One form of these compounds is produced by the disproportionation of aldehydes in the Tischenko reaction. A mild reducing agent used in (15[1])transfer hydrogenations of imines is named for Arthur Hantzch and this functional group. In the Yamaguchi (15[1])reaction, (15[1])TCBC forms an anhydride that is then catalyzed by DMAP to form this (-5[1])functional group. Polymers with this functional (15[1])group can be formed from DMT and ethylene glycol. The (10[1])(*) Dieckmann cyclization reacts one of these (10[1])compounds to produce (10[1])their “beta-keto” (10[1])type. Cyclic forms of these compounds are known as (10[2]-5[3])lactones. Refluxing a carboxylic acid with an (10[1])alcohol produces one of these (10[2])compounds in a reaction named for (10[2])Fischer. For 10 (10[1])points, name this functional (10[1])group with general formula (10[1])R-C-O-O-R-prime and a fruity aroma. (10[2]0[5])■END■