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Both enantiomers of biologically and pharmaceutically interesting benzofuran-, benzothiophen-, and phenylfuran-based 1-heteroarylethanamines were prepared at close to theoretical yields by using Candida antarctica lipase B (Novozym 435) catalyzed (R)-selective N-acylation with isopropyl butanoate (enantiomeric ratio E > 200). The use of N-methyl-2-pyrrolidinone (NMP) as a cosolvent (1:30) in isopropyl butanoate solved the problem of low solubility of the compounds. Instability of the heterocyclic ring systems against traditional acid- and base-catalyzed hydrolysis was solved by using Candida antarctica lipase A as a commercial CAL-A-CLEA preparation for deprotection of the N-acylated (R) enantiomers in water. The slow, highly enantioselective (E > 200) hydrolyses of racemic butanamides was also observed in the presence of Novozym 435.