The present invention provides methods for producing cannabinoids and cannabinoid analogs as well as a system for producing these compounds. The inventive method is directed to contacting a compound according to Formula I or Formula II with a cannabinoid synthase. Also described is a system for producing cannabinoids and cannabinoid analogs by contacting a THCA synthase with a cannabinoid precursor and modifying at least one property of the reaction mixture to influence the quantity formed of a first cannabinoid relative to the quantity formed of a second cannabinoid.