TY - JOUR A1 - Mollo, MarĂ­a C. A1 - Kilimciler, Natalia B. A1 - Bisceglia, Juan A. A1 - Orelli, Liliana R. T1 - Microwave-assisted synthesis of 2-substituted 4,5,6,7-tetrahydro-1,3-thiazepines from 4-aminobutanol JF - Beilstein Journal of Organic Chemistry PY - 2020/// VL - 16 SP - 32 EP - 38 SN - 1860-5397 DO - 10.3762/bjoc.16.5 PB - Beilstein-Institut JA - Beilstein J. Org. Chem. UR - https://doi.org/10.3762/bjoc.16.5 KW - cyclodehydration KW - medium-size heterocycles KW - microwaves KW - PPSE KW - tetrahydrothiazepines N2 - A general procedure for the synthesis of 2-substituted tetrahydro-1,3-thiazepines by MW-assisted cyclization of 4-thioamidobutanols is presented. The acyclic precursors were prepared in high overall yields by an expeditious three-step diacylation/thionation/deprotection sequence from 4-aminobutanol. Microwave-assisted ring closure of 4-thioamido alcohols promoted by trimethylsilyl polyphosphate (PPSE) in solvent-free conditions allowed for the synthesis of several hitherto unreported seven-membered iminothioethers bearing 2-aryl, alkenyl, aralkyl and alkyl substituents. The cyclodehydration reaction is likely to involve an SN2-type displacement and affords good to excellent yields of the desired heterocycles in very short reaction times. ER -