Yes, you can use the UPPER() function in the index statement:

INDEX ON UPPER(chemical) TAG chemical

Then, use something like:

SET ORDER TO chemical IN msds
IF SEEK(UPPER(var), 'msds')
  ...Sucess
ENDIF

>Actually I'm more concerned about searching for a string
>in a field. My table may have a record of msds.chemical='Acetone'.
>My user searches for ACETONE and never finds it in the index.
>Is it best to have UPPER() in the index?