Temperature Tunable Synthesis of Tetrahydro‑4H‑pyrrolo[3,2‑c]quinolin-4-ones and Dihydro‑1H‑benzo[b]azepines from 2‑Aminobenzonitriles and Donor–Acceptor Cyclopropanes

Tetrahydro-4H-pyrrolo[3,2-c]quinolin-4-ones and dihydro-1H-benzo[b]azepines are efficiently synthesized from 2-aminobenzonitriles and donor–acceptor cyclopropanes mediated by SnCl4 in moderate to good yields. The reaction involves the initial ring opening of a cyclopropane ring due to activation by SnCl4 followed by nucleophilic attack by amine to give an adduct, which after unprecedented rearrangement at two different reaction temperatures provides two nitrogen heterocyclic compounds. This methodology can be used for the synthesis of hexahydropyrrolo[3,2-c]quinolinone derivatives, the structure of which is found in biologically active molecules.四氢-4H-吡咯并[3,2-c]喹啉-4-酮与二氢-1H-苯并[b]氮杂䓬可由2-氨基苯甲腈与给体-受体环丙烷在四氯化锡（SnCl4）介导下高效合成，产物产率中等至优良。该反应首先经四氯化锡活化实现环丙烷开环，随后胺基发生亲核进攻得到加合物；该加合物在两种不同反应温度下经前所未有的重排反应，可得到两种含氮杂环化合物。本合成方法可用于制备六氢吡咯并[3,2-c]喹啉酮衍生物，这类化合物的结构存在于生物活性分子中。