for Gmelin, though update frequency varied considerably. After 2010 journal coverage grew towards 400 core chemistry titles for both segments combined. (The increase was not retrospective.) Coverage within a journal is highly selective. Data are only excerpted if they have a structure, experimental fact(s) and a credible citation.
In 2013 bibliographic data and abstracts for articles from over 16,000 additional publications were added into Reaxys for keyword and bibliographic searching under the Literature tab. However, chemical data have not been extracted from this additional content. Be aware that Reaxys is NOT a comprehensive index to the recent literature in the way that CAS' SciFinder is.
- What is the patent coverage in Reaxys?
- The Beilstein Handbook included selected worldwide organic chemical patents from about 1920 to 1980. Gmelin also covered chemical patents. The Patent Chemistry Database covers selected English-language chemical patents (US, WO, EP) since 1976, based on a subset of IPC codes. Prefer SciFinder (Chemical Abstracts) for more complete chemical patent coverage.
- What kinds of substances are not found in Reaxys?
In general, organic polymers, peptides, biological molecules, and mixtures are not included in Reaxys.
- How often is new data added?
- The database is updated biweekly. However, this doesn't necessarily mean that new articles are indexed within two weeks of publication.
- Why are PubChem records shown in Reaxys?
- Reaxys automatically searches PubChem in parallel when you do a substance structure/identification search. PubChem results are loaded under a separate tab and you can toggle back and forth between the two lists. If you enter additional Property search parameters, these are ignored in the PubChem search since the latter's data structure is very different. This can lead to confusing results, because you may get many PubChem hits but no Reaxys hits in a given search. Reaxys and PubChem are separate databases that are otherwise unrelated. Reaxys is literature-based; PubChem is crowd-sourced.
- Can I search by CAS Registry Numbers?
- Yes, but don't give up if it doesn't get a hit. Beilstein substance records created prior to 1994 ususally contain RNs as chemical identifiers. Some substance records added since 1994 do not. Not all Gmelin substance records contain CAS RNs.
A single substance record in Reaxys may contain several CAS RNs. This is because the two systems use different registration rules: CAS assigns RNs more narrowly than Beilstein or Gmelin did. CAS RNs should not be confused with Reaxys registry numbers, which are accession numbers within this database alone.
When searching CAS RNs you may have to normalize the CAS RN query by preceding it with zeros to give the first segment six or seven digits: 1234-56-7 could also be entered as 001234-56-7 or 0001234-56-7. If you don't find it the first way try the other ways too.
- Can I search by chemical names?
- Yes, but this is the least reliable kind of search. Reaxys indexes various synonyms for compounds, but don't rely solely on name string searching. CAS Registry Numbers, exact structures, and molecular formulas are better starting points. You can also generate a structure from a name, which you can then edit for further searching.
- Can I search by molecular formula?
- Yes, and there is a Formula Builder tool to help you create a proper query. This is especially useful for inorganic and organometallic/coordination compound searching. A similar Alloy tool lets you create MF searches specifying element percentages.
- Can I search by an old printed Beilstein or Gmelin reference?
- No, you must look up the compound instead. Some handbooks such as the Aldrich Catalog still provide Beilstein references (e.g. "Beil. 13, III, 2311"), but Reaxys does not include these at all. Some inorganic substance records in Reaxys do provide the corresponding Gmelin Handbook reference along with the source journal reference, but they are not searchable.
- What's the easiest way to find a property data value for a known compound?
- Select the "Names and Formulas" tab.
- Enter the CAS Registry Number in the appropriate box. (If the RN is in the Reaxys index you'll see it in the pull-down list as you type.) Click OK, then click Search on the next form. (If you don't have the CAS RN, or if you get no hits, do a search by structure, molecular formula, or chemical name.)
- In the table entry for the matching compound, click "Show Details" or the appropriate link under "Available Data".
- Open the desired data category to view the data table.
- Can I search by property values?
- Yes, but it can get complicated very quickly. Under the Names and Formulas tab, click on the Properties button and select property fields and enter values, which will then appear in search syntax form in the query box. Due to the huge number of property values in the Reaxys database, this technique is most useful in conjunction with a substructure search, and if you enter a range of values for a property it's best to keep that range narrow to avoid large results sets. You can also use the "exists" operator to limit to substances that contain a particular field without having to enter values for that field. Remember also that a compound record might contain many values for a given property, based on many different variables and conditions. To ensure that queried subfields are found in the same row of a data table, use the Proximity operator instead of the And operator. Example: BP.BP='69-72' PROXIMITY BP.P='760'
- Are property data in Reaxys critically evaluated?
- Some data excerpted from the old Handbooks were critically assessed for consistency, but more recent data are not. And since there's no way to tell the difference, you have to assume it's not. (Physical data drawn from patents should be viewed with particular skepticism.) All excerpted data are experimental, however - not derived or calculated.
- Does Reaxys contain spectra?
- Reaxys contains plentiful numerical spectral data on chemical compounds as reported in the primary literature, but not graphical spectra. You can use the form-based search to specify a type of spectroscopic data in various solvents.
- Does Reaxys link to full text of journals?
- Click the "Find It @ UT" button in the citation records to initiate a search for electronic full text. However:
- Many of the citations from Beilstein and Gmelin are quite old, and full text may not exist.
- If UT Austin does not have licensed access to the article, be sure to check our Catalog for our extensive archival print holdings.
- Can I save searches and set up alerts?
Yes. You need to create a personal registration in Reaxys first. Then you can change the application settings, save queries and search history, and set up alerts.
- Can I export references into EndNote?
Yes. When you open the Output tool, select "Literature Management Systems" for output format, and then import into EndNote or another bibliographic management software.
- Can I use it from off campus?
- Yes. Just connect via our proxied link and enter your UT EID and password when prompted. Access is restricted to current UT Austin students, faculty and staff.
- What structure editors are supported?
- Reaxys offers MarvinSketch and other internal editors that don't require plugins, but which require current Java and JRE. There are other Windows editors that require plugins: these can be downloaded from the Reaxys site. You can choose your favorite in the My Settings tab.
- I can't get the structure editor to open.
- This is most likely a Java problem. Make sure Java and cookies are enabled in your browser. Check your Java and/or JRE versions and update them if necessary. Try a different browser if necessary; sometimes launching IE will kick-start Java on Firefox, and on Macs sometimes Safari does a better job with applets. It varies from machine to machine. Consult the About Reaxys page for compatibility and version details.
- Should I search in SciFinder or Reaxys?
Both. SciFinder and Reaxys are complementary resources, and although both are ultimately based on the primary literature, they are quite different in the ways they scan and index the literature, the ways they register compounds and index reactions, and in the time periods they cover.
Reaxys is recommended for obtaining checked physico-chemical data and preparation/reaction methods for pure compounds, and especially for its near-comprehensive coverage of pre-1960 organic literature.
SciFinder excels with its wider coverage of literature and patents from ca. 1965 forward, its comprehensive registration of all types of chemical compounds, polymers, and mixtures, and its wider coverage of organic reactions after 1985. CAS also scans more source publications, indexes new material more rapidly, and is updated daily.
For chemists interested in synthesis, reactions and chemical properties, it is advisable to search both databases.
- Is there any reason to consult the printed Beilstein or Gmelin handbooks anymore?
- The Reaxys database is not a duplication of the Handbooks. Pertinent data and references were extracted from the printed works to create the retrospective portion of the electronic database.
The printed Beilstein Handbook entries, while in highly abbreviated German, provided some textual descriptions of synthetic chemistry that are not reflected in the online version. Beilstein Supplement V (Heterocyclics, 1960-79) has only been partially converted. Conversely, there is much information later added to the Beilstein database that was never included in the printed Handbook.
Numeric data from the print Gmelin Handbook up to 1975 is mostly in Reaxys. Handbook data from 1976 to 1998 (when it ceased) have not been added to the database. Print Gmelin remains useful because it was more textual and narrative in presentation and provided useful tables and graphs that are not duplicated in the database. It is a good idea to follow up a database search with a look in the corresponding Gmelin volumes.
Because the print and online formats are complementary, the printed Handbooks remain available in the Chemistry Library.
- What documentation is available?
- Some guides and videos are available at the Reaxys Training & Support site, but the coverage is not extensive. Useful academic guides with screenshots include NCSU and Michigan.
- Who pays for Reaxys?
- Reaxys at UT-Austin is cooperatively funded by the University Libraries, the Department of Chemistry, and the Division of Medicinal Chemistry in the College of Pharmacy.