Katritzky, Alan R. Mehta, Shamal He, Hai-Ying Cui, Xilin Preparation of 1,5-Disubstituted Pyrrolidin-2-ones 1,5-Disubstituted pyrrolidin-2-ones <b>18a</b>−<b>g</b>,<b> 19a</b>−<b>h, </b>and <b>20a</b>−<b>f</b> were synthesized in good to excellent yields via the nucleophilic substitution of 5-(benzotriazol-1-yl)-1-substituted-pyrrolidin-2-ones <b>9</b> with allylsilanes, organozinc reagents, and phosphorus compounds. Compounds <b>9</b> and 5-(benzotriazol-2-yl)-1-substituted-pyrrolidin-2-one isomers <b>10</b> are readily prepared in total 70−84% yields from 2,5-dimethoxy-2,5-dihydrofuran (<b>7</b>), primary amines <b>8, </b>and benzotriazole; <b>9</b> and <b>10</b> react identically with nucleophiles. allylsilane;nucleophilic substitution;benzotriazole;benzotriazol;amines;Pyrrolidin;Compounds 9;dimethoxy;isomers;pyrrolidin;Disubstituted;Preparation;nucleophile;yield;phosphorus compounds;organozinc reagents 2000-06-17
    https://acs.figshare.com/articles/journal_contribution/Preparation_of_1_5-Disubstituted_Pyrrolidin-2-ones/3685095
10.1021/jo000219w.s001