The substance searching module in SciFinder is a great way to find reactions producing or implicating a particular substance. Once you have found the substance you are looking for in the CAS registry of substances, it is easy to find out more about it's chemical and physical properties, as well as connected literature, reactions, and syntheses.
If you are searching for substances with draw tool, you will see a "Structure Match" facet at the top of the filter pane on the left-hand side of the screen.
If you are looking to find information on reactions that produce a particular substance: