Task: Text Categorization
Input (English): This functionality can be used as a stereoselective directing group when using diiodomethane and zinc to form a cyclopropane ring from an alkene. Ketones are enantioselectively converted into a compound of this type using borane and a chiral ox-aza-boro-li-dine catalyst. Tartrates can be used to control stereochemistry when reacting allylic compounds of this type with tert-butyl hydroperoxide and a titanium catalyst to form epoxides with this functionality. An allylic compound of this type can be produced by reacting stoichiometric quantities of an alkene and an (*) aldehyde under high temperature, acidic conditions. These compounds are formed stereoselectively if hydrogen peroxide is used immediately after a hydroboration reaction. Under acidic conditions a carbonyl group can react with a molecule of this type to form a hemiacetal, and a molecule of this type can also react with an alkyl halide to make an ether. For 10 points, name this type of compound which can react with a carboxylic acid to form an ester.
Output (English): Science