Search or browse resources by class of compounds, molecular formula, systematic, common and trade names, synonyms, Registry numbers, SMILES, InchI codes and when available by structure.
Noted reactions can be found within the literature, but a best bet is to start with SciFinder-n property and reaction searches, followed by Reaxys for more in-depth and extensive coverage through the literature over time and PubChem for a medical/health sciences perspective.
List of Chemical Databases (Wiki) Not comprehensive, but a current listing of chemistry databases.
A long yet essential list of finding aids and specialty databases commonly used for finding reaction, spectra, property and unique data. A first start and an old favourite for common and most used chemicals is the CRC Handbook of Chemistry & Physics which is in print on reserve in the Library and older editions in the stacks.
Search using chemical or variant naming systems and structure when available limiting by spectra noting that predicated and experimental data may be incomplete, missing or not available for less than common compounds, small molecules and chemicals. Search Reaxys first by naming system and second by spectra and data, then search SciFinder by naming system for predicted values. Search both Reaxys and SciFinder to identify data linked to journal article papers and/or patents.