Reaxys is an extensive repository of experimentally validated data, including structures, reactions (including multi-step reactions) and physical properties. It also contains pharmacological, eco-toxicological and toxicological data, specific bioassay results, logPs, toxicity values, and other valuable data. Reaxys allows searching for substances by chemical name or by structure, as well as for single and multi-step reactions. Searches can also be performed for citations, which are indexed from the primary organic, inorganic and organometallic chemistry journal literature going back to 1772, as well as from the patent literature.
Reaxys is valuable for obtaining preparation/reaction methods and physico-chemical data for pure compounds, and especially for its thorough coverage of pre-1960 organic literature. Since its modern journal coverage is much more selective than SciFinder's, search results are usually more manageable.
Reaxys Education (open access web portal): https://ioct.tech/ReaxysEd/