Benzyl mercaptan is an organosulfur compound with the formula C6H5CH2SH. It is a common laboratory alkylthiol and occurs in trace amounts naturally. Condensed tannins can undergo acid-catalyzed cleavage in the presence of the nucleophilic benzyl mercaptan. Benzyl mercaptan has been identified in boxwood (Buxus sempervirens L.) and is known to contribute to the smoky aroma of certain wines. It also occurs naturally in coffee. It is created by the reaction of benzyl chloride and sodium hydrosulfide.