News
January 2012 enhancements include:
- New Structure Editor: Elemental from Dotmatics has been added as a new structure editor. Further changes to the structure editor set-up now enable researchers who have not already set a preferred structure editor to choose directly in the structure query window between MarvinSketch (from ChemAxon), and Elemental. Elemental runs without Java, which can improve performance. Registered users can set their preferred structure editor via My Settings.
- Organometallic chemistry: The query type "coordinative bonds" available in some structure query editors (such as MarvinSketch) are now supported, enabling easier formulation of queries containing organometallic compounds. In addition, the structure representation for organometallic compounds has been improved - removing the display of valencies for greater readability.
- Synthesis Planner: Similarity searching is now applied within the synthesis planner. For compounds that do not have a published preparation method, or cannot be purchased, Reaxys will trigger a similarity search and possible alternative structures with known synthesis information will be displayed.
September 2011 enhancements:
- Structure similarity searching: a new similarity searching method allows you to quickly find results even if the structure of interest does not exist in Reaxys' dataset. Reaxys similarity searching provides results for five different similarities - the researcher can select which result set to view (positional/stereo isomers, near, medium, wide and widest similarity). These options can be re-accessed via a hyperlink below the results breadcrumb if the user wishes to further broaden or reduce the selected set of results.
- Reaction similarity searching: Reaxys will analyze the reaction query, identify the atoms and groups involved in the reaction process and run a search for all reactions that show similar characteristics.
- Structure Search Enhancements:
- Link nodes: it is now possible to use the Link nodes feature in the Structure Editors (Link nodes allow specifying query structures containing rings or chains of variable size).
- Unsaturated atom: an atom of a given structure query can be defined as being unsaturated
- Explicit hydrogens: Hydrogen atoms which are drawn explicitly in the structure query will no longer be ignored in substructure searches
- Lock atoms: atoms of a structure query can be locked, so that those positions remain unchanged in substructure queries
- Frequency exact in R-Groups: it is possible to define the exact frequency of R-groups in structure queries
- Multi-center bonds: Reaxys now supports queries containing multi-center bonds
- Aromatic bond: Reaxys supports the search for aromatic bond types.
What Is Reaxys?
Reaxys provides user-friendly access to reliable information about millions of chemical structures, reactions, and properties contained in the Beilstein and Gmelin databases. Reaxys is a key tool for researchers who are investigating synthetic methods of chemical compounds, characterizing synthesized compounds, or searching for data on physical, chemical, spectral, bioactivity, or toxicological properties.
Reaxys merges the content from three major data sources:
- Beilstein
- The definitive source of information on the structures, reactions, and properties of organic carbon compounds, drawn from the journal literature back to the 18th century. More about Beilstein
- Gmelin
- The definitive source of information on structures and properties of inorganic and metal-organic compounds, drawn from the journal and patent literature back to the early 19th century. More about Gmelin
- Patent Chemistry Database
- A file of organic chemistry information drawn from selected English-language chemical patents (US, WO, EP, 1976- ). Additional historical (1869-1980) patent coverage comes from the Beilstein and Gmelin files.
Frequently Asked Questions
>>> See also the
FAQ page on the Reaxys site.
- 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.
- Can I still use the old Crossfire Commander software?
- No, the Commander system was discontinued at the end of 2010.
- What structure editors are supported?
- Reaxys defaults to MarvinSketch, which requires current Java and JRE. Other Windows editors require plugins: ISIS Draw, Symyx Draw, and Crossfire Structure Editor. These can be downloaded from the Reaxys site.
- 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 Firefox, and on Macs sometimes Safari does a better job with applets than Firefox. It just varies from machine to machine. Consult the About Reaxys page for compatibility and version details.
- What compounds does Reaxys cover?
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The Beilstein and Gmelin file segments complement each other and cover different elements in the periodic table. The Beilstein file covers compounds of carbon with the elements shown in white:
Gmelin covers compounds without carbon; elemental and inorganic carbon, CO, CO2, carbonic acid, and carbides; pure elements, alloys, and compounds containing metallic elements shown in green, including inorganic, organometallic, and coordination compounds thereof; plus glasses, ceramics, minerals and some polymers.
In general, organic polymers, peptides, biological molecules, and mixtures are not included in Reaxys. For current counts of compounds and reactions included in Reaxys, click the About Reaxys link from any page.
- What are the sources of Reaxys' content?
- For the nitty-gritty details, click Help button in Reaxys, then choose Reaxys Content Details/Sources. A summary:
The Beilstein Handbook up to 1959 (Supplement IV) and the Gmelin Handbook up to 1975 are the core sources of historical content. Thereafter, information has been extracted from selected journals with varying degrees of thoroughness and timeliness. Gmelin's coverage of the literature was always uneven: some chemical elements were very extensively covered over time in multiple volumes and supplements, while others were never updated after the original volume was published. It is important to remember that Reaxys is not intended to be a comprehensive index to the recent literature in the way that CAS' SciFinder (Chemical Abstracts) is. Its coverage is much more selective.
- What journals does Reaxys cover?
- Until recently about 175 journals were covered for Beilstein and about 60 for Gmelin, though update frequency varied considerably. In 2010 Elsevier increased journal coverage towards 400 titles for both segments combined. (The increase is not retrospective.) Coverage within a journal is highly selective, however. Data are only excerpted if they have a structure, experimental fact(s) and a credible citation.
- 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 patents (US, WO, EP) since 1976, based on a subset of IPC codes. SciFinder (Chemical Abstracts) contains much more complete chemical patent coverage.
- 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 have CAS RNs. (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.)
A single compound 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. CAS RNs should not be confused with Reaxys registry numbers, which are accession numbers within this database alone.
- Can I search by chemical names?
- Yes, but this is the least reliable kind of search. Beilstein and Gmelin index various synonyms for compounds, but these are not comprehensive and you may miss the desired compound if you rely only on name string searching. CAS Registry Numbers, exact structures, and molecular formulas are better starting points.
- What's the easiest way to find a piece of property data for a known compound?
- Select the "Substances and Properties" tab.
- Select "Form-based search".
- Open the "Identification Data" menu.
- Enter the CAS RN 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 Search. If you don't have the CAS RN, or if you get no hits, do a search by structure, molecular formula, or - as a last resort - chemical name.
- Click View Results. 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's not very easy or intuitive. Under the Substances and Properties tab, click on the Properties (Advanced) tab and select property fields and enter values, which will then appear in search syntax form in the query box. The syntax is not very user friendly and the help pages aren't that helpful. Due to the enormous 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 massive 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 might contain many values for a given property field, based on many different variables and conditions.
- Are property data in Reaxys critically evaluated?
- Some data excerpted for 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?
- Beilstein and Gmelin contain lots of numerical spectral data on chemical compounds as reported in the 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?
- Reaxys provides links to full text in the citation records. However, two big caveats apply: 1) many of the citations from Beilstein and Gmelin are quite old, and full text may not exist; and 2) UT Austin does not have licensed access to all the possible content. In these cases, check our Catalog for print holdings.
- Can I export references into EndNote?
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Yes. When you open the Output tool, select "Literature Management Systems" for output format, and then import into EndNote or another bibliographic management software.
- Should I search in SciFinder or Reaxys?
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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. Literature references in Beilstein and Gmelin go back to the 18th century. Reaxys is updated monthly.
SciFinder excels with its more thorough coverage of literature and patents from 1967 forward, its comprehensive registration of all types of chemical compounds, polymers, and mixtures, and coverage of organic reactions after 1985. CAS also scans far more source journals than either Beilstein or Gmelin (over 9,000), indexes new material more rapidly, and is updated daily.
For chemists interested in synthesis, reactions and chemical properties, it is always advisable to search both databases. For a side-by-side comparison see the Database Comparison table.
- 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. It is not possible, for instance, to look up a printed Beilstein or Gmelin handbook reference in Reaxys.
The printed Beilstein Handbook entries, while in highly abbreviated German, may provide 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) has not been converted to the database format. Print Gmelin remains useful because it was more textual and narrative in presentation and provided useful tables and graphs that are not in the database. It is sometimes advisable 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.
- Where do the databases come from?
- The Beilstein database was originally created and maintained by the Beilstein Institute in Germany, drawing the core data from the printed Handbook. The original Gmelin Handbook was compiled by the Gmelin Institute (part of the Max Planck Institute) in Germany, and published by Springer Verlag. The Commander client interface was launched by MDL in the mid-1990s; Reed Elsevier acquired MDL in 1997. In March 2007 Elsevier purchased the Beilstein database outright from the Institute to merge with its MDL subsidiary. Later in 2007 Elsevier sold MDL to Symyx Technologies Inc., but retained ownership of the Beilstein content. The Gmelin content is owned by Gesellschaft Deutscher Chemiker (GDCh) and licensed to Elsevier.
- What documentation is available?
- Reaxys offers a robust array of support and instructional materials, including live webinars, training videos, downloads, and PDF and PowerPoint guides.
- Who pays for Reaxys?
- Reaxys at UT-Austin is cooperatively funded by the University Libraries, the Department of Chemistry & Biochemistry, and the Division of Medicinal Chemistry in the College of Pharmacy.
For more information about Reaxys, including questions about access, contact the Chemistry Library by email or phone 512-495-4600.
